Design procedures are well established for overturning and sliding analyses, and. Gravity walls are built with massive blocks that use a. The following worked examples have been prepared to illustrate the application of bs8002 to retaining wall design. 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. Big block retaining wall engineering big block, inc. A n beal earth retaining structures worked examples. Definition and purpose retaining walls are structures that are constructed to support almost vertical steeper than 70 degrees or vertical slopes of earth masses. The design principles of gravity retaining walls are discussed below. V part 11 chapter 10 earth retaining strucutures vdot.
Design principles for gravity retaining walls soil. For assistance, contact the geotechnical engineer at itd headquarters. Youll see that we lead the way in retaining wall engineering. The resulting wall system is versatile, economical and relatively simple to install for even complex geometric and structural requirements. Type of retaining wall failure to design retaining walls, it is necessary to know how wall can fail. The gravity wall capability can be increased by using a precast mass.
Active earth pressure or earth pressure pa and passive earth pressure p p. Comparing the results of the retaining wall designs obtained by the other methods. 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. For example, a fill wall, such as a prefabricated modular gravity wall. The main problem geometry is available as a series of coordinates. A n beal earth retaining structures worked examples 1. For instance a retaining wall can be used to retain fill along a slope or it can be used to support a cut into a slope as illustrated in figure 1. Ce 433, fall 2006 retaining wall design example 1 8 design a reinforced concrete retaining wall for the following conditions.
Ce 537, spring 2011 retaining wall design example 1 8 design a reinforced concrete retaining wall for the following conditions. D ata sheet concrete retaining walls concrete retaining walls provide a durable solution that is required of a structure in contact. The wall and the layer of dense gravel are underlain by stiff clay. Pdf a new design method for retaining walls in clay. The load that presents the greatest problem and its primary concern is the lateral earth pressure induced by the retained soil. The design of all retaining walls needs to consider, the soil profile, soil type, clay, gravel or sand, the final height of the wall and any loadings from driveways and nearby buildings, that will increase the design forces that the wall has to withstand. Seismic displacement of gravity walls had been studied using conventional static methods for controlled displacement design. Retaining walls are usually built to hold back soil mass. Retaining walls are vertical or nearvertical structures designed to retain material on one side, preventing it from collapsing or slipping or preventing erosion. Retaining walls designing buildings wiki share your construction industry knowledge. For an additional 9 years he was a principal advisor to. The retaining wall, backfilled soils behind it and front cover soils.
Definition and purpose retaining walls are structures that are constructed to support almost vertical steeper than 70 degrees or. It also works well in situations where you need to access utilities behind the area after the wall has been built. The seismic rotating stability analysis of gravity retaining walls is always the hot research spot in geotechnical engineering. A design approach discusses the principle and concept behind and when and where to consider a retaining wall in our design. Stability limit state a limit state of loss of static equilibrium of a structure or part thereof, when considered as a rigid body. The material cost is one of the major factors in the construction of gravity retaining walls therefore, minimizing the weight or volume of these systems can reduce the cost. Course objectives they seem to crop up everywhere, like cell phone towers.
Retaining wall general notes allan block wall systems. Learn more about reinforced retaining wall construction. They are not full detailed calculations such as might be prepared for a real. Whereas, if bracing is in front of the wall and is in compression instead of tension, the wall is called buttress retaining wall. Variations on the basic design, including curves, tiers, railings, stairs, walkways and the like are making them more and more attractive to designers and architects. In this example, the structural design of the three retaining wall components is performed by hand. In order to evaluate the efficiency of this algorithm, an example is utilized.
Retaining wall construction retaining wall excel spreadsheet. Clearcalcs has calculations for a wide range of materials including wood, steel, concrete, and coldformed steel. All water collection devices such as roof downspouts, storm. Retaining wall structures can be gravity type structures, semigravity type structures, cantilever type structures, and counterfort type structures. Rubble retaining wall design pdf retaining wall design 10 edition th. 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. Mechanically stabilized earth mse retaining walls are growing in popularity. Where especially unfavorable soil conditions occur or where piling is required under a retaining wall, the assistance of an engineer is essential for design and construction. Retaining wall design engineers and geoscientists bc.
Pc17 retaining walls idaho transportation department. 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. Mr twiddle fetches polly and other stories, enid blyton, 2008, childrens stories, 192 pages. Gravity retaining wall engineering allan block wall systems. Retaining wall according to method of construction can be classified as. The problem is to be checked against eurocode 7 design approach 1 combination 1 and 2 requirements for long and short term conditions. The purpose of this technical note is to provide a guide for developing safe and economical designs for mesa retaining wall systems utilizing tensar geogrids. The bank of supported earth is assumed to weigh 110 lbft. The other two forms of construction are covered in separate guides. Unless provided within these project documents andor the project drawings. Retaining wall design design examples and construction. Analysis and design, apartment building,lift pit, shear wall, 1.
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. Worked example 2 design of concrete cantilever retaining. The grout spacing affects the wall weight, which in turn affects the seismic load. Design of semi gravity retaining walls wec civilians. Soil loadings considered in this design and calculations are based on the following parameters. 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. Retaining walls and rock walls require thought and planning just like any other building project. Some of the many types of gravity retaining walls were described in chapter 1. Results from pre vious large scale retaining wall tests and field studies are presented. Degree gravel and coarse sandy backfill soil 3336 medium to fine sandy backfill soil 2932 silty sand 2730 p max k a.
Download excel based calculation sheet for designing retaining wall perfectly. Assuming that the allowable bearing pressure of the soil is 120 knm 2, the. Below are links to the mechanical drawings for the complete line of big block retaining wall blocks. A selection of everpopular blyton short stories for the younger reader, with clear text and illustrated. Example limit states design analysis for a gravity wall. 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. Astm c172 standard practice of sampling freshly mixed concrete. Design principles for gravity retaining walls soil engineering. Calculations clearcalcs cloud structural design software.
The contract documents and contract requirements are discussed in. Worked example to accompany mbie guidance on the seismic design of retaining structures for. Site grading shall be designed to route surface water around and away from the wall. Gravity walls are built with massive blocks that use a tongueandgroove system to lock together. The safety factor against sliding minimum required f. It is not advisable to include the actual strength of the retaining wall. Retaining walls in theory and practice, a textbook for. Soil properties, wall height, wall type or function, drainage surcharge loads, adjacent grading, etc. In this study plain strain numerical analysis is performed using plaxis dynamic program where prescribed displacement is applied at the bottom boundary of the soil to simulate the applied seismic load. Seismic stability analysis of gravity retaining walls. Mcgrawhill international edition, 1997 may be referred. What is the design procedure for gravity retaining wall. Ncma design manual for segmental retaining wall, second edition.
Details, download gravity retaining wall pdf file download dwg retaining wall file. Design of semi gravity retaining walls 1 a semi gravity retaining wall consisting of plain concrete weight 145 lbft. Design the primary force acting on a retaining wall is the pressure exerted by the retained material at the back of the. Retaining walls are structure used to retain soil, rock or other materials in a vertical condition. Gravity walls depend upon bulk weight for stability, as opposed to a cantilevered retaining wall fixed to a foundation. For example, a soldier pile and lagging wall is classified as. Seismic design of retaining wall is considerably complicated problem in which assumptions have to be considered in order to make indeterminable issue solvable employing theory of statics and differential calculus. The following parameters influence the design of the retaining wall. Intro to retaining walls and excavation support systems r. Cantilever retaining wall ouestion for the retaining wall and the profile shown below, calculate. Typical construction detail drawings recon gravity. Design and detailing of counterfort retaining wall when the height of the retaining wall exceeds about 6 m, the thickness of the stem and heel slab works out to be sufficiently large and the design becomes uneconomical. This study focuses on the optimum design retaining walls, as one of the familiar types of the retaining walls which may be constructed of stone masonry, unreinforced concrete, or reinforced concrete. Design of a gravity retaining wall requires ensuring stability against sliding, and overturning.
Recon has wall charts for both gravity and geogrid reinforced walls that demonstrate. Reinforced masonry design requires that a groutreinforcement spacing be assumed. Retaining walls in theory and practice, a textbook for students. Friction angle cohesion unit weight soil type infill soil 30 0 psf 120 pcf well compacted silty, sandy clay retained soil 30 0 psf 120 pcf well compacted silty, sandy clay. The computation of each static and dynamic pressure acting on. Optimum design of gravity retaining walls using charged. Allan block combines the basic engineering principles of setback, leverage and total unit mass with simple mechanics to make highly stable gravity walls. Masonry wall design tek 145a structural 2006 keywords. Cantilever retaining wall reinforced concrete wall with small dimensions and it is the most economical type and the most common note.
Paul guyer is a registered mechanical engineer, civil engineer, fire protection engineer and architect with over 35 years experience in the design of buildings and related infrastructure. Download the excel based calculation sheets for creating the perfect design of any retaining walls as well as verifying the suitability. Retaining wall design example revised jim richardson. Exposed faces of precast concrete retaining wall blocks shall be reasonably free of large chips, cracks, or stains when viewed from a distance of 10 feet. Along with analysing and designing of this building, construction sites were also visited. A gravity wall is a retaining wall that can be built in a tight area where there isnt a lot of room to excavate.
For details of other type the book foundation analysis and design by j. Pdf optimum design of gravity retaining walls using charged. Reinforced soil retaining wall section pdf the information contained in the charts above were compiled by big block, inc. This guide covers the design of segmental concrete gravity retaining walls. A retaining wall that relies solely on its own weight to stand up is called a gravity wall. This is where geogrid comes in allan blocks reinforcement grid provides a simple solution by creating a solid structure with more resistance to soil pressure and surcharges for retaining walls under 6 ft. They provide support to terrain where the soils angle of repose is exceeded and it would otherwise collapse into a more natural form. Design of concrete cantilever retaining walls to resist earthquake loading for residential sites. Overturning is caused by the horizontal component of the resultant active earth pressure, p a, in the form of an overturning moment. Typical construction drawings for concrete retaining walls and big block retaining walls. Design of beam, column, slab, shear wall, stair case, retaining wall, water tank and an isolated footing are done.
Precast concrete retaining wall blocks shall be vertiblock units as produced by a licensed verti. Design the primary force acting on a retaining wall is the pressure exerted by the retained material at the back of the wall. Design of retaining wall with counterfort engineering. Lateral forces on retaining wallsence 454 assakkaf design of retaining walls the design of retaining wall must account for all applied loads. An introduction to retaining walls and excavation support systems j. Abarac current retaining wall design procedures are summarized with emphasis on the prediction of lateral earth pressures using the coulomb and rankine earth pressure theories, and the equivalent fluid pressure method. Retaining walls page 10 lateral soil pressure on retaining walls typical angle of internal friction for backfill soil soil type. Active earth pressure tends to deflect the wall away from the backfill. Passive resistance of the soil in front of the wall is to be included.