Determine the factors of safety against sliding and overturning. Retaining walls may be defined as a wall built to resist the pressure of liquid, earth filling, sand, or other granular material filled behind it after it is built. Ce 537, spring 2011 retaining wall design example 1 8 design a reinforced concrete retaining wall for the following conditions. Seismic risk analysis of building structures in thimphu. Lateral forces on retaining wallsence 454 assakkaf design of retaining walls the design of retaining wall must account for all applied loads. The calculation checks the analysis, or analysis and design of a reinforced concrete or masonry retaining wall.
This session is not intended to teach concrete design, but more of an awareness of why things are the way they are. D ata sheet concrete retaining walls concrete retaining walls provide a durable solution that is required of a structure in contact. One is the check for an overturning moment and the other one is the check for sliding. Typical failure modes of retaining walls retaining walls normally fail due to any of the following failure modes. We have learned the different checks against the mode of failures in the retaining wall. Retaining wall analysis and design en1992en1996en1997.
Reinforced concrete cantilever retaining wall analysis and. The wall stem may be either cantilevered or propped and. A n beal earth retaining structures worked examples 1 worked examples of retaining wall design to bs8002 the following worked examples have been prepared to illustrate the application of bs8002 to retaining wall design. Type of retaining wall failure to design retaining walls, it is necessary to know how wall can fail. Calculations per aci 31811, aci 53011, ibc 2012, cbc 20, asce 7. Aashto lrfd bridge design specifications, section 11.
Gabion retaining wall design from uk supplier gabion baskets. Ers that appear as 2010 standard plans or revised standard plans are. In 1990 the concrete masonry association of australia cmaa published masonry walling guide no 4 design for earth loads retaining walls, which set out a design methodology for earth retaining structures. Cantilever concrete retaining walls are commonly used for residential purposes, often as integral basement walls. Retaining walls are structures used to provide stability for earth or other materials at their natural slopes. The passive pressure coefficients kp used in the design calculations shall be reduced as follows. To connect with me personally subscribe hinditalkwithmukesh.
They are not full detailed calculations such as might be prepared for a. Water retaining wall design calculations water retaining wall design calculations masonry retaining wall design home design ideas 663 x 1194 design of retaining wall nptel whether you making a new one for your new home or are remodeling your existing bathroom, the wall layout of the bathroom. Mcgrawhill international edition, 1997 may be referred. Various types of loads and forces acts on a retaining wall and their calculation is important for its design. Structural design of cantilever retaining wall is depend on separating each part of wall and design it as a cantilever, so its called cantilever r. The safety factor against sliding minimum required f. Engineering and design retaining and flood walls 1. The weight of the retaining wall including the gravity loads within it plays a vital role in performing the stability check. If you are not sure of your site conditions we recommend being conservative with your retaining wall heights or use geogrid in your retaining wall.
Worked example to accompany mbie guidance on the seismic design of retaining structures. General classification of walls common retaining wall types by how they resist loads retaining wall systems may be broken down into general categories based on how the structures resist load. Based upon an acceptable factor of safety against overturning, calculate the. They are not full detailed calculations such as might be prepared for a real. Mechanically stabilized earth mse retaining walls are growing in popularity. Gravity walls are the earliest known retaining structures.
Earth pressure is the pressure exerted by the retaining material on the retaining wall. Calculate lateral soil pressure and overturning moment. The lateral forces from backfill is resisted by the weight of wall itself, and due to their massive nature, they develop little or no tension. These forces on retaining wall depends on various factors which are discussed. Geotechnical design of cantilever retaining walls to. The following wall facing systems and soil reinforcement types are most commonly used and can. This appendix presents design examples of the retrofitting techniques for elevation, dry floodproofing, wet. The other two forms of construction are covered in separate guides. Cantilever retaining wall ouestion for the retaining wall and the profile shown below, calculate. Design and analysis of retaining walls 3 f crib walls or coffer dams are cells or units to be filled with soil or builtup members of pieces of precast concrete or metal and are supported by anchor pieces embedded in the soil for.
Types of retaining walls tieback wall tieback is a horizontal wire or rod, or a helical anchor use to reinforce retaining wall for stability one end of the tieback is secured to the wall, while the other end is anchored to a stable structure i. Concrete masonry reinforced cantilever retaining walls edition e3, may 20 isbn 0 909407 56 8. This design example focuses on the analysis and design of a tapered cantilever retaining wall including a comparison with model results. The mse wall design spreadsheet will be based on the following. Weber course content content section 1 retaining walls are structures that support backfill and allow for a change of grade. A n beal earth retaining structures worked examples 1. Assuming that the allowable bearing pressure of the soil is 120 knm. Design of concrete cantilever retaining walls to resist earthquake loading for. Cantilever reinforcement reinforcement counterfort 4.
Earth pressure and retaining wall basics for nongeotechnical engineers richard p. Deflection generally governs design for cantilever walls more than 18 feet high. Design and detailing of retaining walls learning outcomes. Factor of safety calculated using limiting equilibrium bishop analysis or similar. Examples c1 through c5 are a set of examples that illustrate the elevation of a singlestory home with a crawlspace. Design procedure overview page 10 vary, top to bottom. Worked example 1 design of cantilever pol retaining walls. Berrak teymur retaining walls are usually built to hold back soil mass 1. Retaining walls page 10 lateral soil pressure on retaining walls typical angle of internal friction for backfill soil soil type. Course objectives they seem to crop up everywhere, like cell phone towers. For instance a retaining wall can be used to retain fill along a slope or it can be used to. The example calculations are made here using mathcad. In general, they are used to hold back or support soil banks and water or to maintain difference in the elevation of the ground surface on each of wall sides. Surcharge large surcharge loads are induced on retaining walls in close proximity to track.
Reinforced concrete cantilever retaining wall analysis and design. Retaining walls, which set out a design methodology and safe load tables for these structures. Consider the cantilever retaining wall with the cross section shown in the above figure a. Common design issues are described in the following sections. In this example, the structural design of the three retaining wall components is performed by hand. The following worked example is for a freestanding cantilever wall that is considered sufficiently flexible for active soil pressures to be used for design. Depending upon the site conditions, type of material to be. The basic design precepts employed in cantilever walls include considerations of dead man tiebacks, taking active pressures to the bottom of the wall and considering any reductions in passive resistance for inclined slopes. Mse wall design spreadsheet summary of lrfd methodology for mse wall design design specifications the mse wall design spreadsheet will be based on the following. Jan 02, 2018 concrete volume calculation of retaining wall by learning technology official website.
Overturning when the overturning moments exceed the resisting moment offered by the components of the wall, it fails due to overturning. The cantilever retaining wall shown below is backfilled with granular material having a unit weight. Retaining walls in theory and practice, a textbook for. A design approach discusses the principle and concept behind and when and where to consider a retaining wall in our design. Degree gravel and coarse sandy backfill soil 3336 medium to fine sandy backfill soil 2932 silty sand 2730 p max k a. Final duevel arema retaining wall design for the railroad.
Lateral earth pressures and retaining walls assistant prof. Earthquake load the force exerted on the structure by earthquake action, acting on either or both the face of the retaining wall and any other structure supported by the retaining wall. Geotechnical design dublin, 14 june, 20 support to the implementation, harmonization and further development of the eurocodes eurocode 7. Spreadsheet design of mechanically stabilized earth walls. Concrete volume calculation of retaining wall by learning. Types of retaining walls gravity walls precast crib walls gabion walls reinforced concrete walls sheet pile walls ms walls mechanically stabilized slurry and secant walls soil nailing l. Unlikely to govern design unless wall is embedded into sloping ground with sloping backfill or there is a weak layer at the toe of the wall. A cantilever retaining wall must not slide horizontally. Retaining walls are structure used to retain soil, rock or other materials in a. Pdf structural calculation for reinforced concrete retaining wall. In wall stability calculations, only the embedment below this depth, known as the. Rotational forces can cause a retaining wall to overturn if the proper calculations have not been made or the wall is inadequately designed.
For retaining wall design, the applicable train liveload surcharge is the cooper e80, which can be approximated as 1,880 pounds per square foot per foot psfft of rail. Any wall that sustains significant lateral soil pressure is a retaining wall. The load that presents the greatest problem and its primary concern is the lateral earth pressure induced by the retained soil. Loads and forces acting on retaining wall and their calculations.
Lateral earth pressure calculation example the earth. The objective of this guideline is to provide information on retaining wall design in accordance with the city of nanaimo the city and the british columbia building code bcbc requirements. The details of calculations mr are tabulated below. Alternative design procedures justified in a geotechnical report may also be approved. Retaining wall can be classified according to the following. Principles of retaining wall design the constructor. Please note that the gravity wall chart provided has specific heights for specific site and soil conditions. After this present you will be able to do the completecomplete design design andand detailingdetailing ofof differentdifferent typestypes ofof. While the contents of this publication are believed to be accurate and complete, the information given is intended for general guidance and does not replace the services of professional advisers on specific projects. The focus of the guideline is the geotechnical aspects of retaining wall design. A n beal earth retaining structures worked examples.
The following worked example is for a freestanding cantilever wall that is considered. The following parameters influence the design of the retaining wall. However, retaining wallscanalsobeconstructed for aesthetic landscaping purposes. The actual load imposed on a semivertical retaining wall is dependent on eight aspects of its construction. This guide covers the design of segmental concrete gravity retaining walls. The following worked examples have been prepared to illustrate the application of bs8002 to retaining wall design. In the design of civil engineering structures, retaining walls are normally used to retain soil earth materials, and they are usually found on embankments, highways, basement of buildings, etc. They are not full detailed calculations such as might be prepared for a real wall design but are limited to the calculation of earth pressure and bearing capacity, showing how the recommendations of bs8002 are applied in practice. The minimum top thickness for reinforced concrete walls is usually 6 inches to properly place the concrete, 8inches at the bottom. There various parts of a retaining wall and design principles of these retaining wall components based on different factors and material and methods of construction are discussed. This manual provides guidance for the safe design and economical construction of retaining and flood walls. Cantilevered soldier pile retaining wall design methodology and example. Reinforced concrete wall design basics mike oshea, p. Current retaining wall design procedures are summarized with emphasis.
Gravity walls rely on their own weight and setback to hold up the soil behind them. After this present you will be able to do the completecomplete design design andand detailingdetailing ofof. Section 9 of en 19971 applies to retaining structures supporting ground i. Possible modes of failure for freestanding concrete cantilever retaining walls. Loads and forces acting on retaining wall and their. Therefore, they are usually not reinforced with steel. They are built from solid concrete or rock rubble mortared together. Worked example 2 design of concrete cantilever retaining walls to. Assuming that the allowable bearing pressure of the soil is 120 knm 2, the. This publication presents an example on the design of retaining structures. Mar 04, 2019 sketches of the retaining wall forces should be considered to properly distinguish the different forces acting on our retaining wall as tackled in the previous article, retaining wall. The retaining wall is fixed to the reinforced concrete slab foundation with a shear key for sliding resistance. Cantilever retaining walls can be precast in a factory or formed on site and considered economical up to about 25 ft in height.
Usually the cantilever wall stem is of concrete block construction rising from an insitu concrete foundation. Cantilever retaining wall reinforced concrete wall with small dimensions and it is the most economical type and the most common note. Worked examples presented at the workshop eurocode 7. We recommend that the designer refer to the best practices for srw design for design details and standards that have been proven to meld design theory with field experience. This manual is intended primarily for retaining walls which will be subjected to hydraulic loadings such as flowing water, submergence, wave action, and spray, exposure to.
Gabion retaining wall design calculations concrete. In the temporary condition no water will be taken into account. Ce 437537, spring 2011 retaining wall design example 1 8 design a reinforced concrete retaining wall for the following conditions. It is commonly required in the construction of hill roads, masonry dams, abutments and wings walls of bridges and so on. Concrete masonry association of australia cannot accept any liability whatsoever. Worked example 2 design of concrete cantilever retaining. Retaining wall design temporary condition the following calculations will consider the worst case. For details of other type the book foundation analysis and design by j. Wallpres xls calculation modules retaining walls cantilevered retainwall designing a concrete or masonry retaining wall wallpres xls static and seismic active lateral earth pressure surcharge earth pressure lateral on the retainingwallpres xlsretaining wall construction excel spreheetlateral earth pressure lateralk novo techrcc retaining wall design excel construction ofearth pressure. The design parameters for design of these ers are based on the aashto design specifications, 4 th edition, 2007, and the 2010 california amendments california amendments.