Curing concrete involves maintaining moisture and temperature conditions to allow hydration of cement to occur. It prevents premature drying out which could limit strength development and durability. Effective curing methods include ponding, fogging, wet coverings, impervious sheets, membrane compounds and steam curing. Curing should continue until the concrete reaches adequate strength, typically a minimum of 7 days, and longer periods improve concrete properties. Temperature, cement type, element size and exposure conditions influence curing needs. Inadequate curing can limit strength and durability within 30-50mm of the surface.
Curing concrete involves maintaining moisture and temperature levels after placement to allow for proper hydration and hardening. Key curing methods include water curing through ponding, spraying or covering, as well as membrane curing when water is limited. Applying heat through steam curing can accelerate strength development but requires maintaining moisture. Proper curing for at least 7 days is important to ensure concrete reaches its designed strength and durability properties.
The document discusses different methods for repairing concrete members: grouting, guniting/shotcreting, epoxy injection, and jacketing. Grouting involves placing cementitious materials into cavities using pressure to fill voids and increase load capacity. Guniting uses a cement-sand mixture applied pneumatically to restore damaged surfaces. Epoxy injection establishes entry points to inject epoxy under pressure into cracks. Jacketing increases member size and stiffness by adding new concrete to encase the existing member, improving load capacity through composite action.
This document discusses curing of concrete, which involves maintaining moisture content and temperature to allow desired properties to develop. Proper curing increases strength, durability, and resistance to damage. It describes the hydration process where water reacts with cement compounds. A minimum of 38% water by weight of cement is needed for full hydration. Self-curing concrete uses chemicals to retain mixing water and prevent drying. Membrane-forming compounds form films on concrete surfaces that reduce evaporation and allow curing without applied water. Different types of compounds and their application procedures are outlined.
This document outlines 8 techniques for repairing cracks in concrete structures: 1) Sealing with epoxies, 2) Routing and sealing, 3) Stitching, 4) External stressing, 5) Overlays, 6) Grouting, 7) Blanketing, and 8) Autogenous healing. Sealing with epoxies involves injecting epoxy compounds into cracks at high pressure. Routing and sealing enlarges cracks and fills them with sealants. Stitching reestablishes tensile strength across major cracks using metal units drilled into crack walls. External stressing closes cracks by applying compression to overcome tensile stresses. Overlays provide a sealed surface for multiple cracks. Grouting is an alternative
Curing & prefabrication of concrete structures@hemadurgarao-IIIT Nuzvidhema3366
Curing concrete is an important process to ensure proper hydration of cement and development of strength. There are various curing methods like immersion, ponding, spraying, wet covering, and membrane curing. Membrane curing uses plastic sheeting or compounds to seal in moisture. Steam curing at higher temperatures accelerates strength gain but can cause retrogression of strength with fast hydration. Prefabricated construction involves dividing construction into standardized parts that are mass produced in a plant and assembled on site. This allows for parallel production, reduced time, and standardization.
Lightweight concrete has a lower density than normal concrete, ranging from 300-1850 kg/m3. There are three main types: lightweight aggregate concrete uses expanded aggregates; aerated concrete is produced by incorporating air bubbles; and no-fines concrete omits fine aggregates. Lightweight concrete provides benefits like improved thermal insulation, soundproofing, and fire resistance compared to normal concrete.
Curing concrete involves maintaining moisture and temperature levels after placement to allow for proper hydration and hardening. Key curing methods include water curing through ponding, spraying or covering, as well as membrane curing when water is limited. Applying heat through steam curing can accelerate strength development but requires maintaining moisture. Proper curing for at least 7 days is important to ensure concrete reaches its designed strength and durability properties.
The document discusses different methods for repairing concrete members: grouting, guniting/shotcreting, epoxy injection, and jacketing. Grouting involves placing cementitious materials into cavities using pressure to fill voids and increase load capacity. Guniting uses a cement-sand mixture applied pneumatically to restore damaged surfaces. Epoxy injection establishes entry points to inject epoxy under pressure into cracks. Jacketing increases member size and stiffness by adding new concrete to encase the existing member, improving load capacity through composite action.
This document discusses curing of concrete, which involves maintaining moisture content and temperature to allow desired properties to develop. Proper curing increases strength, durability, and resistance to damage. It describes the hydration process where water reacts with cement compounds. A minimum of 38% water by weight of cement is needed for full hydration. Self-curing concrete uses chemicals to retain mixing water and prevent drying. Membrane-forming compounds form films on concrete surfaces that reduce evaporation and allow curing without applied water. Different types of compounds and their application procedures are outlined.
This document outlines 8 techniques for repairing cracks in concrete structures: 1) Sealing with epoxies, 2) Routing and sealing, 3) Stitching, 4) External stressing, 5) Overlays, 6) Grouting, 7) Blanketing, and 8) Autogenous healing. Sealing with epoxies involves injecting epoxy compounds into cracks at high pressure. Routing and sealing enlarges cracks and fills them with sealants. Stitching reestablishes tensile strength across major cracks using metal units drilled into crack walls. External stressing closes cracks by applying compression to overcome tensile stresses. Overlays provide a sealed surface for multiple cracks. Grouting is an alternative
Curing & prefabrication of concrete structures@hemadurgarao-IIIT Nuzvidhema3366
Curing concrete is an important process to ensure proper hydration of cement and development of strength. There are various curing methods like immersion, ponding, spraying, wet covering, and membrane curing. Membrane curing uses plastic sheeting or compounds to seal in moisture. Steam curing at higher temperatures accelerates strength gain but can cause retrogression of strength with fast hydration. Prefabricated construction involves dividing construction into standardized parts that are mass produced in a plant and assembled on site. This allows for parallel production, reduced time, and standardization.
Lightweight concrete has a lower density than normal concrete, ranging from 300-1850 kg/m3. There are three main types: lightweight aggregate concrete uses expanded aggregates; aerated concrete is produced by incorporating air bubbles; and no-fines concrete omits fine aggregates. Lightweight concrete provides benefits like improved thermal insulation, soundproofing, and fire resistance compared to normal concrete.
Roller-compacted concrete (RCC) is a concrete that is mixed in a pugmill and placed with dump trucks and spread with bulldozers. It is compacted in lifts of 100-250mm thick using vibratory steel drum rollers. RCC does not require internal vibration and can be used for port, rail, highway, and industrial facilities. Some advantages are reduced cement, no formwork, and ability to maintain traffic flow during placement. Limitations include a rougher surface and difficulty compacting near edges.
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
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 epoxy injection and vacuum concrete techniques. It describes how epoxy injection can be used to repair cracks in concrete by bonding to the concrete and restoring structural strength. It also discusses polyurethane resins which can seal cracks and allow for some movement. The document then explains how vacuum concrete uses suction to remove excess water from fresh concrete, resulting in a lower water-cement ratio and higher strength without reducing workability.
This document presents information about vacuum concrete from a seminar. It introduces vacuum concrete as a technique to remove excess water from concrete to improve strength. It discusses the need for vacuum concrete to balance the contradictory requirements of workability and high strength. The key equipment used includes a vacuum pump, water separator, and filtering pads. Vacuum concrete can increase strength by 25% and is used in industrial floors, bridges, and other infrastructure. While it increases strength and durability, vacuum concrete has higher initial costs and requires specialized equipment and trained labor.
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>
This document discusses the workability of concrete. It defines workability as the ease with which concrete can be mixed, transported, placed, and compacted. Workability is associated with ease of flow, prevention of segregation, prevention of harshness, and prevention of bleeding. Several factors affect workability, including water content, aggregate size and shape, grading, porosity, admixtures, mixing time, and temperature. Workability is measured using tests such as slump testing and compacting factor testing. The document provides details on how these tests are performed and what the results indicate about a concrete mixture's workability.
This document provides an overview of consolidation in soils. It defines consolidation as a process where soils decrease in volume due to a reduction in water content without air replacing the water. Consolidation can occur due to external loads, self-weight, lowering of the water table, or desiccation. The document also describes normally consolidated and overconsolidated clays, coefficients of compressibility and consolidation, Terzaghi's one-dimensional consolidation theory, determination of preconsolidation pressure, and calculation of consolidation settlement.
The document discusses the gel/space ratio in concrete and its relationship to concrete strength. It states that the gel/space ratio governs the porosity of concrete, with a higher ratio resulting in lower porosity and higher strength. The gel/space ratio is affected by the water/cement ratio, as a higher water/cement ratio decreases the gel/space ratio by increasing porosity. Power's experiment showed the strength of concrete has a specific relationship to the gel/space ratio that can be calculated.
This document contains information about different types of shrinkage and creep that can occur in concrete. It discusses drying shrinkage, which occurs as water evaporates from concrete, causing it to shrink. Plastic shrinkage occurs while the concrete is still fresh and can cause cracking. Factors that influence each type of shrinkage are provided. The document also introduces creep, which is the slow deformation of concrete under stress over a long period of time. Consequences of creep such as loss of pre-stress and excessive deflection are mentioned.
Polymer concrete is a composite material made by impregnating a conventional concrete with monomers like methyl methacrylate or styrene, then polymerizing them to fill its pores and voids. This reduces porosity and improves strength and durability properties. Three main types are polymer impregnated concrete, polymer cement concrete, and polymer concrete. Polymer impregnated concrete uses precast concrete impregnated with monomer then polymerized. It exhibits higher strength, stiffness, and durability compared to conventional concrete.
Curing plays an important role in the strength and durability of concrete. It involves preventing moisture loss from concrete to allow the hydration process to continue and gain strength. Some common curing methods include ponding, sprinkling with water, using wet coverings like burlap or plastic sheets, sealing the surface, and steam curing. Curing should be continuous for at least 7 days for normal concrete or 10-14 days if exposed to dry, hot conditions or if blended cements are used. Maintaining moisture is especially important in cold weather to prevent freezing.
The document discusses different types of lightweight and heavyweight concrete. It defines lightweight concrete as having a density less than 1850 kg/m3 and a compressive strength over 17 MPa. Lightweight concrete uses porous lightweight aggregates like expanded shale, clay or slate to reduce weight. Heavyweight concrete uses dense aggregates like barites or magnetite to increase density for radiation shielding. The document provides details on the composition, properties and uses of different types of lightweight and heavyweight concrete.
(1) The document discusses the durability and serviceability of concrete. It defines durability as the ability to resist weathering and chemical attacks. (2) The resistance of concrete depends on its quality, constituent materials, and curing process. Well-made concrete that is properly compacted and cured can remain durable if micro-cracks do not connect to the surface. (3) The document presents three holistic models of deterioration in reinforced concrete. The first two models describe a two-stage process where micro-cracks first interconnect, then allow water and chemicals to penetrate and cause damage. The third model emphasizes the role of water cement ratio and the interaction of porosity, chemicals, and intermittent water presence in causing
Curing concrete is important to allow the cement hydration process to continue and develop strength over time. Proper curing ensures concrete reaches its designed strength and durability by controlling moisture loss. Common curing methods include water curing through ponding, sprinkling or wet coverings; membrane curing using plastic sheeting or curing compounds; and steam curing to accelerate strength gain. Curing should continue for at least 7 days for normal concrete and 14 days if blended cements are used. Inadequate curing can lead to reduced strength, increased permeability and poor durability.
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 the working stress method for designing reinforced concrete structures. It defines key terms like neutral axis, lever arm, and moment of resistance. It describes the assumptions and steps of the working stress method, including designing for under-reinforced, balanced, and over-reinforced beam sections. The document also discusses limitations of the working stress method and introduces the limit state method as a more modern approach.
The document discusses the durability of concrete and the factors that affect it. It defines durability as the ability of concrete to resist weathering, chemical attack, and abrasion while maintaining its desired properties. The main factors discussed are abrasion, biological factors, temperature effects, freezing and thawing, and various types of chemical attacks including carbonation, chloride attack, acid attack, and sulfate attack. Prevention and mitigation methods are provided for each factor.
This document discusses various methods for curing concrete, which is important for developing the concrete's strength, stability, and durability. It describes three main categories of curing methods: using impermeable membranes to minimize moisture loss; continuously wetting the surface to prevent moisture loss; and methods that keep the surface moist while also raising the temperature to increase the rate of strength gain. Specific curing methods discussed include leaving formwork in place, applying curing compounds, using internal curing compounds, water curing through ponding or sprinkling, and using wet coverings like fabrics. Proper curing requires providing adequate moisture for continued hydration over the required curing period.
The document discusses various methods for curing concrete, including maintaining moisture through ponding, immersion, fogging, or wet coverings. It also discusses methods that reduce moisture loss such as using impervious paper, plastic sheets, or curing compounds. Accelerated curing methods that provide additional heat and moisture like steam curing are also described. Proper curing is important for ensuring hydration of cement and allowing concrete to reach its desired strength and durability properties. Inadequate curing can result in reduced strength and durability in the surface layers of concrete.
Roller-compacted concrete (RCC) is a concrete that is mixed in a pugmill and placed with dump trucks and spread with bulldozers. It is compacted in lifts of 100-250mm thick using vibratory steel drum rollers. RCC does not require internal vibration and can be used for port, rail, highway, and industrial facilities. Some advantages are reduced cement, no formwork, and ability to maintain traffic flow during placement. Limitations include a rougher surface and difficulty compacting near edges.
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
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 epoxy injection and vacuum concrete techniques. It describes how epoxy injection can be used to repair cracks in concrete by bonding to the concrete and restoring structural strength. It also discusses polyurethane resins which can seal cracks and allow for some movement. The document then explains how vacuum concrete uses suction to remove excess water from fresh concrete, resulting in a lower water-cement ratio and higher strength without reducing workability.
This document presents information about vacuum concrete from a seminar. It introduces vacuum concrete as a technique to remove excess water from concrete to improve strength. It discusses the need for vacuum concrete to balance the contradictory requirements of workability and high strength. The key equipment used includes a vacuum pump, water separator, and filtering pads. Vacuum concrete can increase strength by 25% and is used in industrial floors, bridges, and other infrastructure. While it increases strength and durability, vacuum concrete has higher initial costs and requires specialized equipment and trained labor.
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>
This document discusses the workability of concrete. It defines workability as the ease with which concrete can be mixed, transported, placed, and compacted. Workability is associated with ease of flow, prevention of segregation, prevention of harshness, and prevention of bleeding. Several factors affect workability, including water content, aggregate size and shape, grading, porosity, admixtures, mixing time, and temperature. Workability is measured using tests such as slump testing and compacting factor testing. The document provides details on how these tests are performed and what the results indicate about a concrete mixture's workability.
This document provides an overview of consolidation in soils. It defines consolidation as a process where soils decrease in volume due to a reduction in water content without air replacing the water. Consolidation can occur due to external loads, self-weight, lowering of the water table, or desiccation. The document also describes normally consolidated and overconsolidated clays, coefficients of compressibility and consolidation, Terzaghi's one-dimensional consolidation theory, determination of preconsolidation pressure, and calculation of consolidation settlement.
The document discusses the gel/space ratio in concrete and its relationship to concrete strength. It states that the gel/space ratio governs the porosity of concrete, with a higher ratio resulting in lower porosity and higher strength. The gel/space ratio is affected by the water/cement ratio, as a higher water/cement ratio decreases the gel/space ratio by increasing porosity. Power's experiment showed the strength of concrete has a specific relationship to the gel/space ratio that can be calculated.
This document contains information about different types of shrinkage and creep that can occur in concrete. It discusses drying shrinkage, which occurs as water evaporates from concrete, causing it to shrink. Plastic shrinkage occurs while the concrete is still fresh and can cause cracking. Factors that influence each type of shrinkage are provided. The document also introduces creep, which is the slow deformation of concrete under stress over a long period of time. Consequences of creep such as loss of pre-stress and excessive deflection are mentioned.
Polymer concrete is a composite material made by impregnating a conventional concrete with monomers like methyl methacrylate or styrene, then polymerizing them to fill its pores and voids. This reduces porosity and improves strength and durability properties. Three main types are polymer impregnated concrete, polymer cement concrete, and polymer concrete. Polymer impregnated concrete uses precast concrete impregnated with monomer then polymerized. It exhibits higher strength, stiffness, and durability compared to conventional concrete.
Curing plays an important role in the strength and durability of concrete. It involves preventing moisture loss from concrete to allow the hydration process to continue and gain strength. Some common curing methods include ponding, sprinkling with water, using wet coverings like burlap or plastic sheets, sealing the surface, and steam curing. Curing should be continuous for at least 7 days for normal concrete or 10-14 days if exposed to dry, hot conditions or if blended cements are used. Maintaining moisture is especially important in cold weather to prevent freezing.
The document discusses different types of lightweight and heavyweight concrete. It defines lightweight concrete as having a density less than 1850 kg/m3 and a compressive strength over 17 MPa. Lightweight concrete uses porous lightweight aggregates like expanded shale, clay or slate to reduce weight. Heavyweight concrete uses dense aggregates like barites or magnetite to increase density for radiation shielding. The document provides details on the composition, properties and uses of different types of lightweight and heavyweight concrete.
(1) The document discusses the durability and serviceability of concrete. It defines durability as the ability to resist weathering and chemical attacks. (2) The resistance of concrete depends on its quality, constituent materials, and curing process. Well-made concrete that is properly compacted and cured can remain durable if micro-cracks do not connect to the surface. (3) The document presents three holistic models of deterioration in reinforced concrete. The first two models describe a two-stage process where micro-cracks first interconnect, then allow water and chemicals to penetrate and cause damage. The third model emphasizes the role of water cement ratio and the interaction of porosity, chemicals, and intermittent water presence in causing
Curing concrete is important to allow the cement hydration process to continue and develop strength over time. Proper curing ensures concrete reaches its designed strength and durability by controlling moisture loss. Common curing methods include water curing through ponding, sprinkling or wet coverings; membrane curing using plastic sheeting or curing compounds; and steam curing to accelerate strength gain. Curing should continue for at least 7 days for normal concrete and 14 days if blended cements are used. Inadequate curing can lead to reduced strength, increased permeability and poor durability.
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 the working stress method for designing reinforced concrete structures. It defines key terms like neutral axis, lever arm, and moment of resistance. It describes the assumptions and steps of the working stress method, including designing for under-reinforced, balanced, and over-reinforced beam sections. The document also discusses limitations of the working stress method and introduces the limit state method as a more modern approach.
The document discusses the durability of concrete and the factors that affect it. It defines durability as the ability of concrete to resist weathering, chemical attack, and abrasion while maintaining its desired properties. The main factors discussed are abrasion, biological factors, temperature effects, freezing and thawing, and various types of chemical attacks including carbonation, chloride attack, acid attack, and sulfate attack. Prevention and mitigation methods are provided for each factor.
This document discusses various methods for curing concrete, which is important for developing the concrete's strength, stability, and durability. It describes three main categories of curing methods: using impermeable membranes to minimize moisture loss; continuously wetting the surface to prevent moisture loss; and methods that keep the surface moist while also raising the temperature to increase the rate of strength gain. Specific curing methods discussed include leaving formwork in place, applying curing compounds, using internal curing compounds, water curing through ponding or sprinkling, and using wet coverings like fabrics. Proper curing requires providing adequate moisture for continued hydration over the required curing period.
The document discusses various methods for curing concrete, including maintaining moisture through ponding, immersion, fogging, or wet coverings. It also discusses methods that reduce moisture loss such as using impervious paper, plastic sheets, or curing compounds. Accelerated curing methods that provide additional heat and moisture like steam curing are also described. Proper curing is important for ensuring hydration of cement and allowing concrete to reach its desired strength and durability properties. Inadequate curing can result in reduced strength and durability in the surface layers of concrete.
This document discusses various methods of curing concrete, including water curing, membrane curing, steam curing, and electrical curing. It notes that curing allows for continuous hydration and strength gain in concrete. Proper curing retains moisture on the surface and prevents early drying out, leading to increased strength and durability. A new technique called "drip curing" is also introduced, which can reduce water consumption during curing by up to 80% through the use of multilayer sheets that drip water onto the concrete surface.
This document discusses hot weather concreting and provides guidelines and precautions. Detrimental hot weather conditions include high ambient temperature, concrete temperature, low relative humidity, and high wind speed. Precautions should be taken such as cooling concrete materials, using supplementary cementitious materials, and promptly transporting, placing, and finishing the concrete. Plastic shrinkage cracking can occur if the rate of evaporation exceeds thresholds, so fogging and windbreaks are recommended. Proper curing, including water spraying or saturated fabric, is especially important in hot weather to prevent drying of concrete surfaces.
Module on Special and high performance concreteErankajKumar
The document discusses different types of special concretes used in construction, including grouting, guniting, underwater concreting, and hot and cold weather concreting. Grouting involves injecting cement grout into cracks and voids to improve stability. Guniting uses a cement-sand mix applied at high pressure to repair damaged concrete. Underwater concreting requires special techniques like the tremie method and uses additives to allow placement under water. Hot and cold weather concreting require precautions like cooling or heating aggregates and protecting fresh concrete to account for temperature effects.
This document discusses concrete construction in extreme hot and cold weather conditions in India. It addresses the challenges of hot weather concreting such as increased water demand, accelerated slump loss, and increased risk of plastic shrinkage cracking. Recommendations for hot weather concreting include cooling the concrete, reducing placement time, and prompt curing. Cold weather concreting risks include reduced strength if water freezes within concrete. Recommendations include protecting concrete from freezing, using accelerants, and maintaining minimum curing temperatures. Proper planning, materials, and protection methods can help produce quality concrete despite temperature extremes.
Cement concrete is a composite material consisting of a binding material (cement or lime), aggregates (fine and coarse), water, and admixtures. The cement and water form a paste that coats the aggregates and binds them together. Concrete can be classified based on its constituents, method of production, place of casting, and bulk density. Proper curing is important for concrete to gain strength and hardness through hydration. Common curing methods include water curing, membrane curing, and steam curing. The water-cement ratio significantly impacts concrete strength, with lower ratios producing stronger concrete.
Curing of concrete is important to prevent rapid evaporation of water from the concrete surface. Several curing methods are discussed, including ponding, sprinkling, wet coverings like burlap or cotton mats, sealing the surface with waterproof sheets or liquid compounds, and steam curing. Steam curing allows for early strength gain and hydration, especially in cold weather, by applying live steam at atmospheric pressure within an enclosure or using high pressure steam autoclaves.
Curing of concrete is important to prevent rapid evaporation of water from the concrete surface. Several curing methods are discussed, including ponding, sprinkling, wet coverings like burlap or cotton mats, sealing the surface with waterproof sheets or liquid compounds, and steam curing. Steam curing allows for early strength gain and hydration, especially in cold weather, by applying live steam at atmospheric pressure within an enclosure or using high pressure steam autoclaves.
This document discusses various concrete curing methods including formwork, plastic sheeting, internal curing compounds, ponding, and sprinkling. Formwork and plastic sheeting can effectively cure concrete if kept moist, especially in hot dry weather. Internal curing compounds inhibit moisture loss to improve strength and reduce shrinkage. Ponding is effective for flat surfaces if a water supply is available. Sprinkling or fog curing can be used on most surfaces but require major water and drainage systems to prevent waste. The document provides details on properly applying the different curing methods.
Shrinkage and plastic of concrete samples.pptGKRathod2
The document discusses various topics related to concrete, including destructive and non-destructive tests to determine concrete strength, factors affecting setting time and workability, methods to prevent issues like segregation and bleeding during concrete placement, and different curing techniques to promote strength development and durability. It provides details on tests like rebound hammer, ultrasonic pulse velocity and compression tests. It also explains concepts like slump loss, factors influencing cohesiveness, and precautions needed for hot weather concreting to prevent plastic shrinkage cracks.
The document discusses various topics related to concrete, including destructive and non-destructive tests to determine concrete strength, factors affecting setting time and workability, methods to prevent issues like segregation and bleeding during concrete placement, and different curing techniques to promote strength development and durability. It provides details on tests like rebound hammer, ultrasonic pulse velocity and compression tests. It also explains concepts like slump loss, influence of curing, and how to prevent plastic shrinkage cracks.
Curing plays an important role in the strength and durability of concrete. It involves keeping concrete moist and maintaining its temperature to allow hydration to occur. There are several curing methods, including ponding, sprinkling water, using wet coverings like burlap or plastic sheets, applying membrane compounds, steam curing, and using water-based curing compounds. Proper curing is especially important in extreme weather conditions like cold temperatures to prevent freezing and allow concrete to gain adequate strength over time.
Concrete is a composite material made of aggregates, sand, cement and water. It has many useful properties such as versatility, durability and fire resistance which make it widely used in construction. Fresh concrete must have adequate workability and consistency to be properly mixed, placed and consolidated. Proper curing is also important to allow the cement to fully hydrate and gain strength over time. While concrete has advantages, it also has disadvantages like low tensile strength and requires careful mixing to ensure uniformity.
Curing is the process of controlling the rate and extent of moisture loss from concrete during cement hydration. It is important to cure concrete for a reasonable period of time, such as days or weeks, to allow hydration to occur and for the concrete to achieve its potential strength and durability. There are several curing methods, including impermeable membrane curing using plastic sheeting or curing compounds to minimize moisture loss, and water curing through ponding, sprinkling, or wet coverings to continuously wet the exposed concrete surface and prevent moisture loss. The appropriate curing method depends on factors like the type of concrete member, the environment, and whether formwork can be retained.
Curing concrete involves maintaining moisture content and temperature to allow hydration to occur. Proper curing increases strength, durability, and resistance to damage. Self-curing concrete uses compounds that form a film and retain mixing water to allow hydration to continue without external curing. These compounds are applied as a spray and form a hydrophobic layer that prevents water evaporation, ensuring cement hydration can complete. Proper application of curing compounds is important to fully cure concrete and provide optimal properties.
Hot weather is defined as any period with high temperatures that require special precautions for concrete. High temperatures can cause rapid drying of concrete and accelerated setting, potentially leading to cracking. It is important to account for hot weather conditions when planning concrete projects, as high heat can increase water demand and accelerate setting. To successfully place concrete during hot weather, the key is recognizing affecting factors and minimizing their impacts, such as modifying mix designs, reducing cement content, limiting water addition, starting finishing quickly, and adequately curing the concrete.
Temperature and shrinkage effect on structural analysis - 10.01.03.072Mohammed_Shakib
This document summarizes the effects of shrinkage and temperature changes on concrete, including:
- Shrinkage occurs as free water evaporates from concrete, causing cracks if not controlled. It can cause stresses in statically indeterminate structures and loss of pre-stress.
- The amount of shrinkage depends on water-cement ratio, cement content, aggregate type and content. It can be reduced by decreasing water, increasing aggregate, and proper curing.
- Temperature changes cause expansion and contraction that can also cause cracks. The coefficient of thermal expansion is typically 4-7x10-6 per °F.
- Both shrinkage and temperature effects are important to consider in concrete design to
Fresh concrete -building materials for engineersmusadoto
General introduction
CONCRETE
is a building Material made from a mixture of gravel ,sand ,cement,water and air ,forming a stone like mass on hardenning.
FRESH CONCRETE
It is a concrete that has not reached the final setting time.
Using recycled concrete aggregates (RCA) for pavements is crucial to achieving sustainability. Implementing RCA for new pavement can minimize carbon footprint, conserve natural resources, reduce harmful emissions, and lower life cycle costs. Compared to natural aggregate (NA), RCA pavement has fewer comprehensive studies and sustainability assessments.
Literature Review Basics and Understanding Reference Management.pptxDr Ramhari Poudyal
Three-day training on academic research focuses on analytical tools at United Technical College, supported by the University Grant Commission, Nepal. 24-26 May 2024
A SYSTEMATIC RISK ASSESSMENT APPROACH FOR SECURING THE SMART IRRIGATION SYSTEMSIJNSA Journal
The smart irrigation system represents an innovative approach to optimize water usage in agricultural and landscaping practices. The integration of cutting-edge technologies, including sensors, actuators, and data analysis, empowers this system to provide accurate monitoring and control of irrigation processes by leveraging real-time environmental conditions. The main objective of a smart irrigation system is to optimize water efficiency, minimize expenses, and foster the adoption of sustainable water management methods. This paper conducts a systematic risk assessment by exploring the key components/assets and their functionalities in the smart irrigation system. The crucial role of sensors in gathering data on soil moisture, weather patterns, and plant well-being is emphasized in this system. These sensors enable intelligent decision-making in irrigation scheduling and water distribution, leading to enhanced water efficiency and sustainable water management practices. Actuators enable automated control of irrigation devices, ensuring precise and targeted water delivery to plants. Additionally, the paper addresses the potential threat and vulnerabilities associated with smart irrigation systems. It discusses limitations of the system, such as power constraints and computational capabilities, and calculates the potential security risks. The paper suggests possible risk treatment methods for effective secure system operation. In conclusion, the paper emphasizes the significant benefits of implementing smart irrigation systems, including improved water conservation, increased crop yield, and reduced environmental impact. Additionally, based on the security analysis conducted, the paper recommends the implementation of countermeasures and security approaches to address vulnerabilities and ensure the integrity and reliability of the system. By incorporating these measures, smart irrigation technology can revolutionize water management practices in agriculture, promoting sustainability, resource efficiency, and safeguarding against potential security threats.
Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapte...University of Maribor
Slides from talk presenting:
Aleš Zamuda: Presentation of IEEE Slovenia CIS (Computational Intelligence Society) Chapter and Networking.
Presentation at IcETRAN 2024 session:
"Inter-Society Networking Panel GRSS/MTT-S/CIS
Panel Session: Promoting Connection and Cooperation"
IEEE Slovenia GRSS
IEEE Serbia and Montenegro MTT-S
IEEE Slovenia CIS
11TH INTERNATIONAL CONFERENCE ON ELECTRICAL, ELECTRONIC AND COMPUTING ENGINEERING
3-6 June 2024, Niš, Serbia
Introduction- e - waste – definition - sources of e-waste– hazardous substances in e-waste - effects of e-waste on environment and human health- need for e-waste management– e-waste handling rules - waste minimization techniques for managing e-waste – recycling of e-waste - disposal treatment methods of e- waste – mechanism of extraction of precious metal from leaching solution-global Scenario of E-waste – E-waste in India- case studies.
ACEP Magazine edition 4th launched on 05.06.2024Rahul
This document provides information about the third edition of the magazine "Sthapatya" published by the Association of Civil Engineers (Practicing) Aurangabad. It includes messages from current and past presidents of ACEP, memories and photos from past ACEP events, information on life time achievement awards given by ACEP, and a technical article on concrete maintenance, repairs and strengthening. The document highlights activities of ACEP and provides a technical educational article for members.
A review on techniques and modelling methodologies used for checking electrom...nooriasukmaningtyas
The proper function of the integrated circuit (IC) in an inhibiting electromagnetic environment has always been a serious concern throughout the decades of revolution in the world of electronics, from disjunct devices to today’s integrated circuit technology, where billions of transistors are combined on a single chip. The automotive industry and smart vehicles in particular, are confronting design issues such as being prone to electromagnetic interference (EMI). Electronic control devices calculate incorrect outputs because of EMI and sensors give misleading values which can prove fatal in case of automotives. In this paper, the authors have non exhaustively tried to review research work concerned with the investigation of EMI in ICs and prediction of this EMI using various modelling methodologies and measurement setups.
Harnessing WebAssembly for Real-time Stateless Streaming PipelinesChristina Lin
Traditionally, dealing with real-time data pipelines has involved significant overhead, even for straightforward tasks like data transformation or masking. However, in this talk, we’ll venture into the dynamic realm of WebAssembly (WASM) and discover how it can revolutionize the creation of stateless streaming pipelines within a Kafka (Redpanda) broker. These pipelines are adept at managing low-latency, high-data-volume scenarios.
Embedded machine learning-based road conditions and driving behavior monitoringIJECEIAES
Car accident rates have increased in recent years, resulting in losses in human lives, properties, and other financial costs. An embedded machine learning-based system is developed to address this critical issue. The system can monitor road conditions, detect driving patterns, and identify aggressive driving behaviors. The system is based on neural networks trained on a comprehensive dataset of driving events, driving styles, and road conditions. The system effectively detects potential risks and helps mitigate the frequency and impact of accidents. The primary goal is to ensure the safety of drivers and vehicles. Collecting data involved gathering information on three key road events: normal street and normal drive, speed bumps, circular yellow speed bumps, and three aggressive driving actions: sudden start, sudden stop, and sudden entry. The gathered data is processed and analyzed using a machine learning system designed for limited power and memory devices. The developed system resulted in 91.9% accuracy, 93.6% precision, and 92% recall. The achieved inference time on an Arduino Nano 33 BLE Sense with a 32-bit CPU running at 64 MHz is 34 ms and requires 2.6 kB peak RAM and 139.9 kB program flash memory, making it suitable for resource-constrained embedded systems.
1. Curing Concrete
Curing Concrete
Curing can be defined as a procedure for insuring
the hydration of the Portland cement in newly
placed concrete. It generally implies control of
moisture loss and sometimes of temperature.
The hydration of Portland cement is the chemical
reaction between grains of Portland cement and
water to form the hydration product, cement gel:
and cement gel can be laid down only in water-
filled space.
Hydration can proceed until all the cement reaches
its maximum degree of hydration or until all the
space available for the hydration product is filled
by cement gel, whichever limit is reached first.
2. Curing Concrete
Curing Concrete
A typical definition of curing is ‘the process of
preventing the loss of moisture from the concrete
whilst maintaining a satisfactory temperature
regime’. This particular definition adds that the
curing regime should prevent the development of
high temperature gradients within the concrete.
Curing requires adequate:
• Moisture
• Heat
• Time
If any of these factors are neglected, the desired
properties will not develop
3. Curing Concrete
Curing methods
1.Methods that maintain the presence of
mixing water in the concrete during
the early hardening period. These
include
Ponding
Immersion
Spraying or Fogging
Saturated wet coverings.
Concrete can be kept moist three curing methods:
4. Curing Concrete
Curing methods
2. Methods that reduce the loss of mixing
water from the surface of the concrete.
This can be done by covering the
concrete with
Impervious paper
plastic sheets
By applying membrane-forming curing
compounds.
Concrete can be kept moist three curing methods:
5. Curing Concrete
Curing methods
3. Methods that accelerate strength gain
by supplying heat and additional
moisture to the concrete. This is
usually accomplished with
Live steam,
heating coils
Electrically heated forms or pads.
The method or combination of methods
chosen depends on factors such as
availability of curing materials, size,
shape, and age of concrete,
production facilities (in place or in a
plant), and economics.
Concrete can be kept moist three curing methods:
6. Curing Concrete
Curing methods
-On flat surfaces, such as
pavements and floors, concrete
can be cured by Ponding. Earth or
sand dikes around the perimeter
of the concrete surface can retain
a pond of water.
-The most thorough method of
curing with water consists of total
immersion of the finished
concrete element. This method is
commonly used in the laboratory
for curing concrete test
specimens.
Ponding and Immersion
7. Curing Concrete
Curing methods
-Fogging and sprinkling with water
are excellent methods of curing
when the ambient temperature is
well above freezing and the
humidity is low. A fine fog mist is
frequently applied through a
system of nozzles or sprayers to
raise the relative humidity of the
air over flatwork, thus slowing
evaporation from the surface.
- Fogging is applied to minimize
plastic shrinkage cracking until
finishing operations are complete.
Fogging and Sprinkling
8. Curing Concrete
Curing methods
-Fabric coverings saturated with
water, such as burlap, cotton
mats, rugs, or other moisture-
retaining fabrics, are commonly
used for curing. Treated
burlaps that reflect light and are
resistant to rot and fire are
available.
Wet Coverings
9. Curing Concrete
Curing methods
Impervious paper for curing
concrete consists of two sheets
of Kraft paper cemented
together by a bituminous
adhesive with fiber
reinforcement. Such paper,
conforming to ASTM C 171
(AASHTO M 171), is an
efficient means of curing
horizontal surfaces and
structural concrete of relatively
simple shapes.
Impervious Paper
10. Curing Concrete
Curing methods
-Plastic sheet materials, such
as polyethylene film, can be
used to cure concrete.
Polyethylene film is a
lightweight, effective
moisture retarder and is
easily applied to complex as
well as simple shapes
Plastic Sheets
11. Curing Concrete
Curing methods
Liquid membrane-forming
materials can be used to
retard or reduce
evaporation of moisture
from concrete. They are the
most practical and most
widely used method for
curing not only freshly
placed concrete but also for
extending curing of concrete
after removal of forms or
after initial moist curing.
Membrane-Forming Curing Compounds
12. Curing Concrete
Curing methods
-Forms provide satisfactory protection
against loss of moisture if the top
exposed concrete surfaces are kept wet.
- The forms should be left on the concrete
as long as practical. Wood forms left in
place should be kept moist by sprinkling,
especially during hot, dry weather. If this
cannot be done, they should be
removed as soon as practical and
another curing method started without
delay.
Forms Left in Place
13. Curing Concrete
Curing methods
Steam curing is
advantageous where early
strength gain in concrete is
important or where additional
heat is required to
accomplish hydration, as in
cold weather. Two methods
of steam curing are used: live
steam at atmospheric
pressure (for enclosed cast-
in-place structures and large
precast concrete units) and
high-pressure steam in
autoclaves (for small
manufactured units).
Steam Curing
14. Curing Concrete
Curing methods
Electrical, hot oil, microwave and infrared
curing methods have been available for
accelerated and normal curing of concrete for
many years. Electrical curing methods include
a variety of techniques:
(1) Use of the concrete itself as the electrical
conductor,
(2) Use of reinforcing steel as the heating
element,
(3) Use of a special wire as the heating
element,
(4) Electric blankets, and
(5) The use of electrically heated steel forms
(presently the most popular method).
Electrical, Oil, Microwave, and Infrared Curing
15. Curing Concrete
The intention of curing is to protect concrete
against:
• Premature drying out, particularly by solar
radiation and wind (plastic shrinkage)
• leaching out by rain and flowing water
• Rapid cooling during the first few days
after placing
• High internal thermal gradients
• Low temperature or frost
• Vibration and impact which may disrupt the
concrete and interfere with bond to
reinforcement.
Why cure concrete
16. Curing Concrete
The depth of the surface
zone directly affected by
curing can be up to 20 mm
in temperate climatic
conditions, and up to 50 mm
in more extreme arid
conditions. Properties of the
concrete beyond this zone
are unlikely to be affected
significantly by normal
curing.
Why cure concrete
17. Curing Concrete
The rate of evaporation of water from
the surface, taking into account the
combined influences of the ambient
temperature and relative humidity, the
concrete temperature, and the wind
velocity can be estimated from Figure
below taken from ACI 308. This
standard requires that curing measures
are taken if the predicted rate of
evaporation exceeds 1.0 kg/m2/h, to
prevent plastic shrinkage cracking, but
also recommends that such measures
may be needed if the rate exceeds 0.5
kg/m2/h.
Why cure concrete
19. Curing Concrete
The question is how early water
can be applied over concrete
surface so that uninterrupted and
continued hydration takes place,
without causing interference with
the W/C ratio.
The answer is that first of all,
concrete should not be allowed
to dry fast in any situation.
When to start curing
20. Curing Concrete
This condition should be maintained for 24
hours or at least till the final setting time
of cement at which duration the concrete
will have assumed the final volume. Even if
water is poured after this time, it is not
going to interfere with the W/C ratio.
However, the best practice is to keep the
concrete under the wet gunny bag for 24
hours and then commence water curing by
way of ponding or spraying.
When to start curing
21. Curing Concrete
This depends upon:
• The reason for curing (plastic shrinkage,
temperature control, strength, durability,
etc.)
• The size of the element
• The type of concrete (especially rate of
hardening)
• The ambient conditions during curing
• The exposure conditions to be expected
after curing
• The requirements of the specification
How long curing should be
applied?
22. Curing Concrete
Regarding how long to cure it is difficult to
set a limit. Since all the desirable properties
of concrete are improved by curing, the
curing period should be as long as practical.
For general guidance, concrete must be
cured till it attains 70% of specified strength.
At lower temperature curing period must be
increased.
Concrete keeps getting HARDER AND
STRONGER over TIME. For better strength
and durability, cure concrete for 7 DAYS.
The LONGER concrete is cured, the closer
it will be to its best possible strength and
durability.
How long curing should be
applied?
24. Curing Concrete
Cements, or combinations, containing fly
ash (pfa), blast furnace slag (ggbs),
limestone filler (>5 per cent), or condensed
silica fume react more slowly than plain
Portland cement, particularly in cold
weather. Concretes containing blended
cements should therefore be cured
thoroughly and for a longer period than for
PC concrete, particularly if the potential
durability benefits are to be obtained in the
near-surface and cover zone. Concrete
containing condensed silica fume or
metakaolin exhibits only minimal bleeding
and thus requires early protection to prevent
plastic shrinkage cracking.
The effect of cement type
25. Curing Concrete
The following circumstances warrant
particular consideration of curing needs:
• Horizontal surfaces
• Dry, hot, windy conditions (one or more
of these)
• Wear-resistant floors
• High-strength concrete (initial curing is
especially important)
When is curing of particular
importance?
26. Curing Concrete
The hardening of concrete is a chemical
reaction – the rate of this reaction increases
with temperature but so does the rate of
evaporation from an exposed concrete
surface.
The rate of reaction at 35°C is about twice
that at 20°C which is, in itself, about twice
that at 10°C. The ultimate strength of
concrete cured at low temperature (e.g. in
winter) is generally greater than that of
concrete cured at a higher temperature (e.g.
in summer); but extremes of temperature
generally have a negative effect.
Effect of temperature
27. Curing Concrete
The slow rate of reaction at low
temperatures means the concrete must be
cured for a longer period to achieve the
desired degree of reaction.
The fast rate of reaction at high
temperatures gives relatively high early
strengths but the long-term strength and
durability are generally reduced.
The optimum temperature required to
produce the maximum 28-day strength,
based on small laboratory specimens, is
said to be approximately 13°C (Neville and
Brooks, 1987) and ambient temperatures of
15–25°C are generally considered to be
most suitable for concreting operations.
Effect of temperature
29. Curing Concrete
Hydration will proceed, to some extent, at
temperatures down to as low as –10°C.
Nevertheless, little strength will develop
below 0°C, and below 5°C the early
strength development is greatly retarded
(ACI 308). Even in the temperature range
5–10°C conditions are unfavorable for the
development of early strength. These
effects will be most prevalent in thin
sections, in the near surface of larger
sections, and in concrete made with slow
hydrating cements. The bulk strength of
larger sections will be less affected
because, generally, the internal
temperature will be elevated by the heat of
hydration.
Effect of temperature
30. Curing Concrete
Concrete should not be allowed to freeze
before it has gained sufficient strength to
resist damage. According to ACI 308 this
strength is approximately 3.5 MPa. Air
entrained concrete should not be allowed to
undergo any freeze–thaw cycles until it has
reached a strength of approximately 25
MPa. Non air-entrained concrete should, of
course, never be allowed to undergo
freezing and thawing while saturated. The
temperature of concrete during curing
depends on:
Effect of temperature
31. Curing Concrete
• The dimensions of the element
• The weather (ambient conditions)
• cement type cement content
• Admixtures (accelerators, retarders)
• The fresh concrete temperature
• Formwork type/insulation
• Formwork stripping time
Mostly, temperature control of in-situ concrete
during hardening is only attempted at
temperature extremes where, for example,
there is:
• A risk of freezing
• A risk of an excessive peak temperature or
an excessive temperature difference across
the section.
Effect of temperature
32. Curing Concrete
The peak temperature in a section should
generally be kept below about 65–70°C to
minimize the effect on compressive
strength. Measures to reduce peak
temperatures are beyond the scope of
normal curing techniques and may include
cooling of the fresh concrete by various
means or cooling of the placed concrete by
means of cooling pipes within the section.
Effect of temperature
33. Curing Concrete
Concrete allowed to freeze before a certain
minimum degree of hardening has been
achieved will be permanently damaged by the
disruption from the expansion of the water
within the concrete as it freezes. This will
result in irretrievable strength loss.
Excessive evaporation from an exposed
horizontal surface within the first
approximately 24 hours after casting will result
in plastic shrinkage cracking and a weak,
dusty surface. An excessive temperature
difference through the cross-section of an
element will result in early thermal cracking
due to restraint to contraction of the cooling
outer layers from the warmer inner concrete.
What happens if concrete is not
cured properly?
34. Curing Concrete
Inadequate curing will result in the
properties of the surface layer of concrete,
up to 30–50 mm, not meeting the intentions
of the designer in terms of durability,
strength and abrasion resistance.
What happens if concrete is not
cured properly?
35. Curing Concrete
-The effect of curing on strength development
is limited to the near-surface of concrete so
its effect on strength will depend on the
element size and type of loading that will be
applied.
-The effect on large elements loaded in
compression will be much less than on
slender elements loaded in flexure. It is
unlikely that the structural capacity of most
elements would be significantly reduced by
poor curing.
The effect of curing on strength
36. Curing Concrete
-Required curing duration is sometimes
expressed in terms of the maturity of the
concrete.
-The maturity concept is used to predict the
rate of strength development at different
temperatures; it is mostly used for the
determination of formwork stripping time
and for structural considerations such as
time at loading.
The maturity concept for estimation
of required curing duration
37. Curing Concrete
-Maturity allows the strength of a concrete of
known temperature-time history to be
predicted from laboratory specimens cured
under standard conditions. The maturity is
the sum of the product of temperature
(above a datum level, usually –11°C, the
temperature at which hydration is said to
cease) and the time over which the
temperature prevails:
M = Σ (T ・ Δt) [°C.h]
The maturity concept for estimation
of required curing duration
38. Curing Concrete
Equal maturity should mean equal strength; but
the relationship between maturity and strength
depends on the actual cement type and
strength class used, the water/cement ratio
and whether any significant water loss occurs
during curing. The maturity concept cannot, at
the current state of knowledge, be directly
related to durability aspects rather than
strength. Thus where curing is required for
properties such as abrasion resistance,
permeability, freeze–thaw resistance, etc. it
may be necessary to extend curing beyond
the period predicted by maturity at which a
certain strength develops.
The maturity concept for estimation
of required curing duration
39. Curing Concrete
-Practical applications of accelerated curing
include:
1- Ensuring a daily cycle with, for example,
apartment formwork systems.
2 -Speeding construction in winter
conditions.
3 -Ensuring multiple daily use of moulds
used for precast concrete.
4 -Reducing the time between production
and delivery of precast concrete elements.
Applications of accelerated curing
40. Curing Concrete
1-Steam in pipes (precast technique
mainly).
2- Gas heating. This system is common for
in-situ construction.
3- Electric heating
4- Turbo heaters
Methods of accelerated curing
41. Curing Concrete
Accelerated curing has the following effects
on the properties of concrete:
1- Reduces the ultimate strength by up to 30
per cent depending on the peak temperature
reached.
2- A significant increase in coarse porosity
depending on the temperature reached.
3- If the curing temperature is high, there is a
significant risk of delayed ettringite formation.
4- For in-situ construction, accelerated curing
will increase the risk of early-age thermal
cracking caused by external restraint.
Effect of accelerated curing on
concrete properties
42. Curing Concrete
-The reason for the loss of strength and
increase in coarse porosity is believed to be
due to the hydration products forming close
to the original cement grains and not
spreading uniformly throughout the space
between the cement grains. If the peak
temperature during accelerated curing does
not exceed 65°C, the effect on long-term
properties is not significant.
Effect of accelerated curing on
concrete properties