This document outlines the process for conducting a condition assessment of structures, which includes: (1) reviewing relevant documents, (2) performing a visual inspection and documenting any defects, (3) conducting field and laboratory testing, and (4) performing preliminary analysis and evaluation. The results are then used to determine if further investigation or repairs are required.
This document discusses various techniques for repairing and rehabilitating concrete structures. It covers topics such as concrete deterioration mechanisms, materials used for repair like cement mortars and polymers, and techniques like grouting, jacketing, and external bonding. Assessment of damaged structures involves preliminary investigation, detailed investigation using techniques like core cutting, rebar location, corrosion measurement, and pull-out tests to determine repair requirements. Underwater repair of structures also requires special considerations and techniques.
Shuttering in concrete construction is used as a mould for a structure in which fresh concrete is poured to harden subsequently curing
It is a part of formwork, or you may call it as derivative of formwork. Shuttering is a vertical temporary arrangement which is arranged to bring concrete in a desired shape.orFormwork which supports vertical arrangement is known as shuttering.
deterioration of concrete structures( repair and rehabilitation of structures)Korrapati Pratyusha
- Concrete is widely used in construction but is susceptible to defects from faulty design/materials, environmental effects like freezing/thawing, and chemical reactions.
- Common defects include cracking from plastic shrinkage during curing, drying shrinkage as concrete loses moisture over time, and damage from temperature changes causing expansion/contraction.
- Chemical reactions with acids, sulphates or aggregates can also deteriorate concrete through processes like carbonation, sulphate attack, or alkali-silica reaction. Preventive measures aim to minimize moisture movement and use durable materials.
Cracks in concrete and its remedial measures kamariya keyur
Cracks in concrete can be caused by various factors like plastic shrinkage, drying shrinkage, thermal variations, chemical reactions, errors in design and construction practices, structural overloads, foundation movement, and vegetation. The document classifies cracks as structural or non-structural and describes different types of cracks that can occur before or after concrete hardening. It provides details on the causes and prevention measures for different types of cracks like plastic shrinkage, drying shrinkage, crazing, thermal cracks, cracks due to chemical reactions, and those arising from poor construction practices. The summary focuses on the key information around classification, types, causes and remedies of cracks in concrete structures.
non destructive concrete testing equipment
non destructive concrete testing methods
non destructive test Penetration method
Rebound hammer method
Pull out test method
Ultrasonic pulse velocity method
Radioactive methods
methods of testing concrete
concrete strength testing methods
types of non destructive testing
non destructive concrete testing equipment
concrete tests pdf
destructive and non destructive testing
concrete testing procedures
non destructive test for concrete
destructive and non destructive testing
non destructive testing pdf
types of non destructive testing
non destructive testing methods
non destructive testing methods ppt
The document discusses repair and rehabilitation of concrete structures. It describes various causes of distress in concrete structures including structural causes, errors in design/construction, chemical reactions, and weathering. It then outlines the evaluation process for repair projects, including visual inspection, non-destructive testing, and laboratory testing to determine the extent of damage and appropriate repair methods. Specific causes of reinforcement corrosion like cracks, moisture, and concrete permeability are explained along with remedial measures.
this presentation deals with the different types of cracks generated in concrete during its usage and after its application and also methods to retrofit these cracks
Repair, rehabilitation and retrofitting of structures - RRSShanmugasundaram N
Strengthening of Structural elements, Repair of structures distressed due to corrosion, fire, Leakage, earthquake – DEMOLITION TECHNIQUES - Engineered demolition methods - Case studies.
This document discusses various techniques for repairing and rehabilitating concrete structures. It covers topics such as concrete deterioration mechanisms, materials used for repair like cement mortars and polymers, and techniques like grouting, jacketing, and external bonding. Assessment of damaged structures involves preliminary investigation, detailed investigation using techniques like core cutting, rebar location, corrosion measurement, and pull-out tests to determine repair requirements. Underwater repair of structures also requires special considerations and techniques.
Shuttering in concrete construction is used as a mould for a structure in which fresh concrete is poured to harden subsequently curing
It is a part of formwork, or you may call it as derivative of formwork. Shuttering is a vertical temporary arrangement which is arranged to bring concrete in a desired shape.orFormwork which supports vertical arrangement is known as shuttering.
deterioration of concrete structures( repair and rehabilitation of structures)Korrapati Pratyusha
- Concrete is widely used in construction but is susceptible to defects from faulty design/materials, environmental effects like freezing/thawing, and chemical reactions.
- Common defects include cracking from plastic shrinkage during curing, drying shrinkage as concrete loses moisture over time, and damage from temperature changes causing expansion/contraction.
- Chemical reactions with acids, sulphates or aggregates can also deteriorate concrete through processes like carbonation, sulphate attack, or alkali-silica reaction. Preventive measures aim to minimize moisture movement and use durable materials.
Cracks in concrete and its remedial measures kamariya keyur
Cracks in concrete can be caused by various factors like plastic shrinkage, drying shrinkage, thermal variations, chemical reactions, errors in design and construction practices, structural overloads, foundation movement, and vegetation. The document classifies cracks as structural or non-structural and describes different types of cracks that can occur before or after concrete hardening. It provides details on the causes and prevention measures for different types of cracks like plastic shrinkage, drying shrinkage, crazing, thermal cracks, cracks due to chemical reactions, and those arising from poor construction practices. The summary focuses on the key information around classification, types, causes and remedies of cracks in concrete structures.
non destructive concrete testing equipment
non destructive concrete testing methods
non destructive test Penetration method
Rebound hammer method
Pull out test method
Ultrasonic pulse velocity method
Radioactive methods
methods of testing concrete
concrete strength testing methods
types of non destructive testing
non destructive concrete testing equipment
concrete tests pdf
destructive and non destructive testing
concrete testing procedures
non destructive test for concrete
destructive and non destructive testing
non destructive testing pdf
types of non destructive testing
non destructive testing methods
non destructive testing methods ppt
The document discusses repair and rehabilitation of concrete structures. It describes various causes of distress in concrete structures including structural causes, errors in design/construction, chemical reactions, and weathering. It then outlines the evaluation process for repair projects, including visual inspection, non-destructive testing, and laboratory testing to determine the extent of damage and appropriate repair methods. Specific causes of reinforcement corrosion like cracks, moisture, and concrete permeability are explained along with remedial measures.
this presentation deals with the different types of cracks generated in concrete during its usage and after its application and also methods to retrofit these cracks
Repair, rehabilitation and retrofitting of structures - RRSShanmugasundaram N
Strengthening of Structural elements, Repair of structures distressed due to corrosion, fire, Leakage, earthquake – DEMOLITION TECHNIQUES - Engineered demolition methods - Case studies.
Rehabilitation and strengthening of existing structuresShahrukh Niaz
Rehabilitation and strengthening of existing structures involves repair techniques, underpinning, and addressing causes of damage. Repair restores structures to their previous condition while rehabilitation considers strength. Retrofitting modifies structures to increase resistance to seismic activity. Common repair techniques include crack injection, routing and sealing cracks, adding reinforcement, prestressing steel, and grouting. Underpinning strengthens foundations by extending them deeper or wider. Mass concrete and mini-pile underpinning are two types. Causes of damage to masonry buildings include heavy weight, low tensile strength, brittle behavior, and weak structural connections.
This document discusses different types of well foundations used in construction. It describes three main types: open caissons, which have open tops and bottoms; pneumatic caissons, which use air pressure; and box caissons, which are closed at the bottom. It provides details on each type, including advantages and disadvantages. Open caissons can be built to greater depths but inspection of the bottom is not possible. Pneumatic caissons allow work under water but require complex machinery. Box caissons have a lower construction cost but the foundation base cannot be inspected.
Deterioration of concrete structures can occur through various chemical, physical, and mechanical processes over time. Scaling and disintegration are forms of physical deterioration where the concrete's surface layers break down from freezing and thawing or weathering. Corrosion of reinforcement rebar can develop due to penetration of chloride ions or carbonation reducing the pH. Other causes include sulfate attack, alkali-aggregate reactions, abrasion, high temperatures, and erosion. Proper mix design and concrete quality can increase durability and prevent deterioration.
This document discusses various methods for repairing distressed concrete structures, including:
- Guniting, which involves pneumatically projecting cement and aggregates onto surfaces.
- Shortcreting, where mortar or concrete is projected onto surfaces to repair cracks or strengthen existing concrete.
- Crack repair techniques like stitching, routing and sealing, and resin injection.
- Shoring and underpinning methods to provide temporary or permanent support to unsafe or sinking structures, such as vertical, inclined, and pit shoring as well as underpinning foundations.
Properties of fresh and Hardened ConcreteVijay RAWAT
The document discusses various properties of fresh and hardened concrete. It describes workability, consistency, segregation, bleeding, mixing, placing, consolidating, and curing of fresh concrete. It also discusses compressive strength, tensile strength, modulus of elasticity, permeability, and durability of hardened concrete. The key properties of fresh concrete include workability, consistency, segregation, bleeding, setting time, and uniformity. Compressive strength is identified as the most important property of hardened concrete.
This document discusses quality control and durability factors in concrete. It defines quality as conformance to requirements and durability as a concrete's ability to resist deterioration when exposed to the environment. Several factors influence concrete durability, including the materials used, water-cement ratio, compaction, curing and the physical and chemical conditions of the service environment. Common durability issues include corrosion, cracking from sulfate attack or alkali-silica reaction, and carbonation reducing alkalinity. Proper quality control of materials and construction processes is needed to produce durable concrete.
This document discusses shoring and underpinning methods used to provide temporary or permanent support to structures. Shoring provides temporary stability during construction or repairs using techniques like raking, flying, or dead shores made of timber or steel. Underpinning supports existing foundations by strengthening soils using pit, pile, or chemical methods to allow additions without disturbing the structure. Proper design, installation, and precautions are needed for both techniques.
This document discusses concrete distress, its causes, and concrete repair systems. It defines distress as damage to concrete that can occur during production or service life due to varying conditions. Common causes of distress include structural loads, errors in design and construction, drying shrinkage, corrosion, and deterioration over time from chemical reactions, freezing/thawing, or weathering. Proper concrete repair requires determining the cause of damage, evaluating its extent, selecting repair methods, preparing the surface, applying repair materials, and curing. Durable repairs depend on high quality workmanship and materials to ensure the repair is well-bonded and resistant to future distress.
The document discusses cracks in buildings, including the types, causes, effects, and methods for repairing cracks. It identifies two main types of cracks: structural cracks that could endanger safety, and non-structural cracks caused by factors like moisture, temperature changes, or chemical reactions. Left unaddressed, cracks can accelerate concrete deterioration and carbonation, compromise waterproofing, and affect building appearance and durability. The document outlines various techniques for repairing cracks, such as epoxy injection, routing and sealing, stitching, drilling and plugging, and gravity filling. It emphasizes the importance of both preventing cracks and properly repairing existing cracks to maintain building integrity.
Formwork is used to create structures out of concrete that is poured into molds. It can be made from materials like steel, wood, aluminum, or prefabricated forms. Construction of formwork takes up 20-25% of total structure costs and involves supporting structures and molds. Proper formwork is designed to be easily removable, economical, leakproof, durable, rigid, provide smooth surfaces, be strong, and have adequate supports. Common types include conventional timber formwork, engineered prefabricated formwork, and modern systems like flying forms. Materials used include steel, plywood, plastic, and aluminum. Proper bracing and construction is needed to avoid failures from improper stripping, inadequate bracing, vibration
In this PPT, you will come to know about how cracks form on the structure and what preventive measures should follow to overcome cracks and different types of cracks
Reasons and solution to cracks in buildings.
<div dir="ltr"><br>Reasons and solution to cracks in buildings.<br><blockquote style="margin: 1.5em 0pt;"></blockquote></div>
Techniques for various structural repairUdayram Patil
Structural damage is crucial to safety. Proper remedial measures should always taken to avoid measure loss. This presentation provided various measure to repair structural damage.
This document discusses retrofitting of structures. Retrofitting is required when structures are damaged or do not meet current seismic standards. It summarizes various retrofitting techniques such as adding shear walls, infill walls, steel bracing, wall thickening, wing walls, mass reduction, base isolation, and jacketing structural elements. It provides examples of existing retrofitted structures in Gujarat. Retrofitting increases strength and ductility but can reduce space and increase foundation loads. Materials discussed include steel, fiber reinforced polymer, and reinforced concrete.
This document discusses column jacketing, which is a method of retrofitting and strengthening existing columns. It involves adding reinforced concrete, steel, or fiber-reinforced polymer around the column. The key steps are preparing the column surface, adding shear keys and reinforcement, applying a bonding agent, and casting the new concrete or installing the jacket. Column jacketing increases the strength and seismic capacity of the column. It improves confinement and increases axial, shear, and foundation load capacity without significant weight addition.
The document provides instructions for conducting pull-out tests to determine the compressive strength of concrete. It states that pull-out tests should be confirmed to BS 1881 Part 207 and give a direct tensile strength value. It describes how inserts can be cast into wet concrete or positioned in hardened concrete using an under-reamed groove. When testing, at least four pull-out tests should be performed at each location and a loading rate of 0.5 ± 0.2 kN/s should be used for 25mm diameter inserts. The compressive strength can then be calculated from the direct tensile strength value obtained during testing.
Design of Reinforced Concrete Structure (IS 456:2000)MachenLink
This is the 1st Lecture Series on Design Reinforced Cement Concrete (IS 456 -2000).
In this video, you will learn about the objective of structural designing and then basic properties of concrete and steel.
Concrete properties like...
1. Grade of Concrete
2. Modulus of Elasticity
3. Characteristic Strength
4. Tensile Strength
5. Creep and Shrinkage
6. Durability
Reinforced Steel Properties....
1. Grade and types of steel
2. Yield Strength of Mild Steel and HYSD Bars
The document discusses various types of cracks that can occur in buildings, their causes, and preventative measures. It describes cracks such as shrinkage cracks, hairline cracks, settlement cracks, vertical cracks, diagonal cracks, horizontal cracks, and structural cracks. Major causes of cracks outlined include initial shrinkage of materials, thermal movement, elastic deformation, creep movement, chemical reactions, foundation movement and soil settlement, cracking due to vegetation, permeability of concrete, structural design flaws, poor workmanship, lack of maintenance, and natural forces. The document provides detailed explanations of different crack types, patterns, and underlying causes.
This document discusses techniques for assessing the strength of concrete structures through visual inspection and destructive testing. It outlines the main steps in a condition assessment, which include planning a condition survey, performing a visual inspection, and conducting destructive testing such as taking concrete cores. The document then provides details on common defects that can occur in deteriorating concrete structures, such as scaling, disintegration, corrosion of reinforcement, and cracking. It also describes approaches for classifying the severity of defects observed in inspections.
Deterioration of concrete by Sharif Ullah Khan Wazirsharifullahkhan5
The document discusses various common defects that can cause the deterioration of concrete structures, including scaling, disintegration, erosion, corrosion, delamination, spalling, cracking, and chemical reactions like alkali-silica reaction. It provides details on the causes and symptoms of each defect. Placement issues like entrapped air, poor consolidation, and cold joints are discussed as well as service condition factors like chloride attack, freeze-thaw cycles, chemical exposure, and reinforcement corrosion.
Rehabilitation and strengthening of existing structuresShahrukh Niaz
Rehabilitation and strengthening of existing structures involves repair techniques, underpinning, and addressing causes of damage. Repair restores structures to their previous condition while rehabilitation considers strength. Retrofitting modifies structures to increase resistance to seismic activity. Common repair techniques include crack injection, routing and sealing cracks, adding reinforcement, prestressing steel, and grouting. Underpinning strengthens foundations by extending them deeper or wider. Mass concrete and mini-pile underpinning are two types. Causes of damage to masonry buildings include heavy weight, low tensile strength, brittle behavior, and weak structural connections.
This document discusses different types of well foundations used in construction. It describes three main types: open caissons, which have open tops and bottoms; pneumatic caissons, which use air pressure; and box caissons, which are closed at the bottom. It provides details on each type, including advantages and disadvantages. Open caissons can be built to greater depths but inspection of the bottom is not possible. Pneumatic caissons allow work under water but require complex machinery. Box caissons have a lower construction cost but the foundation base cannot be inspected.
Deterioration of concrete structures can occur through various chemical, physical, and mechanical processes over time. Scaling and disintegration are forms of physical deterioration where the concrete's surface layers break down from freezing and thawing or weathering. Corrosion of reinforcement rebar can develop due to penetration of chloride ions or carbonation reducing the pH. Other causes include sulfate attack, alkali-aggregate reactions, abrasion, high temperatures, and erosion. Proper mix design and concrete quality can increase durability and prevent deterioration.
This document discusses various methods for repairing distressed concrete structures, including:
- Guniting, which involves pneumatically projecting cement and aggregates onto surfaces.
- Shortcreting, where mortar or concrete is projected onto surfaces to repair cracks or strengthen existing concrete.
- Crack repair techniques like stitching, routing and sealing, and resin injection.
- Shoring and underpinning methods to provide temporary or permanent support to unsafe or sinking structures, such as vertical, inclined, and pit shoring as well as underpinning foundations.
Properties of fresh and Hardened ConcreteVijay RAWAT
The document discusses various properties of fresh and hardened concrete. It describes workability, consistency, segregation, bleeding, mixing, placing, consolidating, and curing of fresh concrete. It also discusses compressive strength, tensile strength, modulus of elasticity, permeability, and durability of hardened concrete. The key properties of fresh concrete include workability, consistency, segregation, bleeding, setting time, and uniformity. Compressive strength is identified as the most important property of hardened concrete.
This document discusses quality control and durability factors in concrete. It defines quality as conformance to requirements and durability as a concrete's ability to resist deterioration when exposed to the environment. Several factors influence concrete durability, including the materials used, water-cement ratio, compaction, curing and the physical and chemical conditions of the service environment. Common durability issues include corrosion, cracking from sulfate attack or alkali-silica reaction, and carbonation reducing alkalinity. Proper quality control of materials and construction processes is needed to produce durable concrete.
This document discusses shoring and underpinning methods used to provide temporary or permanent support to structures. Shoring provides temporary stability during construction or repairs using techniques like raking, flying, or dead shores made of timber or steel. Underpinning supports existing foundations by strengthening soils using pit, pile, or chemical methods to allow additions without disturbing the structure. Proper design, installation, and precautions are needed for both techniques.
This document discusses concrete distress, its causes, and concrete repair systems. It defines distress as damage to concrete that can occur during production or service life due to varying conditions. Common causes of distress include structural loads, errors in design and construction, drying shrinkage, corrosion, and deterioration over time from chemical reactions, freezing/thawing, or weathering. Proper concrete repair requires determining the cause of damage, evaluating its extent, selecting repair methods, preparing the surface, applying repair materials, and curing. Durable repairs depend on high quality workmanship and materials to ensure the repair is well-bonded and resistant to future distress.
The document discusses cracks in buildings, including the types, causes, effects, and methods for repairing cracks. It identifies two main types of cracks: structural cracks that could endanger safety, and non-structural cracks caused by factors like moisture, temperature changes, or chemical reactions. Left unaddressed, cracks can accelerate concrete deterioration and carbonation, compromise waterproofing, and affect building appearance and durability. The document outlines various techniques for repairing cracks, such as epoxy injection, routing and sealing, stitching, drilling and plugging, and gravity filling. It emphasizes the importance of both preventing cracks and properly repairing existing cracks to maintain building integrity.
Formwork is used to create structures out of concrete that is poured into molds. It can be made from materials like steel, wood, aluminum, or prefabricated forms. Construction of formwork takes up 20-25% of total structure costs and involves supporting structures and molds. Proper formwork is designed to be easily removable, economical, leakproof, durable, rigid, provide smooth surfaces, be strong, and have adequate supports. Common types include conventional timber formwork, engineered prefabricated formwork, and modern systems like flying forms. Materials used include steel, plywood, plastic, and aluminum. Proper bracing and construction is needed to avoid failures from improper stripping, inadequate bracing, vibration
In this PPT, you will come to know about how cracks form on the structure and what preventive measures should follow to overcome cracks and different types of cracks
Reasons and solution to cracks in buildings.
<div dir="ltr"><br>Reasons and solution to cracks in buildings.<br><blockquote style="margin: 1.5em 0pt;"></blockquote></div>
Techniques for various structural repairUdayram Patil
Structural damage is crucial to safety. Proper remedial measures should always taken to avoid measure loss. This presentation provided various measure to repair structural damage.
This document discusses retrofitting of structures. Retrofitting is required when structures are damaged or do not meet current seismic standards. It summarizes various retrofitting techniques such as adding shear walls, infill walls, steel bracing, wall thickening, wing walls, mass reduction, base isolation, and jacketing structural elements. It provides examples of existing retrofitted structures in Gujarat. Retrofitting increases strength and ductility but can reduce space and increase foundation loads. Materials discussed include steel, fiber reinforced polymer, and reinforced concrete.
This document discusses column jacketing, which is a method of retrofitting and strengthening existing columns. It involves adding reinforced concrete, steel, or fiber-reinforced polymer around the column. The key steps are preparing the column surface, adding shear keys and reinforcement, applying a bonding agent, and casting the new concrete or installing the jacket. Column jacketing increases the strength and seismic capacity of the column. It improves confinement and increases axial, shear, and foundation load capacity without significant weight addition.
The document provides instructions for conducting pull-out tests to determine the compressive strength of concrete. It states that pull-out tests should be confirmed to BS 1881 Part 207 and give a direct tensile strength value. It describes how inserts can be cast into wet concrete or positioned in hardened concrete using an under-reamed groove. When testing, at least four pull-out tests should be performed at each location and a loading rate of 0.5 ± 0.2 kN/s should be used for 25mm diameter inserts. The compressive strength can then be calculated from the direct tensile strength value obtained during testing.
Design of Reinforced Concrete Structure (IS 456:2000)MachenLink
This is the 1st Lecture Series on Design Reinforced Cement Concrete (IS 456 -2000).
In this video, you will learn about the objective of structural designing and then basic properties of concrete and steel.
Concrete properties like...
1. Grade of Concrete
2. Modulus of Elasticity
3. Characteristic Strength
4. Tensile Strength
5. Creep and Shrinkage
6. Durability
Reinforced Steel Properties....
1. Grade and types of steel
2. Yield Strength of Mild Steel and HYSD Bars
The document discusses various types of cracks that can occur in buildings, their causes, and preventative measures. It describes cracks such as shrinkage cracks, hairline cracks, settlement cracks, vertical cracks, diagonal cracks, horizontal cracks, and structural cracks. Major causes of cracks outlined include initial shrinkage of materials, thermal movement, elastic deformation, creep movement, chemical reactions, foundation movement and soil settlement, cracking due to vegetation, permeability of concrete, structural design flaws, poor workmanship, lack of maintenance, and natural forces. The document provides detailed explanations of different crack types, patterns, and underlying causes.
This document discusses techniques for assessing the strength of concrete structures through visual inspection and destructive testing. It outlines the main steps in a condition assessment, which include planning a condition survey, performing a visual inspection, and conducting destructive testing such as taking concrete cores. The document then provides details on common defects that can occur in deteriorating concrete structures, such as scaling, disintegration, corrosion of reinforcement, and cracking. It also describes approaches for classifying the severity of defects observed in inspections.
Deterioration of concrete by Sharif Ullah Khan Wazirsharifullahkhan5
The document discusses various common defects that can cause the deterioration of concrete structures, including scaling, disintegration, erosion, corrosion, delamination, spalling, cracking, and chemical reactions like alkali-silica reaction. It provides details on the causes and symptoms of each defect. Placement issues like entrapped air, poor consolidation, and cold joints are discussed as well as service condition factors like chloride attack, freeze-thaw cycles, chemical exposure, and reinforcement corrosion.
This document discusses various types of cracks that can occur in concrete structures. It begins by explaining that most cracks are caused by shrinkage as the concrete hardens. Cracks are then classified as either structural or non-structural. Non-structural cracks tend to be cosmetic while structural cracks can threaten safety. Several specific types of cracks are then described in detail, including those caused by sulfate attack, loading, plastic shrinkage, drying shrinkage, alkali-aggregate reaction, thermal effects, settlement, and corrosion of reinforcement steel. Factors that contribute to cracking and various prevention and repair measures are also outlined.
This document discusses various types and causes of cracks in buildings. It classifies cracks as either structural or non-structural and further categorizes them based on their width. Common causes of cracks include moisture movement, thermal variation, excessive loading, and foundation settlement. Plastic shrinkage, bleeding, delayed curing, and use of poor quality materials can lead to cracks in concrete before it hardens. Thermal expansion and contraction from temperature changes is another major cause of cracks. Various remedial measures are proposed to prevent or reduce cracking in structures.
The document discusses various types of damages that can occur in concrete structures such as aggregate expansion, corrosion of reinforcement bars, chemical damage from carbonation and chlorides, leaching, and structural defects from design or construction issues. It then describes methods to investigate existing structures including visual inspection, non-destructive tests like rebound hammer and ultrasonic pulse velocity tests, coring concrete samples, and half-cell potential testing. Maintenance and repair of damaged concrete structures is also discussed.
Lec#09&10.cracks,its terms,why concrete cracks.bzuShamsher Sadiq
This document discusses cracks in concrete, including definitions, terminology, and causes. It defines different types of cracks such as microcracks, hairline cracks, horizontal cracks, vertical cracks, and diagonal cracks. It describes characteristics of different crack patterns visible on concrete surfaces, such as crazing, block cracking, and freeze-thaw damage. Load-displacement behavior of beams is discussed, showing crack propagation with increasing loads. Causes of different crack orientations are outlined.
The document summarizes corrosion of steel reinforcement in concrete. It defines corrosion and describes the types as crevice and pitting corrosion. Chlorides are identified as the main cause as they can penetrate the protective oxide layer on the steel. Carbonation is also discussed as it lowers the pH and exposes the steel. The consequences of corrosion are outlined as rust formation which causes cracking, spalling and structural damage. Methods to prevent corrosion include coatings on the steel, using fly ash, galvanizing, and monitoring chlorides. Repair methods involve removing loose concrete, cleaning steel, applying protective coatings, and cement or epoxy patching.
The document discusses corrosion of steel reinforcement in concrete structures and methods to prevent corrosion. It defines corrosion as the deterioration of materials due to chemical reactions with the environment. Corrosion occurs due to carbonation or chloride attack, which reduces the alkalinity of the concrete and exposes the steel. Factors like low pH, high chloride content, lack of cover, and cracks in the concrete promote corrosion. Corrosion causes damage like rust staining, cracking, delamination and can ultimately lead to structural failure if left unchecked. The document recommends various preventive methods like using epoxy coated, galvanized or FRP rebars, proper compaction and curing of concrete, cathodic protection, and periodic maintenance to
Distress of concrete structures & their repair techniquesZaid Ansari
This document discusses concrete distress and repair techniques. It begins by explaining that concrete structures may need repair after 25-30 years of service without maintenance. It then lists common causes of concrete distress like weathering, environmental effects, poor design/construction, and water leakage leading to corrosion. The document outlines expected service lives for different structure types. It also describes common concrete failure modes and causes of early deterioration. The remainder of the document discusses techniques for identifying distressed concrete, various repair materials and methods, and the need for trained concrete workers.
Cracks on concrete.
How to catergorized cracks on newly poured concrete
Thermal cracks
Mass concrete
Fresh concrete
Cracks on concrete have many causes. They may affect appearance only, or it may indicate significant structural distress
This document summarizes common types of distress that can occur in concrete structures, including the causes and prevention methods. It identifies structural distress as caused by incorrect design, faulty construction, or overloading, which can endanger safety. Non-structural distress is caused by internally induced stresses and generally does not weaken structures. Common defects include cracking, spalling, disintegration, and porous or cracked concrete. Causes of deterioration include construction issues, drying shrinkage, temperature stresses, moisture absorption, reinforcement corrosion, chemicals, weathering, overloading, and external influences. Prevention focuses on proper design, construction practices, materials selection, and protective coatings.
1) Concrete structures can develop defects due to poor construction practices, poor quality control, and poor structural design and detailing.
2) Common defects include honeycombs caused by improper vibration and workability, cracks due to various stresses, and efflorescence caused by leaching of lime compounds.
3) Defects can be repaired through methods like using non-shrink grouts for honeycombs, grinding surfaces for minor formwork errors, and epoxy bonding, routing, resin injection, or grouting for cracks.
Concrete degradation and defects can occur due to a variety of reasons and have different effects. Common types of defects include honeycombing caused by ineffective vibration, concrete spalling due to corrosion of reinforcement bars, and cracking which frequently occurs on concrete surfaces from drying shrinkage or thermal contraction. These defects can be repaired but prevention is important, such as using adequate concrete cover and coatings on reinforcement bars to prevent corrosion. Left unaddressed, degradation and defects can negatively impact infrastructure through structural failures and collapse, putting lives at risk.
Concrete degradation and defects can occur due to a variety of reasons and have different effects. Common types of defects include honeycombing caused by ineffective vibration, concrete spalling due to corrosion of reinforcing steel from water and salt penetration, and cracking which frequently occurs on concrete surfaces from drying shrinkage, thermal contraction, or applied loads. These defects can be repaired but prevention is important, such as using adequate concrete cover and coatings on steel to prevent corrosion, and additives to improve workability and reduce cracking. Left unaddressed, degradation and defects can compromise the structural integrity of buildings and bridges, potentially resulting in collapse and loss of life.
This document discusses abrasion, erosion, and cavitation in concrete structures. It provides information on:
1) Abrasion is the wearing away of concrete surfaces through repeated rubbing, rolling, or sliding. Factors like water-cement ratio, aggregate grading, air content, curing, and finishing procedures affect abrasion resistance.
2) Erosion occurs when flowing water carrying solid particles damages concrete surfaces. Factors like particle size, velocity, and quality of concrete determine the degree of erosion. Erosion involves abrasive and cavitation actions.
3) Cavitation is the formation and collapse of air bubbles in water causing intense local stresses that damage concrete. Locations prone to cavitation
Infrastructure & Asset Inspection - Multitechnology approach concrete. by Marcel Poser.
A complete overview of the most comprehensive range of tools for concrete NDT inspection and asset management.
Common concrete problems include surface scaling, cracking, dusting, popouts, efflorescence, crazing, blistering, plastic shrinkage, and issues specific to stamped concrete. Most problems stem from errors in finishing, using low-quality materials, inadequate curing, and improper placement. While unavoidable in some cases, most concrete issues can be prevented or reduced through best practices in mixing, placing, finishing, and curing concrete.
This document discusses concrete, one of the most commonly used building materials. Concrete is a composite material made from readily available constituents like aggregates, sand, cement, and water. It is versatile and can be easily mixed to meet different needs. The document covers the properties of fresh concrete, including workability, consistency, segregation, bleeding, and setting time. It discusses factors that affect these properties and different tests used to measure consistency, such as slump tests. The document also covers mixing, placing, and consolidating concrete.
Additional deterioration of concrete structures( repair and rehabilitation of...Super Arc Consultant
The document provides an overview of common defects, deterioration mechanisms, and preventative measures for concrete structures. It discusses issues such as plastic shrinkage cracks during curing, drying shrinkage due to moisture loss, damage from freeze-thaw cycles, and chemical reactions like carbonation, sulfate attack, and alkali-aggregate reactions. Design errors, construction mistakes, environmental effects, and lack of maintenance are also highlighted as factors that can compromise concrete durability over time.
Presentation1 integrity problems of concrete piles-emergencySuper Arc Consultant
This document discusses integrity problems that can occur in concrete piles. It begins by outlining common defective construction practices for bored piles, such as boring problems, improper drilling procedures, inadequate base cleaning, improper reinforcement cage fabrication, and poor concreting techniques. The document then discusses how pile testing can be used to identify anomalies, flaws, and defects in piles. It provides examples of anomalies that are not flaws, anomalies that are flaws, flaws that are not defects, and anomalies that are defects. The goal of pile testing is to evaluate pile integrity and ensure piles are constructed properly.
This document provides an overview of soil risks and hazards for civil engineering projects. It discusses limitations of soil surveys and various hazards like expanding soils, gypsum, hydro-compactible soils, karst landscapes, landslides, liquefaction, and saturated soils. For expanding soils, it notes that proper foundations and drainage are needed to mitigate movement risks. For gypsum soils, it explains how excess gypsum can cause dissolution issues for utilities, foundations, and crops. The document also provides a case study analysis of soil samples and concludes by noting challenges with calcareous sand formations due to crushability and compressibility.
This presentation discusses various ground improvement techniques, including:
- Dynamic compaction and dynamic replacement, which use heavy weights or tampers to densify soils.
- Vibro compaction and vibro replacement, which use vibratory probes to densify or install stone columns in soils.
- Controlled modulus columns, jet grouting, and vertical drains which are reinforcement techniques that install cement, soil-cement, or aggregate columns or improve drainage in soils.
- Menard vacuum consolidation, which uses a vacuum and vertical drains to accelerate consolidation of soft soils.
The document provides examples of applications of these techniques and their advantages for improving bearing capacity and reducing settlement of soils.
The document provides an overview of various ground improvement techniques including dynamic compaction, vibro compaction, dynamic replacement, vibro replacement, controlled modulus columns, and stone columns. It discusses the concepts, procedures, advantages, limitations, and examples of each technique. Quality control and assurance for dynamic compaction techniques is also covered, emphasizing the importance of monitoring during field operations and post-treatment evaluation.
Geosynthetics in civil engineering (multifunctional uses of geosynthetics in ...Super Arc Consultant
This document discusses the use of geosynthetics in civil engineering. It begins with an introduction to geosynthetics, describing the different types including geotextiles, geogrids, geonets, geomembranes, geosynthetic clay liners, geopipes, geocomposites, and geocells. It then discusses the key functions of geosynthetics like separation, drainage, filtration, fluid barriers, reinforcement, and protection. The document provides examples of applications for geosynthetics in areas like pavements, retaining walls, drainage, erosion control, embankments, and reinforced foundations. It concludes by stating the benefits of geosynthetics like using local materials, employing un
Digital Twins Computer Networking Paper Presentation.pptxaryanpankaj78
A Digital Twin in computer networking is a virtual representation of a physical network, used to simulate, analyze, and optimize network performance and reliability. It leverages real-time data to enhance network management, predict issues, and improve decision-making processes.
Open Channel Flow: fluid flow with a free surfaceIndrajeet sahu
Open Channel Flow: This topic focuses on fluid flow with a free surface, such as in rivers, canals, and drainage ditches. Key concepts include the classification of flow types (steady vs. unsteady, uniform vs. non-uniform), hydraulic radius, flow resistance, Manning's equation, critical flow conditions, and energy and momentum principles. It also covers flow measurement techniques, gradually varied flow analysis, and the design of open channels. Understanding these principles is vital for effective water resource management and engineering applications.
Discover the latest insights on Data Driven Maintenance with our comprehensive webinar presentation. Learn about traditional maintenance challenges, the right approach to utilizing data, and the benefits of adopting a Data Driven Maintenance strategy. Explore real-world examples, industry best practices, and innovative solutions like FMECA and the D3M model. This presentation, led by expert Jules Oudmans, is essential for asset owners looking to optimize their maintenance processes and leverage digital technologies for improved efficiency and performance. Download now to stay ahead in the evolving maintenance landscape.
Applications of artificial Intelligence in Mechanical Engineering.pdfAtif Razi
Historically, mechanical engineering has relied heavily on human expertise and empirical methods to solve complex problems. With the introduction of computer-aided design (CAD) and finite element analysis (FEA), the field took its first steps towards digitization. These tools allowed engineers to simulate and analyze mechanical systems with greater accuracy and efficiency. However, the sheer volume of data generated by modern engineering systems and the increasing complexity of these systems have necessitated more advanced analytical tools, paving the way for AI.
AI offers the capability to process vast amounts of data, identify patterns, and make predictions with a level of speed and accuracy unattainable by traditional methods. This has profound implications for mechanical engineering, enabling more efficient design processes, predictive maintenance strategies, and optimized manufacturing operations. AI-driven tools can learn from historical data, adapt to new information, and continuously improve their performance, making them invaluable in tackling the multifaceted challenges of modern mechanical engineering.
Blood finder application project report (1).pdfKamal Acharya
Blood Finder is an emergency time app where a user can search for the blood banks as
well as the registered blood donors around Mumbai. This application also provide an
opportunity for the user of this application to become a registered donor for this user have
to enroll for the donor request from the application itself. If the admin wish to make user
a registered donor, with some of the formalities with the organization it can be done.
Specialization of this application is that the user will not have to register on sign-in for
searching the blood banks and blood donors it can be just done by installing the
application to the mobile.
The purpose of making this application is to save the user’s time for searching blood of
needed blood group during the time of the emergency.
This is an android application developed in Java and XML with the connectivity of
SQLite database. This application will provide most of basic functionality required for an
emergency time application. All the details of Blood banks and Blood donors are stored
in the database i.e. SQLite.
This application allowed the user to get all the information regarding blood banks and
blood donors such as Name, Number, Address, Blood Group, rather than searching it on
the different websites and wasting the precious time. This application is effective and
user friendly.
Mechatronics is a multidisciplinary field that refers to the skill sets needed in the contemporary, advanced automated manufacturing industry. At the intersection of mechanics, electronics, and computing, mechatronics specialists create simpler, smarter systems. Mechatronics is an essential foundation for the expected growth in automation and manufacturing.
Mechatronics deals with robotics, control systems, and electro-mechanical systems.
Supermarket Management System Project Report.pdfKamal Acharya
Supermarket management is a stand-alone J2EE using Eclipse Juno program.
This project contains all the necessary required information about maintaining
the supermarket billing system.
The core idea of this project to minimize the paper work and centralize the
data. Here all the communication is taken in secure manner. That is, in this
application the information will be stored in client itself. For further security the
data base is stored in the back-end oracle and so no intruders can access it.
8. CONDITION ASSESSMENT OF STRUCTURES
7
www.superarc.net
Deterioration of Concrete Structures
Why concrete structures fail?
❖ Concrete has long been known as a reliable
construction material, but deficiencies in material
selection, detailing, and design can affect the service
life of Concrete.
❖ Deterioration of concrete structures can become a
challenge for the owners of these structures. It is
important to identify these defects on time, and plan
appropriate repair strategies.
❑ Defect: An identifiable, unwanted condition that was not part of
the original intent of design.
❑ Deterioration: A Defect that has occurred over a period of time
9. CONDITION ASSESSMENT OF STRUCTURES
8
www.superarc.net
What Are the Different defects involved in the deterioration of concrete?
1- SCALING
What is it?
Scaling is referred to the loss of the surface portion of concrete
(or mortar) as a result of the freezing and thawing. It is a
physical action that usually leaves the aggregates clearly
exposed.
How it happens?
Scaling happens when the hydraulic pressure from water
freezing within concrete exceeds the tensile strength of
concrete. Scaling is more common in non-air-entrained
concrete, but can also occur in air-entrained concrete in the fully
saturated condition.
Severity (Ontario Structure Inspection Manual (OSIM)
Light - Loss of surface mortar to a depth of up to 5 mm without exposure of coarse aggregate;
Medium - Loss of surface mortar to a depth of 6 to 10 mm with exposure of some coarse aggregates;
Severe - Loss of surface mortar to a depth of 11 mm to 20 mm with aggregate particles standing out from the concrete
and a few completely lost.
Very Severe - Loss of surface mortar and aggregate particles to a depth greater than 20 mm.
10. 2- DISINTEGRATION
What is it?
Disintegration is the physical deterioration (such as scaling) or
breaking down of the concrete into small fragments or
particles.
How it happens?
It usually starts in the form of scaling. It may be also caused by
de-icing chemicals, sulphates, chlorides or by frost action.
CONDITION ASSESSMENT OF STRUCTURES
9
www.superarc.net
Severity (Ontario Structure Inspection Manual (OSIM)
Light - Loss of section up to 25 mm in depth with some loss of coarse aggregate;
Medium - Loss of section between 25 mm and 50 mm deep with considerable loss of coarse aggregate and exposure of
reinforcement;
Severe - Loss of section between 50 mm and 100 mm deep with substantial loss of coarse aggregate and exposure of
reinforcement over a large area.
Very Severe - Loss of section in excess of 100 mm deep and extending over a large area.
11. CONDITION ASSESSMENT OF STRUCTURES
10
www.superarc.net
3- EROSION
What is it?
Erosion is the deterioration of concrete surface as a result of
particles in moving water scrubbing the surface.
How it happens?
When concrete surface is exposed to the water-borne sand and
gravel, the surface gets deteriorated by particles scrubbing
against the surfaces. Flowing ice particles can also cause the
problem. It is an indicator of poor durability of concrete for that
specific exposure.
Severity (Ontario Structure Inspection Manual (OSIM)
Light - Loss of section up to 25 mm in depth with some loss of coarse aggregate;
Medium - Loss of section between 25 mm and 50 mm deep with considerable loss of coarse aggregate and exposure of
reinforcement;
Severe - Loss of section between 50 mm and 100 mm deep with substantial loss of coarse aggregate and exposure of
reinforcement over a large area.
Very Severe - Loss of section is in excess of 100 mm deep and extending over a large area.
12. 4- CORROSION OF REINFORCEMENT
What is it?
Corrosion is the deterioration of steel reinforcement in concrete.
Corrosion can be induced by chloride or carbonation. The corrosion can
result in cracking in the concrete cover, delamination in concrete decks,
etc.
How it happens?
When the concentration of chloride ions above the surface of
reinforcement reaches the threshold limit (which is the amount required
to break down the passive film) corrosion begins. The volume of
resulting material (rust) is 6-7 times, which increases the stress around
the rebar, and causes fracture and cracking. The cracks extend to the
surface of concrete over time; that is when we can visually see the sign
of rust over the surface of concrete.
CONDITION ASSESSMENT OF STRUCTURES
11
www.superarc.net
Severity (Ontario Structure Inspection Manual (OSIM)
Light - Light rust stain on the concrete surface;
Medium - Exposed reinforcement with uniform light rust. Loss of reinforcing steel
section less than 10%;
Severe - Exposed reinforcement with heavy rusting and localized pitting. Loss of
reinforcing steel section between 10% and 20%;
Very Severe - Exposed reinforcement with very heavy rusting and pitting. Loss of
reinforcing steel section over 20%.
13. CONDITION ASSESSMENT OF STRUCTURES
12
www.superarc.net
Light Stains on Concrete Surface Indicating Corrosion
of Reinforcement
15. CONDITION ASSESSMENT OF STRUCTURES
14
www.superarc.net
5- DELAMINATION
What is it?
“Delamination is defined as a discontinuity of the surface
concrete which is substantially separated but not completely
detached from concrete below or above it.” Delamination is
often identified by the hollow sound by tapping or chain
dragging of concrete surface.
How it happens?
The corrosion of reinforcement and subsequent cracking of the
cover can cause delamination. When the rebar have small
spacing, the cracking extends in the plane of the reinforcement
parallel to the exterior surface of the concrete.
Intercoat Delaminations
Severity (Ontario Structure Inspection Manual (OSIM)
Light - Delaminated area measuring less than 150 mm in any direction.
Medium - Delaminated area measuring 150 mm to 300 mm in any direction.
Severe - Delaminated area measuring 300 mm to 600 mm in any direction.
Very Severe - Delaminated area measuring more than 600 mm in any direction.
16. CONDITION ASSESSMENT OF STRUCTURES
15
www.superarc.net
6- SPALLING
What is it?
Spalling can be considered an extended delamination. In fact,
when the delamination continues, the concrete fragments
detach from a larger concrete mass.
How it happens?
If delamination is not repaired on time, the progress of damages
as a result of external loads, corrosion, and freezing and thawing
can break off the delaminated pieces.
Very Severe Spalling and
Delamination in
Concrete Beams
Severity (Ontario Structure Inspection Manual (OSIM)
Light - Spalled area measuring less than 150 mm in any direction or less than 25 mm in depth.
Medium - Spalled area measuring between 150 mm to 300 mm in any direction or between 25 mm and 50 mm in depth.
Severe - Spalled area measuring between 300 mm to 600 mm in any direction or between 50 mm and 100 mm in depth.
Very Severe - Spalled area measuring more than 600 mm in any direction or greater than 100 mm in depth.
17. CONDITION ASSESSMENT OF STRUCTURES
16
www.superarc.net
Very Severe Spalling in a Concrete
Pier Cap Due to Corrosion of
Reinforcement
Severe Local Spalling
18. 7- ALKALI-AGGREGATE REACTIONS
What is it?
It is the internal cracking of concrete mass as a result of a chemical
reaction between alkalis in the cement and silica in the aggregates.
The AAR/ASR (Alkali Silica reaction ) cracking are very famous for
their crack patterns.
How it happens?
The alkalis in the cement can react with the active silica in the
aggregates to form a swelling gel. When this gel absorbs water, it
expands, and applies pressure to surrounding environment which
makes the concrete crack.
CONDITION ASSESSMENT OF STRUCTURES
17
www.superarc.net
Severity
Light - Hairline pattern cracks, widely spaced, with no visible expansion of the concrete mass.
Medium - Narrow pattern cracks, closely spaced, with visible expansion of the concrete mass.
Severe - Medium to wide pattern cracks, closely spaced, with visible expansion and deterioration of concrete.
Very Severe - Wide pattern cracks, closely spaced, with extensive expansion and deterioration of concrete.
19. 8- CRACKING OF CONCRETE
What is it?
A crack is a linear fracture in concrete which extends partly or
completely through the member.
How it happens?
Some people believe that concrete is born with cracks; that its
ingredients, and how it is produced - from the batching plant
to pouring, setting, and curing - is influenced by so many
factors that cracking of concrete does not come as a big
surprise; and to a great extent, that might be true. Cracking of
concrete can happen in different stages: It can happen before
hardening of concrete, and it can happen in an old concrete
structure:
Before Hardening
+ Settlement within concrete mass
+ Plastic shrinkage
After Hardening
+ Drying shrinkage
+ Thermal contraction
+ Sub-grade settlement
CONDITION ASSESSMENT OF STRUCTURES
18
www.superarc.net
Severity
Hairline cracks - less than 0.1 mm wide.
Narrow cracks - 0.1 mm to 0.3 mm wide.
Medium cracks - 0.3 mm to 1.0 mm wide.
Wide cracks - greater than 1.0 mm wide.
20. CONDITION ASSESSMENT OF STRUCTURES
19
www.superarc.net
External Restraint Induced Cracks
(due to temperature increase in top surface
of beam)
24. CONDITION ASSESSMENT OF STRUCTURES
23
www.superarc.net
9-SURFACE DEFECTS
- Stratification;
- Segregation;
- Cold Joints;
- Deposits - efflorescence, exudation, incrustation, stalactite;
- Honeycombing;
- Pop-outs;
- Abrasion and Wear;
- Slippery Surface.
Surface defects are not necessarily serious in themselves; however, they are indicative of a potential weakness in
the concrete, and their presence should be noted but not classified as to severity, except for honeycombing and
pop-outs.
25. STRATIFICATION is the separation of the concrete components into horizontal layers in over-wetted or overvibrated
concrete. Water, laitance, mortar and coarse aggregates occupy successively lower positions. A layered
structure in concrete will also result from the placing of successive batches that differ in appearance.
SEGREGATION is the differential concentration of the components of mixed concrete resulting in non uniform
proportions in the mass. Segregation is caused by concrete falling from a height, with the coarse aggregates settling
to the bottom and the fines on top. Another form of segregation occurs where reinforcing bars prevent the uniform
flow of concrete between them.
COLD JOINTS are produced if there is a delay between the placement of successive pours of concrete, and if an
incomplete bond develops at the joint due to the partial setting of the concrete in the first pour.
DEPOSITS are often left behind where water percolates through the concrete and dissolves or leaches chemicals
from it and deposits them on the surface. Deposits may appear as the following:
CONDITION ASSESSMENT OF STRUCTURES
24
www.superarc.net
Efflorescence - a deposit of salts, usually white and powdery.
Exudation - a liquid or gel-like discharge through pores or cracks in the surface.
Incrustation - a hard crust or coating formed on the concrete surface.
Stalactite - a downward pointing formation hanging from the concrete surface, usually shaped like an icicle.
26. HONEYCOMBING is produced due to the improper or incomplete
vibration of the concrete which results in voids being left in the
concrete where the mortar failed to completely fill the spaces
between the coarse aggregate particles.
CONDITION ASSESSMENT OF STRUCTURES
25
www.superarc.net
Severity
Light - Honeycombing to a depth less than 25mm and 50mm.
Medium- Honeycombing to a depth between to a depth between
25mm and 50mm
Severe - Honeycombing to a depth between 50mm and 100mm.
Very Severe - Honeycombing to a depth greater than 100mm.
Efflorescence Incrustation
Stalactite
HONEYCOMBING Exudation
27. CONDITION ASSESSMENT OF STRUCTURES
www.superarc.net
Pop-outs Severity
Light - Pop-outs leaving holes up to 25 mm in depth.
Medium- Pop-outs leaving holes between 25 mm and 50 mm in depth.
Severe - Pop-outs leaving holes between 50 mm and 100 mm in depth.
Very Severe - Pop-outs leaving holes greater than 100 mm in depth.
POP-OUTS are shallow, typically conical depressions, resulting from the breaking away of small portions of the
concrete surface, due to the expansion of some aggregates or due to frost action. The shattered aggregate
particle may be found at the bottom of the depression, with a part of the aggregate still adhering to the pop-out
cone.
26
28. ABRASION is the deterioration of concrete brought about by vehicles or snow-plough blades scraping
against concrete surfaces, such as, decks, curbs, barrier walls or piers.
WEAR is usually the result of dynamic and/or frictional forces generated by vehicular traffic, coupled with
the abrasive influx of sand, dirt and debris. It can also result from the friction of ice or water-borne particles
against partly or completely submerged members. The surface of the concrete appears polished.
SLIPPERY CONCRETE SURFACES may result from the polishing of the concrete deck surface by the
action of repetitive vehicular traffic.
Severity
There are no severity descriptions given for slippery concrete surfaces as this is a serious and potentially
hazardous situation.
CONDITION ASSESSMENT OF STRUCTURES
www.superarc.net 27
34. 33
CONDITION ASSESSMENT OF STRUCTURES
➢ Condition assessment planning
Preliminary investigation: Detailed investigation:
YES
1. Review of relevant
documents
Visual inspection, with
documentation of defects
Field and laboratory testing
Preliminary analysis and
evaluation
1. Review of additional
documents and data source
Additional field
observations, and field and
laboratory testing
Detailed analysis and
evaluation
Is further
investigation
required?
2. 2.
3.
4. 3.
NO
Is
repairing
required?
Identify and analysis repair
options
YES
Final
report
Identify special conditions
to further considered (e.g.
maintenance, planning
NO
www.superarc.net
35. 34
CONDITION ASSESSMENT OF STRUCTURES
Review of plans and relevant documents
• To review documents from design
and construction process as well as
inspection and maintenance reports
is in general the easiest way of
gathering data about the structure to
be assessed.
It has to be assured that the reviewed
documents are correct.
Loads can be usually determined from
current loading codes and
environmental conditions may be
obtained from inspection reports.
• Resistance properties like material
and structural properties and
dimension can be obtained from:
– Construction specifications -
Codes
As-built drawings--architectural,
structural, mechanical, and
foundation plans
Construction documents (e.g.
material delivery documentation)
Documentation of performance,
defects, maintenance, and
changes (Alterations)
Reports of earlier inspection and
maintenance.
–
•
• –
–
–
34
www.superarc.net
37. CONDITION ASSESSMENT OF STRUCTURES
36
www.superarc.net
Scope of Visual Inspection
• Prior to the starting of visual inspection,
the structural engineer is to obtain a set
of the building’s structural layout plans
from the building owner.
• The availability of the structural layout
plan will help the structural engineer to:
a understand the structural system and
layout of the building;
b) identify critical areas for inspection;
c identify the allowable imposed loads,
in order to assess the usage and
possibility of overloading; and
d verify if unauthorised addition or
alteration works that affect the
structure of the building have been
carried out.
38. Visual Inspection Tools and Instruments
• Simple tools and Instruments like:
–
–
–
–
Camera
Magnifying glass
Binocular
Gauge for crack width
measurement
Chisel and hammer are usually
needed.
Pocket knife, screwdriver
Occasionally, a ladder or light
platform/scaffold tower can be
used for access to advantage.
–
–
–
CONDITION ASSESSMENT OF STRUCTURES
37
www.superarc.net
40. Scope of Visual Inspection
overloading or adverse effects on
deterioration or defects, the visual
the structural engineer otherwise
be taken
c any addition or alteration works
affecting the structure of the
building
• to identify any addition or alteration
works which can result in
the structure
If there are no signs of any structural
inspection should suffice and unless
advises, no further action needs to
CONDITION ASSESSMENT OF STRUCTURES
39
www.superarc.net
A visual inspection is generally carried
out of:
a the condition of the structure of
the building
• to identify the types of structural
defects
• to identify any signs of structural
distress and deformation
• to identify any signs of material
deterioration
b the loading on the structure of the
building
• to identify any deviation from
intended use, misuse and abuse
which can result in overloading
41. Visual inspection report (example)
1. General Information of the Building
• address, usage of the building,
maintenance history etc.
2. Structural System of the Building
• reinforced concrete, prestressed
concrete, steel, etc
3.
4.
Date and Scope of the Inspection
Survey of addition or alteration works
to building structure
Survey of signs of structural defects,
damages, distress, etc.
Survey of exposure to aggressive
environment
Conclusions on the structural
condition
Sketches, plans and photographs
5.
6.
7.
8.
CONDITION ASSESSMENT OF STRUCTURES
40
www.superarc.net
42. Examples of typical defects found by visual inspection
Erosion of Brick Face Efflorescence Brick Spalling/Delaminating
CONDITION ASSESSMENT OF STRUCTURES
41
www.superarc.net
Reference: ACI 201.1R-08 (Guide for Conducting a Visual Inspection of Concrete in Service
43. CONDITION ASSESSMENT OF STRUCTURES
42
www.superarc.net
Examples of typical defects found by visual inspection
Crack and Spall of
Concrete Around Steel
Member
Delaminating
Concrete
Over Reinforcement
Concrete Crack
45. CONDITION ASSESSMENT OF STRUCTURES
44
www.superarc.net
What is Detailed visual inspection?
A detailed visual inspection is Element-by-element “close-up” visual assessment of:
a) Material defects,
b) Performance deficiencies
c) Maintenance needs
Answer: a or b or c all of them
Who can perform it?
a) professional engineer
b) or a technician with structures inspection experience working under the direction of a
professional engineer.
Answer: a or b all of them
46. CONDITION ASSESSMENT OF STRUCTURES
45
www.superarc.net
Non-Destructive testing (NDT)
on
reinforced concrete structure
Concrete Testing
Testing
Concrete
Non-Destructive
Destructive
48. CONDITION ASSESSMENT OF STRUCTURES
47
www.superarc.net
Deliverables of NDT
Density
Elastic
Modulus
Cracks and Voids
Determination
Reinforcement
Location
strength
Surface
Hardness
Quality of
Workmanship
Surface
Absorption
49. CONDITION ASSESSMENT OF STRUCTURES
48
www.superarc.net
NDT Objectives
NDT methods are extremely valuable in
assessing the condition of structures,
such as bridges, buildings, elevated
service reservoirs and highways etc.
– Position and condition of steel
reinforcement
Concrete cover over the
reinforcement.
Reliable assessment of the
integrity or detection of defects of
concrete members even when they
are accessible only from a single
surface.
–
• The principal objectives of the NDT /
PDT of concrete in situ is to assess one
or more of the following properties:
–
–
–
–
–
–
–
–
In situ strength properties
Durability
Density
Moisture content
Elastic properties
Extent of visible cracks
Thickness of structural members
having only one face exposed
50. CONDITION ASSESSMENT OF STRUCTURES
49
www.superarc.net
NDT Advantages and Disadvantages
Disadvantages
Advantages
• More than one test method may be
required
Environmental conditions may
effect or distort results
Construction details & building
components may effect results
Some conditions cannot be
determined with a reasonable
degree of accuracy without
destructive testing
• Access to hidden items – “see
through walls”
Better investigations with NDT
Rapid accumulation of data
Generally less expensive than
destructive testing
Minimize interruption of building
services
Evaluation and quality assurance
•
•
•
• •
•
•
•
51. Typical situations where non-destructive testing is needed
representative of the quality to be
deterioration of concrete resulting from
external or internal chemical attack or
effects
concrete
change of use of a structure for
• Quality control of pre-cast units or
construction in situ
• Monitoring of strength development in
relation to load application or similar
purpose
• Location and determination of the
extent of cracks, voids, honeycombing
and similar defects within a concrete
structure
• Determining the concrete uniformity,
possibly preliminary to core cutting,
load testing or other more expensive or
disruptive tests
• Determining the position, quantity or
condition of reinforcement
• Increasing the confidence level of a
• Determining the extent of concrete
variability in order to help in the
selection of sample locations
assessed
• Confirming or locating suspected such
factors as overloading, fatigue,
change, fire, explosion, environmental
• Assessing the potential durability of the
• Providing information for any proposed
insurance or for change of ownership.
smaller number of destructive tests
CONDITION ASSESSMENT OF STRUCTURES
50
www.superarc.net
53. CONDITION ASSESSMENT OF STRUCTURES
52
www.superarc.net
NDT for detection of cracks/
delamination etc.
voids/
❑ Hammer sounding
❑ Chain dragging
❑ Ground penetrating radar
❑ Impact-echo
❑ Ultrasonic pulse velocity
❑ Radiographic testing
❑ Crack width measurement
54. NDT - Sounding
• A qualitative evaluation of concrete can
be easily obtained by just sounding it
(i.e. tapping it) with a hammer.
When the hammer is struck on good
concrete, a ringing sound is created.
On areas where delaminations or
cracks occur, the striking of the
hammer produces a drum-like sound.
The limitation of this method is that it
cannot detect defects that exist deep in
the member.
Also, defects lying under overlays are
also difficult to find.
•
•
•
•
CONDITION ASSESSMENT OF STRUCTURES
53
www.superarc.net
55. CONDITION ASSESSMENT OF STRUCTURES
54
www.superarc.net
NDT - Chain Dragging
• The objective is to detect regions where
the sound from dragging the chain
changes from a clear ringing sound
(sound deck) to a somewhat mute and
hollow sound (delaminated deck).
Chain drag is a relatively fast method
for determining the location of a
delamination
Chain Dragging is normally used on
large concrete surface areas, such as
bridge decks
The method typically rely on the
experience of the inspector to
differentiate the relative sounds of
similar materials
•
•
•
58. CONDITION ASSESSMENT OF STRUCTURES
57
www.superarc.net
Limitation
a) Smoothness of surface under test
b) Size , shape and rigidity of the specimen
c) Age of specimen
d) Surface and internal moisture condition of the
concrete
e) Type of coarse aggregate
f) Type of cement
g) Type of mould
h) Carbonation of concrete surface
78. CONDITION ASSESSMENT OF STRUCTURES
77
www.superarc.net
A test point is described as intact if the dominant return frequency corresponds to the bottom of the deck.
A delaminated point in the deck will theoretically demonstrate a shift in the return frequency toward higher values because
the wave reflections occur at shallower depths.
Depending on the extent and continuity of the delamination, the partitioning of the wave energy reflected
from the bottom of the deck and the delamination may vary.
82. The initial or incipient delamination, described as occasional separation within the depth of the slab, can be identified
through the presence of return frequencies associated with the reflections from both the bottom of the deck and the
delamination.
Progressed delamination is characterized by a single peak at a frequency corresponding to the depth of the
delamination.
Finally, in cases of wide or shallow delaminations, the dominant response of the deck to an impact is characterized by a
low frequency response of flexural-mode oscillations of the upper delaminated portion of the deck.
This response is almost always in the audible frequency range, unlike responses from the deck with incipient
delamination that may exist only in the higher frequency ranges (Gucunski et al. 2006; Cheng and Sansalone
1995; Lin and Sansalone 1996).
CONDITION ASSESSMENT OF STRUCTURES
81
www.superarc.net
83. CONDITION ASSESSMENT OF STRUCTURES
82
www.superarc.net
Ultrasonic Pulse Velocity
• Ultrasonic waves are very
similar to light waves in that
they can be reflected,
refracted, and focused.
Reflection and refraction
occurs when sound waves
interact with interfaces of
differing acoustic properties.
Ultrasonic reflections from the
presence of discontinuities or
geometric features enables
detection and location.
•
•
(USPV Test)
85. CONDITION ASSESSMENT OF STRUCTURES
84
www.superarc.net
This test is used for determination of the uniformity
of concrete in and between members.
Reference code: “Standard Test Method for Pulse
Velocity through Concrete” (ASTM C 597, 2016).
Principle:the velocity of an ultrasonic pulse through
any material depends upon the density, modulus of
elasticity and Poisson’s ratio of the material.
Higher is the velocity, better is the quality of concrete
USPV Test
86. CONDITION ASSESSMENT OF STRUCTURES
85
www.superarc.net
1- Pulse Velocity Determination
2- Concrete Quality Assessment
3- Establishing Homogeneity and Uniformity of Concrete
4- Measurement of Surface Crack Depth
5- Prediction of Compressive Strength of Concrete
Applications of UPV Testing for Concrete
87. CONDITION ASSESSMENT OF STRUCTURES
86
www.superarc.net
(a) Electrical pulse
generator
(b) Pair of transducers
(c) Amplifier
(d) Electronic timing
machine
UPSV Equipment
•Equipment should be capable of measuring transit time over path
lengths ranging from about 100 mm to the maximum thickness to be
inspected to an accuracy of ±1%
UPSV Contd…Equipment:
88. CONDITION ASSESSMENT OF STRUCTURES
87
www.superarc.net
UPSV Contd…. Methodology
Calibration: done by measuring transit time on
standard calibration rod.
Transducers arrangement: 3 methods
89. CONDITION ASSESSMENT OF STRUCTURES
88
www.superarc.net
Ultrasonic pulse velocity in concrete (UPV) ASTM C597
90. CONDITION ASSESSMENT OF STRUCTURES
89
www.superarc.net
Experimental Evaluation of Cracks in Concrete by Ultrasonic Pulse Velocity
92. CONDITION ASSESSMENT OF STRUCTURES
www.superarc.net 91
In order to conduct a reliable ultrasonic testing of concrete, the surface of concrete should
be clean, and free of dust. A suitable couplant is needed to establish an ideal connection
between concrete and UPV transducers. Special attention should be given to rebar in
concrete, since the wave travel speed in metal is much higher than in concrete. The
interpretation of test results in heavily reinforced concrete is somewhat difficult. The direct
configuration is the most ideal for getting reliable readings; however, the use of this
configuration is mainly limited to laboratory. In summary, the following issues should be
addressed before, during, and after performing the test:
1- Concrete Properties (aggregate size, type, and content)
2- Transducer Contact/ couplant material
3- Presence of Rebar
4- Sensor Configuration
UPV - Influencing Parameters
93. CONDITION ASSESSMENT OF STRUCTURES
92
www.superarc.net
3 Methods for Crack Depth Measurement in Concrete
What is Crack | Why Does Concrete Crack?
A crack is a linear fracture in concrete which extends partly or completely
through the member. In a concrete element, tensile stresses are initially carried by
the concrete and reinforcement. When the tensile stresses in the beam exceeds the
tensile capacity, the concrete cracks. After this point the tensile force is transferred
completely to the steel reinforcement.
Several issues can result in cracks in concrete, including:
❑ excessive external loads
❑ external restraint forces
❑ internal restraint forces
❑ differential movements
❑ settlements
In a concrete element, the crack (shrinkage, thermal, and service loads) width and
distribution is mainly controlled by steel reinforcement.
94. CONDITION ASSESSMENT OF STRUCTURES
93
www.superarc.net
Severity
Hairline cracks - less than 0.1 mm wide.
Narrow cracks - 0.1 mm to 0.3 mm wide.
Medium cracks - 0.3 mm to 1.0 mm wide.
Wide cracks - greater than 1.0 mm wide.
95. CONDITION ASSESSMENT OF STRUCTURES
94
www.superarc.net
How To Evaluate Concrete Cracks ?
Visual inspection and monitoring is the first step towards understanding the nature of
existing cracks, and the underlying causes.
96. CONDITION ASSESSMENT OF STRUCTURES
95
www.superarc.net
1. Crack Width
Crack severity on the surface of concrete is normally measured using a crack width
ruler (crack gauge). Depending on the opening of the cracks on the surface, cracks
can be described (as tiny as hairline, or severe (few millimeters opening).
2. Crack Depth
There are cases where structural engineers are interested in the crack depth
measurement. Crack depth is used to evaluate structural integrity, and verify
durability performance. Crack depth measurement can help repair contractor in
evaluating the repair costs.
Depending on the nature of the project, engineers rely on different intrusive and
non-intrusive techniques to estimate the crack depth.
97. CONDITION ASSESSMENT OF STRUCTURES
96
www.superarc.net
I. Visual Examination of Concrete Cores
Extracting core samples from the defects is considered a popular method among
inspectors and engineers. Core samples can provide information about the extent,
depth, and severity of cracks.
Crack Depth Measurement in Concrete
98. CONDITION ASSESSMENT OF STRUCTURES
97
www.superarc.net
II. Impact-Echo Method
In Impact-Echo test, a stress pulse is generated at the surface of the element. The
pulse spreads into the test object and is reflected by cracks, flaws or interfaces, and
boundaries. The surface response caused by the arrival of reflected waves, is
monitored using a high precision receiving transducer (Malhotra and Carino, 2004).
When stress waves travel within the concrete element, a part of emitted acoustic
waves by the stress pulse on the surface is reflected over the boundary layers, where
different the material stiffness changes. The data received by the transducer is
normally analyzed in the frequency domain to measure the wave speed and the
thickness. This procedure has been standardized as the ASTM C1383, “Standard Test
Method for Measuring the P-Wave Speed and the Thickness of Concrete Plates Using
the Impact-Echo Method”.
Impact-Echo can be used to assess the depth of surface cracks. To do so, an impact-
echo test setup with two transducers is needed.
99. CONDITION ASSESSMENT OF STRUCTURES
98
www.superarc.net
where L1 is the distance between the horizontal impact point and the crack; L2 denotes the
distance between the second sensor and the surface-opening crack; L3 represents the distance
between the impact point and the first sensor; VP is the P-wave velocity; and Δt denotes the
travel time for the P-wave from the start of the impact to its arrival to the transducer 2.
II. Impact-Echo Method
100. III. Ultrasonic Pulse Velocity (UPV)
Ultrasonic Pulse Velocity (UPV) is an effective
non-destructive testing (NDT) method for
quality control of concrete materials, and
detecting damages in structural components.
The UPV methods have traditionally been used
for the quality control of materials, mostly
homogeneous materials such as metals and
welded connections. With the recent
advancement in transducer technology, the test
has been widely accepted in testing concrete
materials. Ultrasonic testing of concrete is an
effective way for quality assessment and
uniformity, and crack depth estimation. The test
procedure has been standardized as “Standard
Test Method for Pulse Velocity through
Concrete” (ASTM C 597, 2016).
III. Ultrasonic Pulse Velocity (UPV)
CONDITION ASSESSMENT OF STRUCTURES
99
www.superarc.net
BS 1881 Part 203 1986 Recommendations for Measurement of Ultrasonic Pulse Velocity Through Concrete (London: British Standars Inst)
101. CONDITION ASSESSMENT OF STRUCTURES
100
www.superarc.net
Measuring Magnifier Crack Width Gauge
• Crack widths are normally limited to 0.2
mm or 0.3 mm in concrete structures.
Measuring Magnifier device enables
accurate determination of whether
cracks exceed this limit.
• Align the Crack Width Gauge where the
calibration and the crack are the same
width.
Record the width, length and location of
the crack.
•
•
–
–
–
Magnification 10x
Measuring range 20 mm x 0.1 mm
Field of View 32mm
Crack width measurement
102. CONDITION ASSESSMENT OF STRUCTURES
101
www.superarc.net
Crack width measurement
CRACK DETECTION MICROSCOPE • Specification:
–
–
–
Magnification x 40
Measuring Range 4 mm
Divisions 0.02mm
•
•
Measure crack widths in concrete.
Consisting of a high definition
Microscope connected to an adjustable
light source which provides a well-
illuminated image under all working
conditions.
The image is focused by turning the
knob on the side of the microscope and
the eyepiece can be rotated through
360 degrees to align with the direction
of the crack being examined.
The 4mm measurement has a lower
scale divided into 0.2mm divisions.
the maximum crack widths should not
exceed 0.3mm which is 15 divisions on
the scale for most types of
environment.
•
•
•
103. CONDITION ASSESSMENT OF STRUCTURES
102
www.superarc.net
NDT for corrosion assessment, location and
diameter of reinforcement
thickness
and cover
•
•
•
Cover meter
Half Cell Potential test
Concrete Resistivity test
104. CONDITION ASSESSMENT OF STRUCTURES
103
www.superarc.net
Cover meter test
• Cover meter test is used to assess the
location and estimate the diameter of
reinforcement bars and concrete cover.
Principle:
•
– based measurement of change of
an elctromagnetic field caused by
steel embedded in the concrete.
• Equipment:
– profometer comprise a search
head, meter and interconnecting
cable.
• The concrete surface is scanned, with
the search head kept in contact with it
while the meter indicates, by analogue
or digital means, the proximity of
reinforcement
106. CONDITION ASSESSMENT OF STRUCTURES
105
www.superarc.net
Cover meter test
• The cover meter applies a current
pulse
The instrument measures the
amplitude of the induced current, which
depends on the orientation, depth, and
size of the bar.
The search head is directional and
maximum signal is obtained when the
bar is aligned with the long axis of the
search head.
The pulse-induction technique is
uniquely stable, is not affected by
moisture in concrete or magnetic
aggregates, and is immune to
temperature variations and electrical
interference.
•
•
•
113. CONDITION ASSESSMENT OF STRUCTURES
112
www.superarc.net
Half-Cell Potential Method (ASTM C 876)
Principle:
• The electrical activity of the steel
reinforcement and the concrete leads
them to be considered as one half of
weak battery cell with the steel acting
as one electrode and the concrete as
the electrolyte.
• The electrical potential of a point on the
surface of steel reinforcing bar can be
measured comparing its potential with
that of copper - copper sulphate
reference electrode on the surface.
• Practically this achieved by connecting
a wire from one terminal of a voltmeter
to the reinforcement and another wire
to the copper sulphate reference
electrode.
• Then generally readings taken are
at grid of 1 x 1 m for slabs, walls
and at 0.5 m c/c for Column,
beams
114. CONDITION ASSESSMENT OF STRUCTURES
113
www.superarc.net
Half-Cell Potential Method (ASTM C876)
The results affected by: • Microcracks
– Localized corrosion can be
generated by microcracks, which
also modify the concrete resistivity,
consequently affecting the
corrosion potential measurement
• Degree of humidity in concrete
– More negative potentials result for
concrete with higher degree of
saturation.
• Stray currents
– The presence of stray currents will
significantly affect the
measurements of the half-cell
potential.
• Oxygen content near the
reinforcement
– The lack of oxygen near the
reinforcement results in more
negative potentials
115. CONDITION ASSESSMENT OF STRUCTURES
114
www.superarc.net
corrosion)
corrosion)
Measured
Potential
Ecorr values
Corrosion Condition
mV vs. SCE
<-426 <-500 Severe corrosion
<-276 <-350
High (>-90% risk of
-126
to
-275
-350
to
-200
Intermediate corrosion
risk
>-125 >-200
Low (10% risk of
CSE = Copper / Copper sulphate electrode,
i.e. the potential values are stated with the
respect to CSE
116. CONDITION ASSESSMENT OF STRUCTURES
115
www.superarc.net
Example of the Half Cell Potential test result
118. CONDITION ASSESSMENT OF STRUCTURES
117
www.superarc.net
Galvapulse - Surface Corrosion Rate System
typically been used in connection with:
Swimming pools
Bridges
Balconies
Parking houses
• The Galvanostatic Pulse
Measurements technique (GPM) was
first used in the field in 1988.
• It provides a solution to interpretation
problems found when the half cell
potential methods is used in some
environments, e.g. in wet concrete.
• estimation of corrosion rate as well,
which means how much reinforcement
steel is being dissolved per year.
• The GalvaPulse™ is a rapid, non-
destructive polarization technique for
the evaluation of reinforcement
corrosion rate as well as half-cell
potentials.
–
–
–
–
120. CONDITION ASSESSMENT OF STRUCTURES
www.superarc.net 119
Galvapulse - Surface Corrosion Rate System
Advantages • Measurements possible on uneven and
curved surfaces.
Measurement results in Excel-format
are easily transferred to PC for further
processing and presentation.
• Estimation of the corrosion rate in the
reinforcement can be made in less than
10 seconds.
Reliable evaluation of reinforcement
corrosion also in wet, carbonated or
inhibitor treated concrete.
Half cell potential and electrical
resistance of the cover layer are given.
Lightweight electrode / hand held
computer and easy to operate
software.
Durable Guard Ring system for
focusing the current field to the
reinforcement.
•
•
Threshold values
•
•
•
123. CONDITION ASSESSMENT OF STRUCTURES
www.superarc.net 122
Concrete Resistivity test
The Measurement Principle
Where
a is probe spacing [cm]
V is measured potential [V]
I is the current applied [A]
• measure the electrical resistivity of
concrete or rock in a non-destructive
test.
A current is applied to the two outer
probes, with the difference measured
by the two inner probes.
In concrete material with high electrical
resistivity the corrosion process will be
slow compared to concrete with low
resistivity in which the current can
easily pass between anode and
cathode areas
•
•
124. CONDITION ASSESSMENT OF STRUCTURES
www.superarc.net 123
Concrete Resistivity test result
• The electrical resistivity of concrete was
proposed as an effective parameter to
evaluate the risk of reinforcing steel
corrosion, particularly when corrosion is
induced by chloride attack
• The resistivity measurement is a useful
additional measurement to aid in
identifying problem areas or confirming
concerns about poor quality concrete.
• Measurements can only be considered
along side other measurements.
• Reinforcing bars will interfere with
resistivity measurements.
Limitation
• It is difficult to measure resistivity in
very close reinforcement
Carbonation may affect the
resistivity
It cannot be used where ambient
change in temperature is there.
Experience operator is required to
handle this equipment.
•
•
•
129. CONDITION ASSESSMENT OF STRUCTURES
128
www.superarc.net
Dust Sampling for Sulphate and Chloride Test
Maximum chloride content according to CIRIA 2002
Sulphate
Chloride
accepted limit is max. 4.0% max