Retaining walls types details with analysis and design. 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. The following worked examples have been prepared to illustrate the application of bs8002 to retaining wall design. The weight of the retaining wall including the gravity loads within it plays a vital role in performing the stability check. The following parameters influence the design of the retaining wall. A retaining wall that relies solely on its own weight to stand up is called a gravity wall.
Worked example to accompany mbie guidance on the seismic design of retaining structures for residential sites in greater christchurch version 2 november 2014. A n beal earth retaining structures worked examples 1. The report considers the role of numerical methods of analysis for the design and assessment of masonryfaced earth retaining walls. In order to evaluate the efficiency of this algorithm, an example is utilized. We believe that a twelve degree setback maximizes the leverage achieved by a battered wall, while providing a finished retaining wall that fulfills the goal of more useable flat land. Some of the many types of gravity retaining walls were described in chapter 1.
Retaining blocks are among the easiest of constructional elements used for building retaining walls. Gravity retaining walls figure a are constructed with plain concrete or stone. Design the primary force acting on a retaining wall is the pressure exerted by the retained material at the back of the wall. The wedge is defined as the soil which extends beyond the failure. 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 ab stones provide a nominal setback of twelve degrees from vertical. Design calculations alone cannot ensure that designs will yield a safe and properly functioning structure. 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. A design example which demonstrates the use of the australian. Retaining walls are structures used to retain earth or water or other materials. In this example, the structural design of the three retaining wall components is performed by hand.
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. Basics of retaining wall design page x preface to the tenth edition this tenth edition, like its predecessors, become necessary because building codes change seismic design requirements for example and as we receive suggestions for topics to be added or expanded. To change the height of a retaining wall in home designer pro open the plan in which you would like to add a retaining wall, or create a new plan. Definition and purpose retaining walls are structures that are constructed to support almost vertical steeper than 70 degrees or vertical slopes of earth masses. Definition and purpose retaining walls are structures that are constructed to support almost vertical steeper than 70 degrees or. Mar 22, 20 basics of retaining wall design 9th edition design guide for earth retaining structures. Mechanically stabilized earth mse retaining walls are growing in popularity. They depend mostly on their own weight and any soil resting on the wall for stability.
Classification of retaining walls gravity wall masonry or plain concrete. Worked example 2 design of concrete cantilever retaining. Preface standards australia has published as 46782002 for the design of earth retaining structures, which. Worked example 1 design of cantilever pol retaining walls. Lastly, to see the retaining wall, create a full camera view. Allan block combines the basic engineering principles of setback, leverage and total unit mass with simple mechanics to make highly stable gravity walls.
Where the backfill is greater than 8 ft in height, such proposed walls shall be designed. Ce 437537, spring 2011 retaining wall design example 1 8 design a reinforced concrete retaining wall for the following conditions. This example is intended to be readily calculated by hand although a lot of structural spreadsheets and software such as prokon are available. Gravity walls depend upon bulk weight for stability, as opposed to a cantilevered retaining wall fixed to a foundation. Design of retaining walls to eurocode 7 symmons madge. Analysis of the stability of masonryfaced earth retaining.
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. Basics of retaining wall design 9th edition design guide for earth retaining structures. Pdf optimum design of gravity retaining walls using charged. Flexural and shear stresses are checked in the second design example, and it is seen that they are very low in magnitude. Ce 433, fall 2006 retaining wall design example 1 8 design a reinforced concrete retaining wall for the following conditions. Precast concrete retaining wall blocks shall be vertiblock units as produced by a licensed verti. Retaining walls in theory and practice, a textbook for students. Cantilever retaining wall ouestion for the retaining wall and the profile shown below, calculate. Big block retaining wall engineering big block, inc. Gravity retaining wall cantilever retaining wall segmental retaining wall figure 1 concrete masonry retaining walls. Retaining walls in theory and practice, a textbook for.
Retaining structures i d i f it design of gravity walls eurocodes. Cantilever retaining wall reinforced concrete wall with small dimensions and it is the most economical type and the most common note. Ab engineering manual retaining walls allan block wall. Retaining wall according to method of construction can be classified as.
Course objectives they seem to crop up everywhere, like cell phone towers. The bank of supported earth is assumed to weigh 110 lbft. Types of retaining walls gravity wall depends entirely on its own weight to provide necessary stability usually constructed of plain concrete or stone masonry plain concrete gravity wall height 3 m in designing this wall, must keep the thrust line within the middle third of the base width no tensile stress to be developed. Home construction xls xls file design of retaining wall. Lateral forces on retaining wallsence 454 assakkaf design of retaining walls the design of retaining wall must account for all applied loads. Our design of retaining walls to eurocode 7 course will give delegates a basic understanding of the loads imposed by a body of soil on a wall and the ability to design simple gravity and embedded retaining walls to eurocode 7. Norfolk and tasman retaining walls au keystone retaining wall systems.
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. Design principles for gravity retaining walls soil. Some easytoadopt retaining wall design ideas have been listed below. How to choose the right retaining wall for your project. The type of retaining wall retaining walls can be broadly divided into four main categories namely, gravity walls, cantilever walls, anchored. 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. They are composed of a light form of concrete that is further blended with aggregates to make the blocks sturdier. Mcgrawhill international edition, 1997 may be referred.
Optimum design of gravity retaining walls using charged. Civil engineering excel sheets or civil engineering spreadsheets are available here for free download for members these civil engineering spreadsheets contain complete design of the structural elements. The load that presents the greatest problem and its primary concern is the lateral earth pressure induced by the retained soil. Masonry retaining wall design based on aci 53099 and aci 31802. This type of construction is not economical for walls higher than 3m. Design example number 1 25 appendix c design example number 2 34 appendix d typical specification 43. The purpose of this article is for the reader to fully understand the principle behind it. Results from pre vious large scale retaining wall tests and field studies are presented. This is not meant to be a final authority as each project has its own set of unique situations. 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. May 29, 2018 the intent of this material is to communicate the best practices for design of segmental retaining walls srw as determined by allan block corporation based on 25 plus years of research, design and field experience. In home designer pro, a retaining walls height can be specified independent of the terrain by selecting and editing the wall in 3d views. Deflection generally governs design for cantilever walls more than 18 feet high. Updated and expanded throughout, this new edition covers nearly every type of retaining strucutre. Design of semi gravity retaining walls 1 a semi gravity retaining wall consisting of plain concrete weight 145 lbft. What is the design procedure for gravity retaining wall. Flexural and shear stresses in gravity retaining walls will almost always be of minor importance. Stability limit state a limit state of loss of static equilibrium of a structure or part thereof, when considered as a rigid body. Worked example 2 design of concrete cantilever retaining walls to. Ce 537, spring 2011 retaining wall design example 1 8 design a reinforced concrete retaining wall for the following conditions.
Design principles for gravity retaining walls soil engineering. The semigravity wall is a modification of the gravity wall in which small. To further understand the designed approach, here is a worked example of the design of the retaining wall. The computation of each static and dynamic pressure acting on retaining wall need more research and site selection is becoming codified. Design of semi gravity retaining walls wec civilians. The wall environment for example whether it is adjacent to water, the soil chemistry, salinity, etc. The design principles of gravity retaining walls are discussed below. Online civil engineering courses, university courses, basics of civil engineering, lecture notes, school video training from youtube.
Pc17 retaining walls idaho transportation department. Type of retaining wall failure to design retaining walls, it is necessary to know how wall can fail. Worked example 1 design of cantilever pol retaining. Assuming that the allowable bearing pressure of the soil is 120 knm 2, the.
However, retaining wallscanalsobeconstructed for aesthetic landscaping purposes. For the earthquake load case, the foundations in loess. Reinforced soil retaining wall section pdf the information contained in the charts above were compiled by big block, inc. The safety factor against sliding minimum required f. The intent of this material is to communicate the best practices for design of segmental retaining walls srw as determined by allan block corporation based on 25 plus years of research, design and field experience. 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. 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. The objective of this research was to conduct a field performance study on a full scale cantilever retaining wall in order to verify or modifyu current design. We believe that a twelve degree setback maximizes the leverage achieved by a battered wall, while providing a finished retaining wall that fulfills the. They are not full detailed calculations such as might be prepared for a real. For details of other type the book foundation analysis and design by j. Retaining wall design example revised jim richardson. It is not advisable to include the actual strength of the retaining wall. Overturning is caused by the horizontal component of the resultant active earth pressure, p a, in the form of an overturning moment.
Degree gravel and coarse sandy backfill soil 3336 medium to fine sandy backfill soil 2932 silty sand 2730 p max k a. Design and analysis of configurations and loading conditions make it easy and increase productivity. 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. A n beal earth retaining structures worked examples. Retaining walls page 10 lateral soil pressure on retaining walls typical angle of internal friction for backfill soil soil type. D ata sheet concrete retaining walls concrete retaining walls provide a durable solution that is required of a structure in contact.
Drained strength parameters for port hills loess were assumed for the long term, gravity only load case. Basics of retaining wall design civil engineering community. If the retained earth has a surface slope that varies, then the design surface slope shall be based on an imaginary line starting from the top of the retaining wall to the highest point of the slope. 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. Retainpro is an established engineering design software specifically for retaining walls. For assistance, contact the geotechnical engineer at itd headquarters. Cantilever concrete retaining walls are commonly used for residential purposes, often as integral basement walls. Worked example 1 version 3 design of cantilever pole retaining walls to resist earthquake loading for residential sites. Retaining wall design design examples and construction. In home designer pro, a retaining wall s height can be specified independent of the terrain by selecting and editing the wall in 3d views. 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. Example 1 retaining wall designs using retaining blocks.