This document summarizes the description and condition of a bridge located at Chemin Côte-des-Neiges and Chemin Remembrance in Montreal. The bridge is made of concrete and steel and is owned by the city. It shows signs of deterioration from corrosion, cracking, and efflorescence. Testing and evaluations indicate repairs are needed for corrosion, alkali-silica reaction, and cracks. Recommendations include repairs to the concrete and application of protective coatings or overlays. The bridge is rated as deficient but repairs are not urgent unless the planned elimination is delayed.
This document summarizes the first phase of training at the Central Engineering Workshop. It describes the various sections of the Bridge Engineering Department and their responsibilities, including drawing, templating, cutting, jig fabrication, welding, riveting, sawing, painting, and fabrication of plate girders. It provides examples of work done in each section and concludes with details on site visits to inspect bridges and recommended repairs.
Auber_Steel fiber reinforcement concrete_Slab on ground-Design NoteHoa Nguyen
This document provides design guidelines for slabs on ground using Auber steel fiber concrete. It discusses general principles of yield line design theory and describes procedures for determining the load carrying capacity of slabs. Material properties for Auber steel fibers are specified based on testing standards. The design process involves discretizing the slab cross-section into layers and determining fiber distribution. Load cases include uniform and point loads. Models are presented for analyzing the effects of temperature, shrinkage, and different load configurations. Critical aspects like shear capacity and punching are also addressed.
RESTORATION OF EXISTING MAJOR BRIDGE ACROSS RIVER BHADAR ON NATIONAL HIGHWAY ...IEI GSC
By S.K.Patel, P C Gandhi S R Shah J N Prajapati
at 31st National Convention of Civil Engineers
organised by
Gujarat State Center, The Institution of Engineers (India) at Ahmedabad
Lyapichev. Analysis, design & behavior of CFRDsYury Lyapichev
This document provides information on the analysis, design, behavior, and seismic resistance of concrete face rockfill dams (CFRDs). It discusses numerical modeling of CFRDs, stresses in the concrete face and underlying transition zones, and the effects of high compressibility of rockfill materials. It also summarizes general recommendations for dynamic analysis and design of high CFRDs in seismic regions, including use of roller compacted concrete to reduce concrete face deformation. A new design for the 275m high Kambarata-1 CFRD in Kyrgyzstan incorporates this technique to improve seismic safety.
The document discusses inspection and maintenance of reinforced concrete and steel bridges. It describes the importance of regular bridge inspection using various instrumentation to detect cracks, corrosion, and other issues. Bridges require maintenance to address damage over time from factors like weather, traffic loads, and corrosion. Common repairs include replacing expansion joints, repairing cracks, and addressing structural issues. Proper inspection and maintenance are needed to preserve bridge integrity and safety.
The document outlines the requirements and specifications for civil construction works under SP 1279 and reinforced concrete works under SP 1282. It includes requirements for excavation, backfilling, fencing, hard landscaping, graded roads, formwork, reinforcement, concrete mix design, sampling, placing, finishing, curing, protective coating, and grouting. Testing and documentation is required for materials, compaction, concrete cubes, and finishes to ensure compliance with specifications.
This document summarizes the first phase of training at the Central Engineering Workshop. It describes the various sections of the Bridge Engineering Department and their responsibilities, including drawing, templating, cutting, jig fabrication, welding, riveting, sawing, painting, and fabrication of plate girders. It provides examples of work done in each section and concludes with details on site visits to inspect bridges and recommended repairs.
Auber_Steel fiber reinforcement concrete_Slab on ground-Design NoteHoa Nguyen
This document provides design guidelines for slabs on ground using Auber steel fiber concrete. It discusses general principles of yield line design theory and describes procedures for determining the load carrying capacity of slabs. Material properties for Auber steel fibers are specified based on testing standards. The design process involves discretizing the slab cross-section into layers and determining fiber distribution. Load cases include uniform and point loads. Models are presented for analyzing the effects of temperature, shrinkage, and different load configurations. Critical aspects like shear capacity and punching are also addressed.
RESTORATION OF EXISTING MAJOR BRIDGE ACROSS RIVER BHADAR ON NATIONAL HIGHWAY ...IEI GSC
By S.K.Patel, P C Gandhi S R Shah J N Prajapati
at 31st National Convention of Civil Engineers
organised by
Gujarat State Center, The Institution of Engineers (India) at Ahmedabad
Lyapichev. Analysis, design & behavior of CFRDsYury Lyapichev
This document provides information on the analysis, design, behavior, and seismic resistance of concrete face rockfill dams (CFRDs). It discusses numerical modeling of CFRDs, stresses in the concrete face and underlying transition zones, and the effects of high compressibility of rockfill materials. It also summarizes general recommendations for dynamic analysis and design of high CFRDs in seismic regions, including use of roller compacted concrete to reduce concrete face deformation. A new design for the 275m high Kambarata-1 CFRD in Kyrgyzstan incorporates this technique to improve seismic safety.
The document discusses inspection and maintenance of reinforced concrete and steel bridges. It describes the importance of regular bridge inspection using various instrumentation to detect cracks, corrosion, and other issues. Bridges require maintenance to address damage over time from factors like weather, traffic loads, and corrosion. Common repairs include replacing expansion joints, repairing cracks, and addressing structural issues. Proper inspection and maintenance are needed to preserve bridge integrity and safety.
The document outlines the requirements and specifications for civil construction works under SP 1279 and reinforced concrete works under SP 1282. It includes requirements for excavation, backfilling, fencing, hard landscaping, graded roads, formwork, reinforcement, concrete mix design, sampling, placing, finishing, curing, protective coating, and grouting. Testing and documentation is required for materials, compaction, concrete cubes, and finishes to ensure compliance with specifications.
This document provides specifications for constructing sewer manholes, including materials, installation procedures, and testing requirements. Concrete, masonry units, and precast sections will be used for manhole structures. Joints must be sealed and waterproof coatings applied. Manholes will be tested for water exfiltration leakage according to specified standards. Not less than 20% of manholes shall undergo testing to ensure compliance.
This document discusses several special concreting techniques:
- Pumped concrete is concrete that can be pushed through a pipeline and must have a design that prevents blockages.
- Shortcrete or gunite is a mortar or fine concrete pneumatically projected at high velocity, used for thin sections with less formwork.
- Underwater concrete requires special mixes placed via bagging, buckets, tremie pipes, or grouted aggregates to prevent water intrusion.
- Other techniques include pre-packed concrete placed underwater and special considerations for hot/cold weather concreting. Proper mix design and placement methods are essential for successful implementation of special concreting applications.
The document discusses various technologies for underwater concrete construction, including concrete production from floating batch plants, concrete delivery via transit mixers and barges, and concrete placement using tremie methods. It covers topics like mix design, workability, placement procedures, quality control, and performance requirements. Case studies are presented on projects like dam and lock construction, coral reef repair, and canal lining replacement.
The document outlines a plan to abandon 10 wells in the Cold Lake Oil Sands Area. It provides details on the history and current status of each well, and whether they are compliant with AER directives on proper cementing and plugging procedures. For the non-compliant wells, it estimates the potential costs to remediate them with a waiver or without. In total, 4 wells are compliant and the estimated cost for all 10 wells is $102,000 with waivers, but would be $1,504,000 without any waivers granted.
1. The document provides a method statement for slope stabilization work for an excavated slope at a 10 MW hydroelectric power project site.
2. It describes installing soil nails and rock anchors into the slope, followed by wire mesh and shotcrete layers, to strengthen a cracked irrigation canal embankment and fractured rock slope.
3. Technical details, procedures, equipment, schedules and quantities are provided for installing the soil nails and rock anchors, applying the wire mesh and shotcrete layers, and completing the slope stabilization work over 50 days.
The document provides guidelines for designing shield tunnel linings, including:
- The guidelines were developed by the ITA Working Group from 1993-1999 to promote advances in shield tunnel design.
- Key aspects of shield tunnel lining design covered include deciding loads, material properties, structural analysis methods, safety checking, and construction details. Numerical modeling and analytical methods are recommended for analyzing member forces in the lining.
tunnelling scope, construction techniques and necessityShashank Gaurav
This document discusses tunnel construction methods and planning. It describes the main types of tunnels based on application and construction method. The key construction methods covered are cut-and-cover, pipe jacking, shield tunneling, New Austrian tunneling method, and immersed tube tunneling. For each method, the document outlines the construction sequence, advantages, and disadvantages. Proper planning stages including investigations and alignment selection are also emphasized.
This document discusses various repair options for concrete roadways including partial depth repairs, full depth repairs, dowel bar retrofit, cross stitching, diamond grinding, joint resealing, and concrete overlays. The techniques aim to restore the structure and ride quality of deteriorating concrete pavement through minimally disruptive rehabilitation methods.
Bridge rehabilitation covers many complex engineering problems and economic issues. It involves repairing, strengthening, or replacing existing bridges to improve their structural condition and functional capabilities. The main factors that can lead to bridge deterioration include inner bridge factors like design flaws; traffic load factors from increasing vehicle loads and speeds; weather and environmental factors such as pollution and temperature fluctuations; and inadequate maintenance. Bridge rehabilitation aims to address deterioration from these sources and extend the usable life of bridges.
Rockbolts and dowels are used to support underground excavations. Rockbolts are tensioned steel rods anchored with mechanical anchors or resin, while dowels are untensioned steel bars grouted into rock. Different support methods are used depending on rock mass properties and stress levels, ranging from spot bolts to heavy bolting patterns with mesh and shotcrete. Mechanically anchored rockbolts work via expansion shells, while resin-anchored bolts provide stronger anchoring, especially in weak rock. Hollow core bolts and resin grouting provide more reliable permanent support by filling the annular space to prevent corrosion.
This presentation was given as part of a site visit to the Kwun Tong line extension in Hong Kong on the morning of Saturday 25th October 2014. The visit was organised between the APM HK branch and the Nishimatsu Construction Company ltd.
This was an opportunity to see the progress of the Kwun Tong Line Extension (KTE).
The current railway network has not covered some of the more densely populated areas such as Ho Man Tin, Hung Hom and Whampoa. Additionally, the frequent traffic jams from the Cross Harbour Tunnel during peak hours cause great inconvenience to commuters.
The Mass Transit Railway (MTR) Corporation has long been planning to launch the Kwun Tong Line Extension project (KTE) to alleviate the serious traffic congestion. MTR was authorised to proceed with the project in 2010 and the construction of the new rail line commenced in 2011.
The alignment of KTE will be extended from the existing Yau Ma Tei Station to Whampoa via Ho Man Tin with 2 new stations to be built.
The contract of construction of the new Ho Man Tin Station and a tunnel from Yau Ma Tei to Whampoa was awarded to Nishimatsu Construction Company Limited. Meanwhile the Chun Wo – Hip Hing joint venture is in charge of the construction contract for Whampoa Station and overrun tunnel. The project is currently underway at a cost of around HK$5.3 billion (in December 2009 prices).
This site visit will take you to see the Ho Man Tin Station construction work, followed by the Yau Ma Tei to Whampoa Tunnel, HMT Station cavern and a general view of the tunnelling and station (which has been formed within the cavern area) works.
Lining is an integral part of Tunneling. Once the Shotcrete line ,i.e the B-line,is laid, the Kerb/Kicker or Say Beam is executed. Next Comes the Geotextile/Waterproofing Membrane. After that, C-line is laid which is referred to as inner lining.
Soil Nails Reinforcement - Design nails soil stabilization --مسامير قضبان تسل...Dr.Youssef Hammida
تثبيت وتسليح - تربة الجدران - الساندة بالمسامير
تستخدم تقنية المسامير في تثبيت المنحدرات الترابية والجدران الاستنادية والأنفاق الى تدعيم حفريات التأسيس العميقة. وتتلخص الطريقة في غرز قضبان معدنية طويلة ذات المقطع الصغيرامام المنحدر المراد تدعيمه بحيث تخترق هذه القضبان كتلة التربة إلى مسافة ونباعدات محددة مثبتة في منطقة خارج مخروط الانهيار حيث يؤمن استقرار سطح التربة على وجه المنحدر بطبقة تغطية رقيقة من الحجر او الخرسانة المقذوفة مسلحة بشبكة معدمية إنشائية مهمتها حجز التربة بين المسامير ويثبت المسمار نفسه على طبقة البيتون المقذوف بصفيحة تثبيت معدنية مربعة الشكل
Soil nail wall - Soil nailing - soil nailing walls
Soil nailing is an earth retention technique using grouted tension-resisting steel elements (nails) that can be design for permanent or temporary support. The walls are generally constructed from the top down. Typically, 3 to 6 feet of soil is excavated from the top of the planned excavation. Near-horizontal holes are drilled into the exposed face at typically 3 to 6 foot centers. Tension-resisting steel bars are inserted into the holes and grouted. A drainage system is installed on the exposed face, followed by the application of reinforced shotcrete facing. Precast face
NATM (New Austrian Tunneling Method ) in TunnelingHamed Zarei
1. NATM (New Austrian Tunneling Method) is a flexible tunneling method that utilizes shotcrete, wire mesh, rock bolts, and lattice girders for tunnel support. It mobilizes the strength of the rock mass and uses dynamic design that adapts the support based on rock conditions.
2. Excavation in NATM progresses from top heading to benches in poor rock. It is done in small sequential cells to support unstable ground. Primary lining of shotcrete is applied immediately after excavation.
3. Rock mass is classified using methods like RQD, RMR, and Q-factor to determine appropriate support. Flexible shotcrete and bolting allow adaptation to changing geology encountered during tunnel
The document summarizes a case study of two projects to install structural linings in oviform sewers for Sydney Water Corporation. For one project, an 18mm thick lining was installed in a 13m deep, 350m long oviform sewer under a busy road. This was one of the most difficult CIPP linings installed in Australia due to its thickness and single length. The second project involved concrete encasement of a deteriorated bend in addition to CIPP lining. Both projects required complex planning and execution, including sewer bypass and traffic control.
The document provides design details for foundations and retaining walls for a conveyor system and storage area at Suez Cement Company. General design notes specify the design standards, loads, foundation conditions, and material specifications to be used. Foundations are designed for individual conveyor components using Excel, MathCAD, and SAP2000 for analysis and reinforcement detailing. Retaining wall and strap footing design is conducted in SAP2000, applying earth pressures, uniform loads, and determining moments and reinforcement. Design drawings including plans, sections and reinforcement details are provided.
This document discusses different types of rock bolts used in underground mining excavations. It describes mechanically anchored, grouted anchor, and frictional anchor bolts. Mechanically anchored bolts use an expansion shell or resin to anchor into the rock. Grouted anchor bolts are inserted into a borehole and cemented in place with resin or cement. Frictional bolts like split sets are forced into an undersized hole to provide support. The document also outlines the unconfined compression test procedure used to evaluate rock strength in a laboratory.
This document discusses silo design and failures. It covers:
- Causes of silo failures including design errors like not accounting for eccentric flow channels, construction errors, changes in silo usage, and lack of maintenance.
- Types of silo loads including initial fill loads when first filling and flow-induced loads that develop after material withdrawal begins.
- Procedures for calculating initial fill loads on silo cylinders for off-center filling conditions and along ridges. Flow-induced loads are generally more critical for structural design.
The underwater concreting techniques designed mostly to prevent cement washout. These methods did not obtain the full purpose of avoiding cement wash out at early stages of using under water concreting apart from cases where large masses of concreting were employed.
Este documento presenta una actividad didáctica para preescolares con el objetivo de fortalecer la implementación de proyectos de aula a través de un tema sobre los miedos de los niños. La actividad consta de dos momentos: en el primero, los niños dibujan un monstruo que representa sus temores, y en el segundo, pintan y crean una figura de su monstruo para hablar sobre lo que les daba miedo. El propósito es ayudar a los niños a identificar y enfrentar sus emociones de manera positiva
This document provides specifications for constructing sewer manholes, including materials, installation procedures, and testing requirements. Concrete, masonry units, and precast sections will be used for manhole structures. Joints must be sealed and waterproof coatings applied. Manholes will be tested for water exfiltration leakage according to specified standards. Not less than 20% of manholes shall undergo testing to ensure compliance.
This document discusses several special concreting techniques:
- Pumped concrete is concrete that can be pushed through a pipeline and must have a design that prevents blockages.
- Shortcrete or gunite is a mortar or fine concrete pneumatically projected at high velocity, used for thin sections with less formwork.
- Underwater concrete requires special mixes placed via bagging, buckets, tremie pipes, or grouted aggregates to prevent water intrusion.
- Other techniques include pre-packed concrete placed underwater and special considerations for hot/cold weather concreting. Proper mix design and placement methods are essential for successful implementation of special concreting applications.
The document discusses various technologies for underwater concrete construction, including concrete production from floating batch plants, concrete delivery via transit mixers and barges, and concrete placement using tremie methods. It covers topics like mix design, workability, placement procedures, quality control, and performance requirements. Case studies are presented on projects like dam and lock construction, coral reef repair, and canal lining replacement.
The document outlines a plan to abandon 10 wells in the Cold Lake Oil Sands Area. It provides details on the history and current status of each well, and whether they are compliant with AER directives on proper cementing and plugging procedures. For the non-compliant wells, it estimates the potential costs to remediate them with a waiver or without. In total, 4 wells are compliant and the estimated cost for all 10 wells is $102,000 with waivers, but would be $1,504,000 without any waivers granted.
1. The document provides a method statement for slope stabilization work for an excavated slope at a 10 MW hydroelectric power project site.
2. It describes installing soil nails and rock anchors into the slope, followed by wire mesh and shotcrete layers, to strengthen a cracked irrigation canal embankment and fractured rock slope.
3. Technical details, procedures, equipment, schedules and quantities are provided for installing the soil nails and rock anchors, applying the wire mesh and shotcrete layers, and completing the slope stabilization work over 50 days.
The document provides guidelines for designing shield tunnel linings, including:
- The guidelines were developed by the ITA Working Group from 1993-1999 to promote advances in shield tunnel design.
- Key aspects of shield tunnel lining design covered include deciding loads, material properties, structural analysis methods, safety checking, and construction details. Numerical modeling and analytical methods are recommended for analyzing member forces in the lining.
tunnelling scope, construction techniques and necessityShashank Gaurav
This document discusses tunnel construction methods and planning. It describes the main types of tunnels based on application and construction method. The key construction methods covered are cut-and-cover, pipe jacking, shield tunneling, New Austrian tunneling method, and immersed tube tunneling. For each method, the document outlines the construction sequence, advantages, and disadvantages. Proper planning stages including investigations and alignment selection are also emphasized.
This document discusses various repair options for concrete roadways including partial depth repairs, full depth repairs, dowel bar retrofit, cross stitching, diamond grinding, joint resealing, and concrete overlays. The techniques aim to restore the structure and ride quality of deteriorating concrete pavement through minimally disruptive rehabilitation methods.
Bridge rehabilitation covers many complex engineering problems and economic issues. It involves repairing, strengthening, or replacing existing bridges to improve their structural condition and functional capabilities. The main factors that can lead to bridge deterioration include inner bridge factors like design flaws; traffic load factors from increasing vehicle loads and speeds; weather and environmental factors such as pollution and temperature fluctuations; and inadequate maintenance. Bridge rehabilitation aims to address deterioration from these sources and extend the usable life of bridges.
Rockbolts and dowels are used to support underground excavations. Rockbolts are tensioned steel rods anchored with mechanical anchors or resin, while dowels are untensioned steel bars grouted into rock. Different support methods are used depending on rock mass properties and stress levels, ranging from spot bolts to heavy bolting patterns with mesh and shotcrete. Mechanically anchored rockbolts work via expansion shells, while resin-anchored bolts provide stronger anchoring, especially in weak rock. Hollow core bolts and resin grouting provide more reliable permanent support by filling the annular space to prevent corrosion.
This presentation was given as part of a site visit to the Kwun Tong line extension in Hong Kong on the morning of Saturday 25th October 2014. The visit was organised between the APM HK branch and the Nishimatsu Construction Company ltd.
This was an opportunity to see the progress of the Kwun Tong Line Extension (KTE).
The current railway network has not covered some of the more densely populated areas such as Ho Man Tin, Hung Hom and Whampoa. Additionally, the frequent traffic jams from the Cross Harbour Tunnel during peak hours cause great inconvenience to commuters.
The Mass Transit Railway (MTR) Corporation has long been planning to launch the Kwun Tong Line Extension project (KTE) to alleviate the serious traffic congestion. MTR was authorised to proceed with the project in 2010 and the construction of the new rail line commenced in 2011.
The alignment of KTE will be extended from the existing Yau Ma Tei Station to Whampoa via Ho Man Tin with 2 new stations to be built.
The contract of construction of the new Ho Man Tin Station and a tunnel from Yau Ma Tei to Whampoa was awarded to Nishimatsu Construction Company Limited. Meanwhile the Chun Wo – Hip Hing joint venture is in charge of the construction contract for Whampoa Station and overrun tunnel. The project is currently underway at a cost of around HK$5.3 billion (in December 2009 prices).
This site visit will take you to see the Ho Man Tin Station construction work, followed by the Yau Ma Tei to Whampoa Tunnel, HMT Station cavern and a general view of the tunnelling and station (which has been formed within the cavern area) works.
Lining is an integral part of Tunneling. Once the Shotcrete line ,i.e the B-line,is laid, the Kerb/Kicker or Say Beam is executed. Next Comes the Geotextile/Waterproofing Membrane. After that, C-line is laid which is referred to as inner lining.
Soil Nails Reinforcement - Design nails soil stabilization --مسامير قضبان تسل...Dr.Youssef Hammida
تثبيت وتسليح - تربة الجدران - الساندة بالمسامير
تستخدم تقنية المسامير في تثبيت المنحدرات الترابية والجدران الاستنادية والأنفاق الى تدعيم حفريات التأسيس العميقة. وتتلخص الطريقة في غرز قضبان معدنية طويلة ذات المقطع الصغيرامام المنحدر المراد تدعيمه بحيث تخترق هذه القضبان كتلة التربة إلى مسافة ونباعدات محددة مثبتة في منطقة خارج مخروط الانهيار حيث يؤمن استقرار سطح التربة على وجه المنحدر بطبقة تغطية رقيقة من الحجر او الخرسانة المقذوفة مسلحة بشبكة معدمية إنشائية مهمتها حجز التربة بين المسامير ويثبت المسمار نفسه على طبقة البيتون المقذوف بصفيحة تثبيت معدنية مربعة الشكل
Soil nail wall - Soil nailing - soil nailing walls
Soil nailing is an earth retention technique using grouted tension-resisting steel elements (nails) that can be design for permanent or temporary support. The walls are generally constructed from the top down. Typically, 3 to 6 feet of soil is excavated from the top of the planned excavation. Near-horizontal holes are drilled into the exposed face at typically 3 to 6 foot centers. Tension-resisting steel bars are inserted into the holes and grouted. A drainage system is installed on the exposed face, followed by the application of reinforced shotcrete facing. Precast face
NATM (New Austrian Tunneling Method ) in TunnelingHamed Zarei
1. NATM (New Austrian Tunneling Method) is a flexible tunneling method that utilizes shotcrete, wire mesh, rock bolts, and lattice girders for tunnel support. It mobilizes the strength of the rock mass and uses dynamic design that adapts the support based on rock conditions.
2. Excavation in NATM progresses from top heading to benches in poor rock. It is done in small sequential cells to support unstable ground. Primary lining of shotcrete is applied immediately after excavation.
3. Rock mass is classified using methods like RQD, RMR, and Q-factor to determine appropriate support. Flexible shotcrete and bolting allow adaptation to changing geology encountered during tunnel
The document summarizes a case study of two projects to install structural linings in oviform sewers for Sydney Water Corporation. For one project, an 18mm thick lining was installed in a 13m deep, 350m long oviform sewer under a busy road. This was one of the most difficult CIPP linings installed in Australia due to its thickness and single length. The second project involved concrete encasement of a deteriorated bend in addition to CIPP lining. Both projects required complex planning and execution, including sewer bypass and traffic control.
The document provides design details for foundations and retaining walls for a conveyor system and storage area at Suez Cement Company. General design notes specify the design standards, loads, foundation conditions, and material specifications to be used. Foundations are designed for individual conveyor components using Excel, MathCAD, and SAP2000 for analysis and reinforcement detailing. Retaining wall and strap footing design is conducted in SAP2000, applying earth pressures, uniform loads, and determining moments and reinforcement. Design drawings including plans, sections and reinforcement details are provided.
This document discusses different types of rock bolts used in underground mining excavations. It describes mechanically anchored, grouted anchor, and frictional anchor bolts. Mechanically anchored bolts use an expansion shell or resin to anchor into the rock. Grouted anchor bolts are inserted into a borehole and cemented in place with resin or cement. Frictional bolts like split sets are forced into an undersized hole to provide support. The document also outlines the unconfined compression test procedure used to evaluate rock strength in a laboratory.
This document discusses silo design and failures. It covers:
- Causes of silo failures including design errors like not accounting for eccentric flow channels, construction errors, changes in silo usage, and lack of maintenance.
- Types of silo loads including initial fill loads when first filling and flow-induced loads that develop after material withdrawal begins.
- Procedures for calculating initial fill loads on silo cylinders for off-center filling conditions and along ridges. Flow-induced loads are generally more critical for structural design.
The underwater concreting techniques designed mostly to prevent cement washout. These methods did not obtain the full purpose of avoiding cement wash out at early stages of using under water concreting apart from cases where large masses of concreting were employed.
Este documento presenta una actividad didáctica para preescolares con el objetivo de fortalecer la implementación de proyectos de aula a través de un tema sobre los miedos de los niños. La actividad consta de dos momentos: en el primero, los niños dibujan un monstruo que representa sus temores, y en el segundo, pintan y crean una figura de su monstruo para hablar sobre lo que les daba miedo. El propósito es ayudar a los niños a identificar y enfrentar sus emociones de manera positiva
En el aula taller, tanto los docentes como los alumnos aprenden y juegan un rol activo. Los alumnos se motivan a participar en las actividades grupales e individuales, aprendiendo habilidades sociales y de trabajo en equipo. El docente deja de ser el único proveedor de información para pasar a guiar el aprendizaje de los alumnos, observando y evaluando su progreso.
O documento discute programas de financiamento habitacional para áreas rurais oferecidos pelo governo federal, incluindo o Programa Carta de Crédito FGTS, o Programa Crédito Solidário e o Programa de Subsídio à Habitação de Interesse Social. Ele explica os objetivos, recursos, critérios de elegibilidade e modalidades de cada programa para ajudar agricultores familiares a construírem ou reformarem suas casas.
La empresa tiene como misión ofrecer la mejor calidad de zapatos en el país y ser reconocida a nivel nacional por su calidad y servicio. Su visión es convertirse en la empresa de calzado fino más grande del país para el 2017 y posicionarse como la mejor en calidad y diseño. Sus objetivos incluyen proporcionar información de la empresa de forma continua y ordenada, así como atender al cliente y tomar decisiones autónomas para alcanzar sus metas.
SlideShare es un sitio web que permite a los usuarios subir y compartir presentaciones de diapositivas, documentos, PDF y portafolios. Fue lanzado en 2006 y adquirido por LinkedIn en 2012. Los usuarios pueden crear una cuenta gratis, subir archivos y compartirlos de manera pública o privada. El sitio tiene más de 70 millones de usuarios activos mensuales.
Janneth Patricia Romo Guacas es una licenciada en Filosofía y Letras que ha trabajado como docente en el sector privado y público en Colombia. Actualmente enseña Lengua Castellana en la Institución Educativa José Antonio Galán y también forma parte del grupo de Tutores Pedagógicos de Nariño. Disfruta de la escritura y la danza, y ve su nuevo rol como tutora como una oportunidad para compartir conocimientos y enriquecer las experiencias de enseñanza y aprendizaje.
La gestión de proyectos consiste en organizar y administrar los recursos de un proyecto para completarlo dentro del tiempo, costo y alcance planificados, requiriendo un director o equipo de dirección firme, organización y planificación estratégica, asignación de roles y recursos, y el cumplimiento de las fases del ciclo de vida del proyecto con sus entregables correspondientes. Para lograr esto con éxito, se necesita un perfil de responsables que sean profesionales idóneos, capaces de gestionar, coordinar y controlar
El documento habla sobre las posibilidades ilimitadas que tenemos y que nuestros límites los ponemos nosotros mismos. Al enfocarnos en nuestras habilidades en lugar de nuestras limitaciones, podemos lograr grandes cosas y acercarnos a un mundo lleno de oportunidades.
El documento describe la importancia del juego en el desarrollo infantil. El juego es una actividad placentera y espontánea que favorece el desarrollo social, la creatividad y la adaptación del niño al mundo. A través del juego, los niños aprenden habilidades importantes como la resolución de problemas y la comunicación. El juego también beneficia el desarrollo cognitivo al enriquecer la imaginación y desarrollar habilidades como la atención y la memoria.
This document lists the names of 17 students in the 4a I.A.G class for the 2012-2013 school year. The names include Bario Gondola, Ignacio Chambers Sanchez, Jesus Condori Huamari, Carolayth Diaz Rubio, Laura Garcia Arollo, Lourdes Ionescu, Alex Gonzalez Garcia, Andrea Ortega Palacios, Alejandro Ponce Montalvan, Andrea Rodrigez, Valentin Paguyo, Jonaly Marin, Saray Anamisi Romero, Josselyn Lin, and Xuan Lin.
El documento describe los conceptos clave de la gerencia de proyectos de tecnología educativa. Explica que la gerencia de proyectos implica un esfuerzo temporal para crear un producto único mediante fases como la iniciación, planificación, ejecución, seguimiento y control, y cierre. También identifica a los responsables clave de un proyecto y los conocimientos y habilidades necesarios de un director de proyectos.
The document discusses creating and sharing presentations online. It introduces Prezi as a tool for creating interactive presentations using zooming and motion. It describes how presentations can be uploaded to SlideShare, an online sharing site, and embedded on web pages or linked. Finally, it discusses VoiceThread, where presentations can be shared and users can add asynchronous comments.
El documento proporciona seis pasos para lograr una presentación efectiva: 1) comience con claridad sobre el tema principal sin rodeos; 2) sea informativo en lugar de aburrido al proporcionar información útil; 3) prepare una visión general organizada de la presentación con gráficos y animaciones; 4) practique la presentación como un actor con claridad, tiempo y postura; 5) realice la presentación de manera clara y comprensible con el volumen adecuado y evitando muletillas; 6) tenga un plan de respaldo por si
Este documento describe un prototipo de teléfono que combina el diseño retro de los años 80 con rueda giratoria para marcar números y la última tecnología, ofreciendo un toque elegante para el hogar u oficina. También menciona que Nokia lanzó un sitio web que muestra las futuras tecnologías que planea incorporar gradualmente en sus teléfonos móviles para dar una visión de cómo será el mundo tecnológico en el futuro.
The document introduces the D&B Valued Service Method (VSM), which helps service-oriented organizations transform from creating satisfied customer experiences to creating valued experiences. VSM was developed based on research of over 50,000 service cases and customer surveys of over 100 retail brands. It provides a blueprint for strategy development, front-line execution, and tools for managers to understand key concepts and apply them to their work. VSM aims to enhance loyal customers, strengthen emotional attachment between organizations and customers, and maintain sustainable business growth through increased repurchase frequency and amount. It involves strategies, tools and content for senior management, middle management, and frontline staff.
Gerencia de proyectos de tecnología educativaanny muñoz
Este documento describe los conceptos clave de la gerencia de proyectos de tecnología educativa. Explica que el rol principal del gerente de proyectos es organizar y administrar los recursos para completar el proyecto dentro del alcance, tiempo y costo planificado. También detalla que los elementos que garantizan el ciclo de vida de un proyecto son el trabajo a realizar en cada fase, el tiempo de entrega de cada fase y los responsables involucrados. Por último, señala que los responsables de establecer el ciclo de vida de un proyect
Inspection,Repair and Strengthening of PSC Bridge.Mohammad Furqan
The document provides information on inspection, repair, and strengthening of pre-stressed concrete (PSC) bridges. It discusses common types of deterioration in concrete bridges such as carbonation, chloride attack, alkali-silica reaction, and corrosion of steel reinforcement. It outlines the inspection process including planning, objectives, equipment used, and what elements to inspect such as cracks, bearings, and prestressing components. Non-destructive testing methods like rebound hammer, ultrasonic pulse velocity, and cover meter tests are described. Finally, common repair methods for concrete like mortar filling, grouting, shotcrete, and fiber reinforced polymer wrapping are presented.
The document summarizes an inspection report of an underground tunnel structure in Montreal. It describes the major structural components, materials used, current conditions, deterioration over time, recommendations from previous inspections, and suggested repair and testing methods. The structure is in critical condition with extensive cracking, corrosion and rebar exposure. Immediate attention is needed on retaining walls, ceiling cracks and rebar corrosion. Non-destructive and destructive testing is recommended to further evaluate the deterioration and inform repair methods. Annual inspections should continue to monitor the condition.
IRJET- The Rehabilitation Techniques for Irwin BridgeIRJET Journal
This document discusses rehabilitation techniques for the Irwin Bridge, a masonry arch bridge in Sangli, India built in 1929. It has conducted a condition survey to detect damages and proposes various techniques to address issues found with the bridge's piers, abutments, deck slabs, river banks, and galleries. Rehabilitation techniques discussed include cellular foamed cement grouting for piers, replacing damaged stones and adding concrete mortar in abutments, removing unsound concrete and adding new patches in deck slabs, installing guide banks and other river training structures, and reconstructing severely damaged galleries. The conclusion emphasizes the importance of regular maintenance and using conservation-focused repair techniques to successfully rehabilitate historic masonry bridges
Uses of special kind of technologies for implementation of special kind of st...Rajesh Prasad
The said technical paper was presented by Rajesh Prasad in IC TRAM 2018 (International Conference- Technological Advancement in Railways and Metro Projects at Manekshaw Centre New Delhi on 04.10.2018
Your Score 1420Not bad. Your score means youre slightly bette.docxodiliagilby
Your Score: 14/20
Not bad. Your score means you're slightly better than the average at reading expressions. And research suggests that people can improve their emotion recognition skills with practice. So keep an eye out for our forthcoming empathy training tool, designed to boost your emotional intelligence. Sign upfor our e-newsletter for updates on it.
Drilling Engineering
Class 8
1
Casing
• What is casing?
• Pipe that is API certified for its specific application
• Why is casing set?
• Zonal Isolation when cemented in place
• Casing point selection
• Regulations
• Area Geology
• Formation Pressures
• As the operator, who decides on casing points?
2
Casing
• API casing is available in standard sizes from 4-1/2” to 20” OD
• Usually steel but can be aluminum, fiberglass, stainless steel,
plastic, titanium etc.
• One piece of casing pipe is referred to as a “joint” of casing
• Casing length is dependent on the “range” of pipe
• Range-1: 18-22ft
• Range-2: 27-30ft
• Range-3: 38-45ft
• Casing Threads are defined by the coupling type
• API Threads
• LTC: Long thread coupling
• STC: Short thread coupling
• BTC: Buttress thread coupling
• Semi & Premium Threads
• See VAM Presentation
3
Casing
• Casing Components
• Casing
• Size, Weight, Grade, Threads
• 9-5/8" 53.5# P-110 LTC Rg 3
• See Casing Data Chart
• What is Drift Diameter?
• Pup Joints
• Float Collars
• Float Shoe
• Guide Shoe
• Centralizers
• Baskets
• Scratchers/Scrapers
4
Casing
• Running Casing
• Bales/Elevators
• Power Tongs
• Torque Turn
• Calculate weight and Hookload HL
• Calculate collapse, how often should you fill the pipe?
• Is the pipe taking the proper amount of fluid to fill? CSGcap
• Is the proper amount of fluid coming back to the pits as the
casing is run in the hole? CSGcap & CSGdisp
• Once casing is landed, circulated mud. Calculate B/U
5
Casing
• Centralization
• Vertical Wells
• Never truly vertical, usually spiral
• Typically use bow spring type centralizers
• There are state regulations on centralizer placement
• The shoe is very important to be centralized
• Horizontal Wells
• Balance between too many and not enough centralizers
• Many types: rigid, floating, bow spring, bladed, spiral bladed, etc.
• Centralizer design software can model the well as drilled and suggest
centralizer placement
• High dogleg areas need more frequent centralizers to obtain
sufficient standoff
6
Casing
• Stand-off
• Pipe Stand-off is a major contributor to hole cleaning, mud
removal, and cement quality.
• % 𝑆𝑡𝑎𝑛𝑑𝑜𝑓𝑓 = ൗ𝑊𝑛 𝑅2−𝑅1 ∗ 100%
7
Casing
• Stand-off
• The Stand-off formula results a percentage, where 0% represents
the pipe in contact with the wellbore wall. 100% represents the
pipe is perfectly centered in the well.
• When the pipe is not centered, the wider portions will promote
flow due to less resistance. There can be pockets of cuttings or
mud in the tighter areas causing
Pt slab design philosophy with slides and pictures showing benefitPerwez Ahmad
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This document discusses ACI 301-5, which defines standard practices for structural concrete and concrete surface imperfections. It provides 13 definitions of common concrete defects, including plastic cracking, honeycombing, delamination, crazing, efflorescence, curling, bug holes, pop outs, alkali-silica reaction, dusting, concrete blisters, scaling, and blowup. It explains the causes and characteristics of each defect.
Structural and stability assessment for ex-pit dump toe (final)John Latilla
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This document discusses the importance of maintaining bridges through regular inspections and repairs. It outlines the necessary qualifications of inspection personnel and describes different categories and methods of bridge inspections. Key areas of focus include structural components, foundations, and approaches. The document emphasizes the need for thorough documentation of bridge conditions and history to facilitate maintenance and guide repair decisions. Regular inspections are necessary to catch small defects early and ensure public safety by preventing structural deterioration.
PDL’s Construction Development (Technical) Training Session-I_Structural.pptxChristopherThomas578171
This document provides an overview of structural construction materials and processes. It discusses aggregates, cement, water, reinforcement, admixtures, workability testing, water-cement ratios, concrete curing, embedded pipes, and cement and rebar storage. Formwork and scaffolding requirements are also outlined. Test procedures like slump tests and concrete cylinder tests are described. Typical reinforced concrete details are shown regarding clear cover, beam-column joints, splices and more.
The document discusses storage tank inspections and provides details on:
- Inspection techniques used to evaluate tank floors, shells, roofs, and structures. Inspections include engineering calculations per industry standards.
- Common materials used in tank construction like carbon steel, low-chrome alloys, and stainless steel. Corrosion allowances are also discussed.
- Types of inspections like routine in-service, external, and internal inspections. Factors that determine inspection intervals are outlined.
Civil Works Site Construction Guidelines for Haris & Co Civil Team.pdfusamazahoor159
Thrilled to unveil the culmination of my efforts: a comprehensive set of CME guidelines meticulously tailored for on-site telecom projects. These guidelines reflect not only my expertise but also my commitment to simplifying complexities and optimizing processes in the telecom sector. Dive into the details and let's elevate our practices together!
This document discusses techniques for repairing, rehabilitating, and retrofitting structures. It covers strengthening structural elements, repairing structures damaged by corrosion, fire, leakage, or earthquakes. Specific techniques addressed include repairing fire-damaged concrete, sealing leaks, repairing cracks, jacketing structural members, and dry packing. The document also covers engineered demolition methods like mechanical demolition, implosion, and deconstruction for taking down structures.
Protecting Occupied Buildings from Process Tank Rupture SpillageAdvisian
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Maintenance & repair of steel bridgesnaveen kumar
This document discusses the inspection and maintenance of steel bridges. It outlines the various components that should be inspected such as bearings, rivets, camber, and superstructure. Critical locations prone to issues like corrosion, fatigue cracks, and loose rivets are identified. The schedule and process for inspections by different roles is provided. Recommendations for maintenance activities like painting, epoxy coating, and metallizing of steel components are described.
This document summarizes the construction of rigid pavements. Rigid pavements use plain cement concrete slabs with dowel bars at joints for load transfer. They are used in areas with adverse conditions like heavy rainfall, poor soil/drainage, or extreme climate. Materials include cement, coarse and fine aggregates, and water. Construction involves subgrade preparation, forming slabs with joints, curing, and allowing time before opening to traffic. Joints include longitudinal, contraction, and expansion joints with filler and dowel bars to allow for expansion/contraction. Reinforcement improves strength and load distribution. Advantages include durability and low maintenance, while disadvantages include higher initial costs and traffic disruption during repairs.
This document discusses the importance of bridge maintenance, rehabilitation, and repair. It begins by defining a bridge and providing examples of important bridges in India. It then covers topics like bridge inspection procedures, common causes of bridge deterioration over time, and different maintenance and repair techniques. Regular inspection and timely repair or replacement of bridges is necessary for safety reasons, as bridge failures can lead to loss of life and disrupt transportation. Proper maintenance plays a vital role in ensuring bridges continue serving their important purpose of transportation.
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 document discusses repair and rehabilitation of concrete structures. It covers causes of distress in concrete structures such as structural issues, design/construction errors, chemical reactions, and corrosion of reinforcement. It then describes evaluation procedures for repair projects, including visual inspection, non-destructive testing, and core extraction/testing. Specific causes of cracks in concrete like plastic shrinkage, thermal stresses, and inadequate reinforcement are also outlined. Finally, routing and sealing of cracks is discussed as a common remedial repair technique.
2. Description of bridge
• Location of the bridge:
Chemin Côte-des-Neiges(North)/Chemin Remembrance(West)
3. Description of bridge
• Ownership of infrastructure:
It is under municipal ownership and jurisdiction of the City of
Montreal.
• Function:
It is used as a link between the downtown area and residential
areas such as Cote des Neiges and Mont-Royal while also
providing access for a return road under the bridge.
4. Description of bridge
• Bridge composed of:
oMajor Structural Components:
Concrete: Beams, columns, foundations, bridge deck
Steel: Reinforcing bars, stirrups, ties
oMinor Structural Components:
Steel railings, concrete barriers, asphalt on the bridge
deck
5. DESCRIPTION OF PERFORMANCE
AND LOADING CRITERIA
• Usage of the
Structure:
oThe bridge contains 3
lanes of one-way traffic
with no apparent
congestion.
oOverloaded trucks are
prohibited.
oNo sidewalk for
pedestrians.
6. DESCRIPTION OF PERFORMANCE
AND LOADING CRITERIA
• The structure is exposed to the following
conditions:
o De-icing salts
o Car exhaust, although it might not be severe, as there were
no apparent traffic congestion on or below the bridge.
o Retaining walls, column bases and supports all are in contact
with soil & groundwater. No obvious drainage system is
present.
7. DISCUSSION OF PRELIMINARY
FINDINGS
• The main cause of deterioration in the bridge appears to be
corrosion. It is evident all along the bridge deck and most of
the columns due to spalling of the concrete cover and rust
staining.
9. DISCUSSION OF PRELIMINARY
FINDINGS
• Rust and efflorescence of salt are apparent on the side and
under the bridge deck as reddish/orange and white stains
respectively.
11. RECOMMENDATIONS CONCERNING
FUTURE ACTIONS
• According to the records of la Ville de
Montreal, the deterioration rating is 68, hence
it is in a “Deficient” state.
• A plan to eliminate the overpass is in place.
However, if this does not happen before 2015,
repairs will be done to the overpass.
12. RECOMMENDATIONS CONCERNING
FUTURE ACTIONS
• Since the bridge is in deficient state and not a
critical one, no immediate action is required
even though the overpass is severely
damaged.
• If however repairs are done today, they would
cost less than as planned in 2015 since
deterioration due to corrosion and sulfate
attacks would increase exponentially with
time.
20. Structural/loading factors which may
increase/diminish the risk
• Dynamic loading
• Fatigue loads
• High permanent snow load
• Heavy dynamic natural loads
21. Testing for Corrosion
Short-Pulse Radar:
Will be used to detect the reinforcing steel locations
Will also detect delamination in the bridge deck.
One of the only available methods that works through asphalt overlays.
Rolling Pachometer:
Will be used to find the location of the reinforcing steel and compared
with the results of the short-pulse radar to achieve higher accuracy.
The rate of deterioration of the bars can be found in terms of a reduction
of its relative size.
A damage map can then be created and analyzed.
22. Testing for Efflorescence & ASR
Lab Test of Effloresced Solid:
A sample of the effloresced solid will be tested in the lab to
determine its composition.
UV Fluorescence technique for ASR:
This is a destructive test.
A solution of uranyl acetate solution is sprayed
on a fresh fracture surface.
A viewing box that emits UV light is used to
detect the affected regions.
This technique is fast, easy and accurate.
Will be used on bridge deck and rail end.
23. Testing for Carbonation
Phenolphthalein Test:
Will be used to determine the rate of
Carbonation.
A fractured surface will be sprayed with
phenolphthalein turning the concrete
pink, and carbonated areas will remain
unchanged.
If carbonation is found to be extensive, a core can be taken
along with chemical profiling to find the “depth of
carbonation”.
It is fast, cheap and reliable.
Will be tested mainly on the columns
24. Test for Transport Properties
The ISAT will be used to analyze transport properties as
it is not affected by carbonation and chloride content.
Initial Surface Absorbtion Test (ISAT):
It’s a semi-destructive technique
Field concrete must have been exposed to at least 48
hours of ambient temperature and humidity.
The rate of water absorbed into an unsaturated
concrete surface is measured.
Results will be used to determine the concrete’s
surface transport properties.
It will be applied on the bridge deck.
25. Test for Compressive Strength
Use core data if available
Pullout test:
Will be used to estimate the compressive strength of concrete in-situ.
Shear strength can be also be found as the test measures a combination of tensile and shear
strength.
Should be performed on a few different locations along the beam and columns to achieve a more
global estimation of compressive strength.
26. Testing for Sulphate Attack
Schmidt Rebound Hammer:
Hammer should be regularly calibrated.
Will be used predominantly along column length at regular intervals to
determine whether there is a relative loss in compressive strength at the
column base that can be possibly attributed to sulphate attack, calling for
more in-depth investigations.
27. Corrosion Repair
Members to be repaired: bridge deck and the columns
Chloride Removal:
• Electrochemical Chloride Extraction (ECE) – ONLY if justified
by chloride concentrations as it will disrupt traffic and cause
additional costs to this already expensive method.
Concrete Removal (used for concrete above the bridge deck):
• By impacting – using a pneumatic chipping hammer.
• By hydro removal – whenever the use of the pneumatic
hammer is not applicable.
Undercutting and Exposing Rebar:
• Should be done around and under all corroded rebar, so
that the rebar’s full circumference could be cleaned.
• Replace steel if 25% of cross-sectional area is lost (or 20% if
the 2 bars are in close proximity).
*NOTE: Structural review required before removal of significant
amounts of concrete to determine if support (e.g. shoring) is
required*
28. Corrosion Repair
Preventative Measure (before placing new concrete):
• Installing a discrete sacrificial anode – Zinc “puck”.
• Should be connected at joints of rebars for maximum efficiency.
• Care should be taken in placing the “pucks” to ensure that all the
steel rebar is protected.
Concrete Placement (used for concrete below the bridge deck):
• The surface should be cleaned from bond inhibiting materials by
hydroblasting.
• Form and pump placement will be implemented as it is works well
for overhead and vertical applications where congested
reinforcement is present (columns, beams, deck, and rail ends).
Consolidation and bonding is provided by the formwork pressure.
Preventative Measure (after placing new concrete):
• Applying a thin epoxy or mortar overlay all over surface to prevent
further ingress of chlorides and moisture. The epoxy would be
placed on the structural members
*NOTE: The membrane should suffice after applying ECE, but the zinc
pucks will be added for additional protection*
29. ASR Repair
Members to be repaired: bridge deck
Chemical injection with lithium salts and CO2:
• Should be done in conjunction with the
electrochemical chloride removal where the
lithium ions will replace the chlorides in the
concrete.
• Its use along with ECE may justify both their
costs
Preventative measure:
• Applying a thick overlay of ASR resistant
concrete to encapsulate the affected region and
prevent ingress of moisture.
• ASR ceases at RH < 85%
30. Crack Repair
When extensive cracking is present, it could lead
to deleterious effects and durability issues, thus
an action should be taken.
For passive cracks:
• The overlay provided for corrosion and ASR
repairs should be sufficient to provide a
moisture barrier
For active cracks:
• There were big cracks at the bottom and at the
side of the bridge deck which made us suspect
that these cracks would be active.
• Stitching of the cracks to provide a tensile force
to prevent further propagation and also acts to
close them.
• Done in conjunction with the overlays provided
before as it does not seal moisture on its own.
31. Crack Repair
The repair technique also depends on the
type of member and the location of the
crack.
For non-structural members (rail ends):
• Rout and Seal technique will be used to fill
significant cracks with flexible sealant to
minimize chemical and physical ingress.
• This method is used for its simplicity.
• It requires minimum 6mm opened space
to take sealant. In some cases, flexible
sealants and specialized coatings are used
for flexurally active cracks.
32. Crack Repair
For structural members (columns, beams and deck):
• Drilling and Plugging technique is used to core
deep and straight cracks. Then a rigid
impermeable plug of bitumen or mortar material
is inserted to replace the crack and the
deteriorated concrete around it.
• Good for walls or beams with deep vertical cracks
Preventative Measure:
• During the repairs of active cracks, NDT monitoring
such as Acoustic emission, crack width
measurement, crack inventory should be
implemented for preventative maintenance to
detect any potential crack formation. The acoustic
emission will be placed to monitor the active
cracks in the structural members, and the return
period for the crack width measurement and the
inventory will be 5 years as the bridge is in critical
condition.
33. Preventative Measures
Discrete sacrificial anode – Zinc “puck”
• Placed strategically on rebar exposed
during undercutting
• To prevent incipient anode forming
adjacent to new patch
Thin bonded overlay
• Epoxy/Mortar
• Compatibility
• Applied to columns, deck, beams and
rail ends
• Prevent further ingress of moisture and
deleterious agents
34. Preventative Measures
Thick unbonded overlay
• Concrete with its own reinforcement
• Bridge resurfacing (deck only)
• Limit permeability of underlying
concrete
• Compatibility not an issue
35. Long-term Maintenance & Monitoring
Acoustic Emission
• Set-up along deck, columns and the ends of the beams.
• Set a threshold value
• Record counts above threshold value
• Determine crack location
• Evaluate whether new crack or old one propagating
36. Long-term Maintenance & Monitoring
ILRIS-3D – Intelligent Laser Ranging and
Imaging System
o Condition status model
• Reverse engineering and load
modeling of structure
• Data is complete
• No traffic interruption
• Can be combined with monitoring
under a load test
o Micro-damage analysis
• High density scans to reveal
hairline cracks
• Apparent in both bare and coated
surfaces
37. Long-term Maintenance & Monitoring
Routine Inspection
• Should be scheduled every 2 years at the least.
• Mostly visual to determine any deterioration that is initiating
• Evaluate effectiveness of repairs done
• Crack width measurement
• Crack inventory