The document discusses reinforced earth walls, which combine earth and linear reinforcing strips to bear large tensile stresses. It describes how Henri Vidal came up with the concept while trying to build a reinforced sandcastle. The key components of reinforced earth walls are the soil, which is strong in compression, reinforcement like steel or concrete that is strong in tension, and a skin or facing to retain the soil. The document outlines design considerations for reinforced earth retaining walls, including checking external stability as a whole structure and internal stability of reinforcement layers.
This document provides information on reinforced earth walls, including their components and construction methodology. It discusses that reinforced earth walls combine earth and linear reinforcing strips to bear large tensile stresses. The key components are reinforcing elements, soil backfill (which can be replaced with fly ash), and a facing element. Geogrids are used as reinforcements and provide strength in tension, while fly ash or soil in the backfill provides compression strength. The document also outlines design considerations around drainage, joint materials, and stability checks for these types of walls.
This document discusses reinforced soil retaining walls. It provides an overview of the components and construction process. Reinforced soil uses soil reinforced with linear strips that can bear large tensile stresses. Retaining walls hold earth and other materials in a vertical position. Reinforced soil retaining walls were developed from the idea of reinforcing sandcastles with pine needles. They have load transfer mechanisms that use friction between the soil and reinforcement to resist shear stresses. Components include soil, facing panels, reinforcement and geosynthetics. Construction involves compacting layers of backfill soil and placing horizontal reinforcement strips. Reinforced soil retaining walls provide benefits like reduced lateral thrust, thin wall elements, simple and fast construction, and seismic resistance.
Reinforced earth is a combination of earth and linear reinforcing strips that are capable of bearing large tensile stresses.
The reinforcement provided by these strips enable the mass to resist the tension in a way which the earth alone could not. The source of this resistance to tension is the internal friction of soil, because the stresses that are created within the mass are transferred from soil to the reinforcement strips by friction.
Principles and design concepts of reinforced soil wallsPrakash Ravindran
Reinforced soil walls are cost-effective retaining structures that can tolerate large settlements. They consist of layers of soil reinforced with tensile inclusions like geogrids or geotextiles. The reinforcement improves the soil strength allowing near-vertical faces to be constructed. Key advantages include flexibility, rapid construction, and ability to absorb movements. The document discusses design principles like external stability checks against sliding and bearing capacity failure. Internal stability checks reinforcement rupture and pullout capacity. Settlements, seismic design, and typical failures are also covered.
Reinforced earth is a composite material that combines soil with tension-resistant reinforcing elements like metal sheets, strips, or nets. It was developed in 1966 by French engineer Henri Vidal and improves the engineering properties of soil. Reinforced earth is commonly used in retaining walls, embankments, and other structures due to its technical advantages and cost-effectiveness. It provides increased stability through the use of sheet, strip, or grid reinforcements made of materials like steel or synthetic polymers.
This document discusses different methods of soil stabilization, including mechanical and chemical stabilization. It provides details on two primary stabilization methods - mechanical and chemical/additive. The document also lists the advantages of soil stabilization and describes the basic ingredients and process for cement stabilization of soils for pavement construction. It gives an overview of a project rehabilitating roads in Trincomalee District, Sri Lanka after the 2004 tsunami, including photos showing the road construction and stabilization process.
This document discusses different methods for soil stabilization, including mechanical, physical, chemical, and bituminous stabilization. Mechanical stabilization involves compacting soil to increase density and strength. Physical stabilization involves blending soils or adding admixtures to improve properties. Chemical stabilization uses lime, cement, or other chemicals like calcium chloride to react with soils and modify their characteristics. Bituminous stabilization involves adding bitumen or asphalt to seal soil pores and increase cohesion between particles. The document provides details on appropriate soil types, required quantities, and construction methods for each stabilization technique.
Grouting involves injecting a slurry or liquid into soil or rock to fill voids and fractures. There are three main modes of grouting: permeation where grout flows freely into voids, compaction where grout remains intact and exerts pressure, and hydraulic fracturing where grout rapidly penetrates fractured zones. Grouting is used for applications like seepage control, soil stabilization, and vibration control. Common grout materials include suspensions of cement and water, emulsions of asphalt and water, and chemical solutions. Injection methods include permeation, compaction, jet, and soil fracture grouting. Proper planning of the grouting process including ground investigation, hole pattern, and sequencing is
This document provides information on reinforced earth walls, including their components and construction methodology. It discusses that reinforced earth walls combine earth and linear reinforcing strips to bear large tensile stresses. The key components are reinforcing elements, soil backfill (which can be replaced with fly ash), and a facing element. Geogrids are used as reinforcements and provide strength in tension, while fly ash or soil in the backfill provides compression strength. The document also outlines design considerations around drainage, joint materials, and stability checks for these types of walls.
This document discusses reinforced soil retaining walls. It provides an overview of the components and construction process. Reinforced soil uses soil reinforced with linear strips that can bear large tensile stresses. Retaining walls hold earth and other materials in a vertical position. Reinforced soil retaining walls were developed from the idea of reinforcing sandcastles with pine needles. They have load transfer mechanisms that use friction between the soil and reinforcement to resist shear stresses. Components include soil, facing panels, reinforcement and geosynthetics. Construction involves compacting layers of backfill soil and placing horizontal reinforcement strips. Reinforced soil retaining walls provide benefits like reduced lateral thrust, thin wall elements, simple and fast construction, and seismic resistance.
Reinforced earth is a combination of earth and linear reinforcing strips that are capable of bearing large tensile stresses.
The reinforcement provided by these strips enable the mass to resist the tension in a way which the earth alone could not. The source of this resistance to tension is the internal friction of soil, because the stresses that are created within the mass are transferred from soil to the reinforcement strips by friction.
Principles and design concepts of reinforced soil wallsPrakash Ravindran
Reinforced soil walls are cost-effective retaining structures that can tolerate large settlements. They consist of layers of soil reinforced with tensile inclusions like geogrids or geotextiles. The reinforcement improves the soil strength allowing near-vertical faces to be constructed. Key advantages include flexibility, rapid construction, and ability to absorb movements. The document discusses design principles like external stability checks against sliding and bearing capacity failure. Internal stability checks reinforcement rupture and pullout capacity. Settlements, seismic design, and typical failures are also covered.
Reinforced earth is a composite material that combines soil with tension-resistant reinforcing elements like metal sheets, strips, or nets. It was developed in 1966 by French engineer Henri Vidal and improves the engineering properties of soil. Reinforced earth is commonly used in retaining walls, embankments, and other structures due to its technical advantages and cost-effectiveness. It provides increased stability through the use of sheet, strip, or grid reinforcements made of materials like steel or synthetic polymers.
This document discusses different methods of soil stabilization, including mechanical and chemical stabilization. It provides details on two primary stabilization methods - mechanical and chemical/additive. The document also lists the advantages of soil stabilization and describes the basic ingredients and process for cement stabilization of soils for pavement construction. It gives an overview of a project rehabilitating roads in Trincomalee District, Sri Lanka after the 2004 tsunami, including photos showing the road construction and stabilization process.
This document discusses different methods for soil stabilization, including mechanical, physical, chemical, and bituminous stabilization. Mechanical stabilization involves compacting soil to increase density and strength. Physical stabilization involves blending soils or adding admixtures to improve properties. Chemical stabilization uses lime, cement, or other chemicals like calcium chloride to react with soils and modify their characteristics. Bituminous stabilization involves adding bitumen or asphalt to seal soil pores and increase cohesion between particles. The document provides details on appropriate soil types, required quantities, and construction methods for each stabilization technique.
Grouting involves injecting a slurry or liquid into soil or rock to fill voids and fractures. There are three main modes of grouting: permeation where grout flows freely into voids, compaction where grout remains intact and exerts pressure, and hydraulic fracturing where grout rapidly penetrates fractured zones. Grouting is used for applications like seepage control, soil stabilization, and vibration control. Common grout materials include suspensions of cement and water, emulsions of asphalt and water, and chemical solutions. Injection methods include permeation, compaction, jet, and soil fracture grouting. Proper planning of the grouting process including ground investigation, hole pattern, and sequencing is
The document discusses different types of geosynthetics including geotextiles, geogrids, geomembranes, and geocomposites. It provides details on their manufacturing processes and applications in civil engineering projects. Geotextiles include woven, nonwoven, knitted, and stitched fabrics that are used for separation, filtration, drainage, reinforcement, and erosion control. Geogrids and geomembranes are stiff polymer sheets used for reinforcement and as barriers. The document outlines common functions of geosynthetics like separation, reinforcement, filtration, drainage, and erosion control. It provides examples of their applications in walls, waste water treatment, and other civil works. Properties discussed include physical characteristics and hydraulic
Vibro replacement stone columns are a ground improvement technique to improve the load bearing capacity and reduce the settlement of the soil. On many occasions, it is noted that the local soil is, by nature, unable to bear the proposed structure, so the use of ground improvement techniques may be necessary. Use of stone columns is one such technique. The stone column consists of crushed coarse aggregates of various sizes. The ratio in which the stones of different sizes will be mixed is decided by design criteria
The document discusses various techniques for soil stabilization used in road construction. It defines soil stabilization as treating soil to maintain or improve its performance. Key techniques include mechanical stabilization by blending soils, and chemical stabilization by adding lime, cement or other chemicals. Mechanical methods improve strength through compaction and grading, while chemical additives cause reactions improving properties like strength and durability over time. The document provides details on various soil stabilization mixtures and their applications in road construction.
The presentation illustrates a technique for ground improvement, Grouting. In India, grouting is still not being used very much. In this presentation, I have demonstrated the basic types of grouting, goals of ground improvement and two case studies of grouting.
Soil nailing is a technique used to reinforce and strengthen existing ground.Soil nailing consists of installing closely spaced bars into a slope or excavation as construction proceeds from top down.It is an effective and economical method of constructing retaining wall for excavation support, support of hill cuts, bridge abutments and high ways.This process is effective in cohesive soil, broken rock, shale or fixed face conditions.
The document discusses various ground improvement techniques including removal and replacement, in-situ densification methods like dynamic compaction, preloading, use of vertical drains and stone columns. It provides details on specific in-situ densification methods like vibro-float compaction using a vibrating probe, dynamic compaction using heavy weights, and explosive compaction using detonated charges. The document also summarizes advantages and limitations of preloading using surcharge fills and uses of vertical drains and geosynthetics to accelerate consolidation.
This document discusses the construction and maintenance of bituminous roads. It describes the different types of pavements including flexible and rigid pavements. For bituminous construction, it explains the procedures for subgrade preparation, application of tack coats and prime coats, and construction of different layers using techniques like penetration macadam, bituminous macadam, and seal coating. It also discusses the use of hot mix and cold mix methods using emulsions and cutbacks for construction and maintenance of bituminous roads.
This document provides information on reinforced earth walls, including their components and construction methodology. It discusses that reinforced earth walls combine earth and linear reinforcing strips to bear large tensile stresses. The key components are reinforcing elements, soil backfill (which can be replaced with fly ash), and a facing element. Geogrids are used as reinforcements and provide strength in tension, while fly ash or soil in the backfill provides compression strength. The document also outlines design considerations for stability, drainage, and joints in reinforced earth walls.
A system of prestressing involves tensioning tendons and securing them firmly to concrete. There are two main types: pre-tensioning and post-tensioning. Pre-tensioning involves pulling tendons tight between anchored abutments before concrete is poured. The Hoyer or long-line pre-tensioning system uses bulkheads to stretch wires over which molds are placed for concrete pouring. The Freyssinet system was the first post-tensioning method, using a cable of high-strength wires grouted into a duct within the concrete beam. Wires are anchored using conical plugs pushed into holes in concrete cylinders after jacking. The Magnel Blaton system tensions wires in pairs using sandwich plates
This document summarizes the procedures for conducting a pile load test to determine the load carrying capacity of a pile. The test involves installing a test pile between two anchor piles and applying incremental loads through a hydraulic jack while monitoring settlement. Loads are applied until the pile reaches twice its safe load or a specified settlement. A load-settlement curve is plotted to determine the ultimate load and safe load based on settlement criteria. The test provides values for maximum load, permissible working load, and pile settlement under different loads.
Know the necessity of ground improvement
Understand the various ground improvement techniques available
Select design suitable ground improvement technique for existing soil conditions in the field
General presentation of under-reamed piles. Mainly for diploma engineers, it is really helpful as its objective, dimensions, usage, etc are shown with proper images. It will really helpful for the basic knowledge of under-reamed piles.
The document summarizes key aspects of prefabricated vertical drains (PVDs) used for soil improvement. It discusses how PVDs work by shortening drainage paths in clay soils to accelerate consolidation from preloading. The document covers PVD installation methods, factors affecting their performance over time, advantages over sand drains, and applications such as embankment stabilization. It also reviews several studies on PVD performance in soft soil improvement projects.
This document discusses soil mechanics concepts related to lateral earth pressure. It defines active and passive earth pressures and describes Rankine's theory and assumptions for calculating lateral pressures on retaining walls. Equations are provided for determining active and passive earth pressure coefficients and distributions for cohesionless and cohesive soils. The effects of groundwater, surcharges, and sloping backfills are also examined. Sample problems are included to calculate lateral earth pressures and forces on retaining walls for different soil and loading conditions.
The document discusses different types of pavements. It describes flexible pavements as having multiple layers that distribute loads through aggregate interlock. Rigid pavements distribute loads through the beam strength of concrete slabs. Flexible pavements are composed of surface, base, and sub-base layers over a subgrade, while rigid pavements typically only require a concrete surface layer. Both pavement types are designed to reduce loads from vehicles to prevent damage to the subgrade. The document compares advantages and disadvantages of flexible and rigid pavements.
Dewatering is the process of removing water from construction sites to allow excavation work to be done safely and efficiently below the water table. There are several reasons why dewatering is needed, including providing a dry work area, improving stability, and increasing safety. Common dewatering techniques include sump pumping, well points, deep wells, and trenches. Each method has advantages and disadvantages depending on the site conditions and depth of water lowering required. Proper planning and design of a dewatering system is important to effectively control groundwater and allow construction work to progress smoothly.
CNS layer (usefulsearch.org) (useful search) Make Mannan
A cohesive non-swelling (CNS) soil layer can be used to control swelling in expansive soils below structures. CNS soils are cohesive with low plasticity and contain non-swelling clay minerals. They exhibit little to no swelling when moisture changes and provide an environment that inhibits swelling in underlying expansive soils. Guidelines provided specify acceptable ranges for gradation, swelling pressure (≤10kN/m^2), cohesion (≥10kN/m^2), and consistency limits (LL 30-50%, PI 15-30%) for soils to qualify as CNS materials. Thickness of the CNS layer depends on the swelling pressure of the underlying soil.
This document discusses different types of soil admixtures used for ground improvement, including inert and chemical admixtures. It focuses on lime treatment of soils, describing how lime modifies soil properties through cation exchange, flocculation, and pozzolanic reactions. These reactions can increase shear strength, reduce permeability and swelling, and change plasticity. The document discusses factors in choosing lime modification or stabilization, describes lime treatment processes, and compares advantages and disadvantages of different lime application methods.
Reinforced earth is a building technique that combines soil and flexible reinforcing strips to create structures capable of bearing large tensile stresses. The reinforcement strips enable the soil mass to resist tension through friction between the soil and strips. Reinforced earth structures offer advantages like light construction materials, rapid construction, elimination of differential settlement, and land savings. They consist of soil, a facing element, and internal reinforcing materials like steel or geotextiles. Reinforced earth can be used to construct retaining walls, bridge abutments, culverts, and other structures. Design considers external stability against sliding, overturning, and internal stability of reinforcement layers. Reinforced earth walls performed well during seismic events.
The document discusses reinforced earth, which combines earth and reinforcing strips capable of bearing large tensile stresses. The reinforcement enables the mass to resist tension that earth alone could not. The idea originated from Henri Vidal trying to build a reinforced sandcastle. Reinforced soil structures use light, easy to construct materials and require only basic machinery. They eliminate differential settlement, increase bearing capacity, and can save land area. Components include soil, skin, and reinforcement arranged in layers. The document discusses design considerations for reinforced earth retaining walls and their seismic stability.
The document discusses different types of geosynthetics including geotextiles, geogrids, geomembranes, and geocomposites. It provides details on their manufacturing processes and applications in civil engineering projects. Geotextiles include woven, nonwoven, knitted, and stitched fabrics that are used for separation, filtration, drainage, reinforcement, and erosion control. Geogrids and geomembranes are stiff polymer sheets used for reinforcement and as barriers. The document outlines common functions of geosynthetics like separation, reinforcement, filtration, drainage, and erosion control. It provides examples of their applications in walls, waste water treatment, and other civil works. Properties discussed include physical characteristics and hydraulic
Vibro replacement stone columns are a ground improvement technique to improve the load bearing capacity and reduce the settlement of the soil. On many occasions, it is noted that the local soil is, by nature, unable to bear the proposed structure, so the use of ground improvement techniques may be necessary. Use of stone columns is one such technique. The stone column consists of crushed coarse aggregates of various sizes. The ratio in which the stones of different sizes will be mixed is decided by design criteria
The document discusses various techniques for soil stabilization used in road construction. It defines soil stabilization as treating soil to maintain or improve its performance. Key techniques include mechanical stabilization by blending soils, and chemical stabilization by adding lime, cement or other chemicals. Mechanical methods improve strength through compaction and grading, while chemical additives cause reactions improving properties like strength and durability over time. The document provides details on various soil stabilization mixtures and their applications in road construction.
The presentation illustrates a technique for ground improvement, Grouting. In India, grouting is still not being used very much. In this presentation, I have demonstrated the basic types of grouting, goals of ground improvement and two case studies of grouting.
Soil nailing is a technique used to reinforce and strengthen existing ground.Soil nailing consists of installing closely spaced bars into a slope or excavation as construction proceeds from top down.It is an effective and economical method of constructing retaining wall for excavation support, support of hill cuts, bridge abutments and high ways.This process is effective in cohesive soil, broken rock, shale or fixed face conditions.
The document discusses various ground improvement techniques including removal and replacement, in-situ densification methods like dynamic compaction, preloading, use of vertical drains and stone columns. It provides details on specific in-situ densification methods like vibro-float compaction using a vibrating probe, dynamic compaction using heavy weights, and explosive compaction using detonated charges. The document also summarizes advantages and limitations of preloading using surcharge fills and uses of vertical drains and geosynthetics to accelerate consolidation.
This document discusses the construction and maintenance of bituminous roads. It describes the different types of pavements including flexible and rigid pavements. For bituminous construction, it explains the procedures for subgrade preparation, application of tack coats and prime coats, and construction of different layers using techniques like penetration macadam, bituminous macadam, and seal coating. It also discusses the use of hot mix and cold mix methods using emulsions and cutbacks for construction and maintenance of bituminous roads.
This document provides information on reinforced earth walls, including their components and construction methodology. It discusses that reinforced earth walls combine earth and linear reinforcing strips to bear large tensile stresses. The key components are reinforcing elements, soil backfill (which can be replaced with fly ash), and a facing element. Geogrids are used as reinforcements and provide strength in tension, while fly ash or soil in the backfill provides compression strength. The document also outlines design considerations for stability, drainage, and joints in reinforced earth walls.
A system of prestressing involves tensioning tendons and securing them firmly to concrete. There are two main types: pre-tensioning and post-tensioning. Pre-tensioning involves pulling tendons tight between anchored abutments before concrete is poured. The Hoyer or long-line pre-tensioning system uses bulkheads to stretch wires over which molds are placed for concrete pouring. The Freyssinet system was the first post-tensioning method, using a cable of high-strength wires grouted into a duct within the concrete beam. Wires are anchored using conical plugs pushed into holes in concrete cylinders after jacking. The Magnel Blaton system tensions wires in pairs using sandwich plates
This document summarizes the procedures for conducting a pile load test to determine the load carrying capacity of a pile. The test involves installing a test pile between two anchor piles and applying incremental loads through a hydraulic jack while monitoring settlement. Loads are applied until the pile reaches twice its safe load or a specified settlement. A load-settlement curve is plotted to determine the ultimate load and safe load based on settlement criteria. The test provides values for maximum load, permissible working load, and pile settlement under different loads.
Know the necessity of ground improvement
Understand the various ground improvement techniques available
Select design suitable ground improvement technique for existing soil conditions in the field
General presentation of under-reamed piles. Mainly for diploma engineers, it is really helpful as its objective, dimensions, usage, etc are shown with proper images. It will really helpful for the basic knowledge of under-reamed piles.
The document summarizes key aspects of prefabricated vertical drains (PVDs) used for soil improvement. It discusses how PVDs work by shortening drainage paths in clay soils to accelerate consolidation from preloading. The document covers PVD installation methods, factors affecting their performance over time, advantages over sand drains, and applications such as embankment stabilization. It also reviews several studies on PVD performance in soft soil improvement projects.
This document discusses soil mechanics concepts related to lateral earth pressure. It defines active and passive earth pressures and describes Rankine's theory and assumptions for calculating lateral pressures on retaining walls. Equations are provided for determining active and passive earth pressure coefficients and distributions for cohesionless and cohesive soils. The effects of groundwater, surcharges, and sloping backfills are also examined. Sample problems are included to calculate lateral earth pressures and forces on retaining walls for different soil and loading conditions.
The document discusses different types of pavements. It describes flexible pavements as having multiple layers that distribute loads through aggregate interlock. Rigid pavements distribute loads through the beam strength of concrete slabs. Flexible pavements are composed of surface, base, and sub-base layers over a subgrade, while rigid pavements typically only require a concrete surface layer. Both pavement types are designed to reduce loads from vehicles to prevent damage to the subgrade. The document compares advantages and disadvantages of flexible and rigid pavements.
Dewatering is the process of removing water from construction sites to allow excavation work to be done safely and efficiently below the water table. There are several reasons why dewatering is needed, including providing a dry work area, improving stability, and increasing safety. Common dewatering techniques include sump pumping, well points, deep wells, and trenches. Each method has advantages and disadvantages depending on the site conditions and depth of water lowering required. Proper planning and design of a dewatering system is important to effectively control groundwater and allow construction work to progress smoothly.
CNS layer (usefulsearch.org) (useful search) Make Mannan
A cohesive non-swelling (CNS) soil layer can be used to control swelling in expansive soils below structures. CNS soils are cohesive with low plasticity and contain non-swelling clay minerals. They exhibit little to no swelling when moisture changes and provide an environment that inhibits swelling in underlying expansive soils. Guidelines provided specify acceptable ranges for gradation, swelling pressure (≤10kN/m^2), cohesion (≥10kN/m^2), and consistency limits (LL 30-50%, PI 15-30%) for soils to qualify as CNS materials. Thickness of the CNS layer depends on the swelling pressure of the underlying soil.
This document discusses different types of soil admixtures used for ground improvement, including inert and chemical admixtures. It focuses on lime treatment of soils, describing how lime modifies soil properties through cation exchange, flocculation, and pozzolanic reactions. These reactions can increase shear strength, reduce permeability and swelling, and change plasticity. The document discusses factors in choosing lime modification or stabilization, describes lime treatment processes, and compares advantages and disadvantages of different lime application methods.
Reinforced earth is a building technique that combines soil and flexible reinforcing strips to create structures capable of bearing large tensile stresses. The reinforcement strips enable the soil mass to resist tension through friction between the soil and strips. Reinforced earth structures offer advantages like light construction materials, rapid construction, elimination of differential settlement, and land savings. They consist of soil, a facing element, and internal reinforcing materials like steel or geotextiles. Reinforced earth can be used to construct retaining walls, bridge abutments, culverts, and other structures. Design considers external stability against sliding, overturning, and internal stability of reinforcement layers. Reinforced earth walls performed well during seismic events.
The document discusses reinforced earth, which combines earth and reinforcing strips capable of bearing large tensile stresses. The reinforcement enables the mass to resist tension that earth alone could not. The idea originated from Henri Vidal trying to build a reinforced sandcastle. Reinforced soil structures use light, easy to construct materials and require only basic machinery. They eliminate differential settlement, increase bearing capacity, and can save land area. Components include soil, skin, and reinforcement arranged in layers. The document discusses design considerations for reinforced earth retaining walls and their seismic stability.
This document provides information on various retaining wall technologies. It discusses gravity walls, crib walls, gabion walls, cantilever walls, sheet pile walls, and types of materials that can be used for retaining walls like wood, steel, concrete. It also summarizes different retaining wall systems like MSE walls, precast panel walls, counterfort walls, modular block walls, and vegetated soil bioengineering systems. The document highlights the advantages of each technology which include fast construction, flexibility, durability, and cost-effectiveness.
here we know about Types , uses and selection of a retaining wall and their stability
overturning
sliding
Bearing capacity failure
comparison
soil nailing
This document discusses different types of retaining walls and their construction methods. It describes gravity walls, sheet pile walls, cantilever walls, and anchored walls. It also discusses soil nailing, diaphragm walls, and bracing used for deep excavations. Key details include the steps for constructing retaining walls, advantages of concrete walls, advantages and disadvantages of CFA piles, applications and materials used for soil nailing, and the sequence of work for installing diaphragm walls. A case study describes an L-shaped cantilever retaining wall project in New Cairo City.
Research study on Soil Structure Interaction of Integrated Earth Retaining Wa...IRJET Journal
This document summarizes research on soil-structure interaction of integrated earth retaining walls. It discusses how precast concrete retaining walls can be constructed more quickly and cost effectively using interlocking blocks with mortar-less joints. The research aims to analyze such integrated retaining walls and evaluate their strength and deformation under lateral soil pressures through modeling in ANSYS software. Prior studies on precast retaining walls, soil-structure interaction, and use of relief shelves to increase wall stability are also reviewed.
Independant study on Reinforced soil retaining wallparas6904
1. Reinforced soil retaining walls combine earth and linear reinforcement strips to resist tensile stresses that earth alone cannot. Henri Vidal first developed the concept by reinforcing a sandcastle with pine needles.
2. The document discusses the components, construction procedure, cost comparison, applications and benefits of reinforced soil retaining walls. It includes load transfer mechanisms, modes of failure, and principles of reinforced soil walls.
3. A literature review covers experimental and analytical studies on reinforced soil walls from 1992 to 2013 related to earth pressures, seismic performance, backfill properties, and geosynthetic reinforcements. Gaps in existing research are identified for further study.
Reinforced earth is a construction material made of soil reinforced with horizontal layers of flexible inclusions like metal strips, grids, or fabric. It was invented in 1963 and is used widely in retaining walls, dams, bridge abutments, and other structures. The key components are soil, reinforcement, and a facing. The soil is confined by the reinforcement which resists the soil's lateral deformation under load. When loaded vertically, the soil wants to spread but is restrained by the reinforcement, which develops tensile forces that contribute to the structure's stability. Reinforced earth structures offer advantages like requiring less fill material and allowing steeper slopes, saving space. They can also be constructed directly on soft ground.
This document discusses different types of retaining walls, including:
- Gravity walls, pre-cast crib walls, gabion walls, reinforced concrete walls, sheet pile walls, mechanically stabilized earth (MSE) walls, slurry walls, secant pile walls, soldier piles and lagging walls, cofferdam walls, and hybrid systems.
It provides details on the materials, designs, and uses of various retaining wall types. Common materials include wood, steel, concrete, and soil reinforcements. Walls are chosen based on factors like height, site conditions, costs, and whether they are temporary or permanent.
MECHANICALLY STABILIZED EARTH WALLS AND REINFORCED SOIL SLOPES (1).pptxShahidAmeen10
The document provides an introduction to mechanically stabilized earth walls and reinforced soil slopes, including:
- A historical overview of soil reinforcement techniques dating back centuries and the modern development of MSE walls and RSS in the 1960s.
- Definitions of key terminology used in design and construction of MSE walls and RSS.
- Details on the objectives, scope, and source documents for the guidelines on MSEW and RSS design and construction.
- A list of major manufacturers and suppliers of materials used in MSE walls and RSS.
1. Concrete beams, columns, slabs, walls and staircases were constructed on site using formwork and reinforcement bars.
2. For beams and columns, formwork was erected, reinforcement bars were installed, and then concrete was poured and allowed to cure.
3. Concrete slabs were either precast off site or cast in place using formwork, reinforcement, and concrete pouring and curing.
4. Walls were constructed using concrete bricks laid with mortar.
This document discusses wall materials and construction techniques for disaster resistant buildings. It covers different types of masonry bonds used in walls like rat trap bond and English bond. It discusses wall geometry and how factors like height, length, and reinforcement placement affect wall strength. It also addresses openings, wall and beam reinforcements, and field testing of construction materials like bricks and cement to ensure quality. The goal is to understand wall design and construction methods that improve a building's ability to withstand disasters.
1. Structures in Kobe built since 1981 that were designed to strict seismic codes mostly withstood the 1995 Kobe earthquake, while newly built ductile-frame high-rise buildings were generally undamaged.
2. Modern earthquake engineering aims to create earthquake-resistant designs and construction techniques to build all types of structures, using state-of-the-art technology, materials science, and testing.
3. Key strategies for earthquake-resistant design include base isolation, increasing damping, and using devices like viscous and friction dampers to absorb seismic energy.
This document discusses different types of retaining walls and their uses. It provides details on:
- What retaining walls are and common construction materials like concrete, wood, and interlocking blocks.
- Applications such as supporting road embankments, separating roads from highways, and preventing erosion.
- Specific types like gravity walls, pre-cast crib walls, gabion walls, reinforced concrete, and mechanically stabilized earth walls.
- Design considerations for different wall types and factors of safety in designs.
Masonry refers to construction materials formed by combining masonry units like stone and brick with mortar. Masonry walls can be load-bearing exterior walls or non-load bearing interior partition walls. Masonry walls are categorized based on their structure, location, and construction method. Common masonry units include clay bricks, structural clay tiles, and concrete masonry units which vary in properties based on their composition, manufacturing process, and intended use.
The document discusses categories of buildings for seismic resistance. It identifies three key parameters for categorizing buildings: 1) the seismic intensity zone where it is located, 2) the building's importance, and 3) the stiffness of the foundation soil. Based on these parameters, buildings are graded to determine the appropriate level of seismic strengthening. Important buildings like hospitals and schools require more strengthening, while ordinary buildings like houses and offices require less. The document provides guidelines on site selection, building plan, shape, mass, and following standard design codes to achieve seismic safety.
Retaining walls are used to retain earth (or other material) in a vertical position at locations where an abrupt change in ground level occurs.
The walls therefore prevents the retained earth from assuming its natural angle of repose.
This document discusses various building materials used in construction. It describes stones, bricks, lime, cement and concrete. Stones are classified based on their geological, physical and chemical properties. Different types of stones are used in building foundations, walls and other structures. Bricks are manufactured by molding and firing clay and are classified based on their quality. Concrete is produced by mixing cement, aggregates like sand and gravel, and water. Reinforced cement concrete combines concrete with steel reinforcement to provide strength. Cement acts as the binding agent in concrete and is made from limestone. Limestone has various uses in construction as well as other industries. The document outlines the composition and uses of key construction materials.
Comparative Review on Reinforced Soil and Reinforced Soil StructuresIRJET Journal
This document provides a review of reinforced soil and reinforced soil structures. It begins with an abstract that discusses the history of reinforced earth construction and modern reinforcing materials like geosynthetics. The document then reviews the literature on reinforced soil techniques. It describes different types of reinforcing materials that have been used, including natural materials like jute, bamboo and coir as well as modern geosynthetics. It provides details on the components of reinforced soil structures, including reinforcing elements, backfill soil, and facing elements. It discusses various types of reinforcing elements such as strips, grids, anchors and composites. It also describes considerations for backfill soil and different types of facing elements. Overall, the document presents information on
The Science of Learning: implications for modern teachingDerek Wenmoth
Keynote presentation to the Educational Leaders hui Kōkiritia Marautanga held in Auckland on 26 June 2024. Provides a high level overview of the history and development of the science of learning, and implications for the design of learning in our modern schools and classrooms.
How to Create User Notification in Odoo 17Celine George
This slide will represent how to create user notification in Odoo 17. Odoo allows us to create and send custom notifications on some events or actions. We have different types of notification such as sticky notification, rainbow man effect, alert and raise exception warning or validation.
CapTechTalks Webinar Slides June 2024 Donovan Wright.pptxCapitolTechU
Slides from a Capitol Technology University webinar held June 20, 2024. The webinar featured Dr. Donovan Wright, presenting on the Department of Defense Digital Transformation.
How to Create a Stage or a Pipeline in Odoo 17 CRMCeline George
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2. Objective:
Our objective is to do a brief study on various reinforced earth
walls and to identify the various defects and improvement
techniques.
To explain in detail about the construction methodology of
Reinforced Earth Wall.
3. What is a reinforced earth wall?
Reinforced earth wall is a combination of earth and linear
reinforcing strips that are capable of bearing large tensile stresses.
Soil :- strong in compression.
Reinforcement:-strong in tension.
Ancient reinforcement:-tree branches , roots of vegetation , tree
trunks , straw , bamboo etc.,
Modern reinforcement:-Steel , Concrete , Glass fibre , Wood ,
Rubber , Aluminium.
4. History
Henri Vidal, a highway engineer and architect, was trying to built a
sandcastle on the beach. But the sand kept on falling off and this led to
the idea of reinforcing the construction with pine needles. That is how
the general principle of Reinforced Earth came about.
6. Selection of soil for the Reinforced Zone
It should be granular, cohesion less material, not too much silt or clay having
particle size not more than 125 mm.
Plasticity Index (PI) shall not exceed 6.
The materials shall be substantially free of shale or other soft, poor durability
particles.
The material shall have a magnesium sulfate soundness loss (or an equivalent
sodium sulfate value) of less than 30 percent after four cycle.
The fill material must be free of organic matter and other deleterious substances, as
these materials not only enhance corrosion but also result in excessive settlements.
Pea gravel ( a backfill material of good quality in terms of both friction and
drainage )is recommended to prevent buildup of high lateral pressures from the
compaction and to prevent facing panel movement.
7. Back Fill requirements for the Reinforced Zone
Recommended limits of electrochemical
properties for backfills when using steel
reinforcement
Recommended backfill requirements for
MSE & RSS construction
8. Skin or Facing
Skin is the facing element of the reinforced soil wall.
These elements keeps the reinforcement at a desired elevation in the reinforced soil wall
and also protect the granular at the edge falling off.
Made of either metal units or precast concrete panels.
9. Reinforcing Material
A variety of materials can be used as reinforcing materials e.g,
Steel
Concrete
Glass fibre
Wood
Rubber
Aluminium
Reinforcement may take the form of strips, grids, anchors & sheet material, chains,
planks, rope, vegetation and combinations of these or other material forms.
Image of some geogrids
10.
11. Design of Reinforced Earth Retaining Wall
In the reinforced earth wall two type of stability checked:
External stability : It consider the reinforced structure as whole and check the stability for
sliding, overturning, bearing/tilt and slip by considering the effects of dead loads, other loads
(live load, dynamic load etc.) and forces acting on the structure.
Internal stability:
It cover internal mechanism ( tension and pull out failure) such as shear within the structure ,
arrangement and behavior of the reinforcement and backfill. It checks the stability for each
reinforcement layers and stability of wedges within the reinforced fill
Seismic Stability:
High performance during the 1995 Kobe Earthquake of a GRS RW of this type that
had been constructed at Tanata validated its high seismic stability
12. WORK CARRIED OUT SO FAR:
Visited the flyover near green circle-New Bus Stand –Vellore.
Gathered information about reinforced earth walls on web.
We have concentrated only on the basic concepts.
13. RESULTS:-
Reinforced earth walls have evolved as viable technique and contributed to
infrastructure in
Terms of speed , ease of construction , economy , aesthetics etc.
It is a technology that needs to be understood well in terms of its response,
construction features etc.
Do not require experienced craftsmen with special skills for construction.
Require little site preparation.
Need little space in front of the structure for construction operations.
Do not need rigid, unyielding foundation support, because reinforced or
mu1tianchored structures are tolerant to deformations.
14. Discussions:-
Require a relatively large space behind the wall face to obtain enough wall
width for internal and external stability.
Require granular fill (At sites where there is a lack of granular soils, the cost
of importing suitable fill material may render the system uneconomical).
Usually require a drainage system for ground nailing which may be difficult
to construct and maintain.
Corrosion of steel reinforcing elements, deterioration of certain types of
exposed facing elements such as fabrics or plastics by ultra violet rays, and
degradation of plastic reinforcement in the ground may occur so it must be
addressed in each project by means of suitable design criteria.
Soil nailings a method of reinforcing in-situ soil by the
insertion long metal rods (nails) into an otherwise undisturbed
natural soil mass. The technique is used to stabilize existing
potentially unstable slopes and to support the side walls of
excavations.
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