Active earth pressure tends to variation of earth pressure deflect the wall away from the 5. Cantilevered soldier pile retaining wall design methodology and example. Cantilever retaining wall ouestion for the retaining wall and the profile shown below, calculate. Cantilever retaining wall sheet excel web share 20161018t23. It is so named because its individual parts toe, heel, and stem. Usually the cantilever wall stem is of concrete block.
It has much thinner stem and utilize the weight of the backfill soil to provide most of the resistance to sliding and overturning. Design and detailing of retaining walls learning outcomes. Cantilever retaining wall reinforced concrete wall with small dimensions and it is the most economical type and the most common note. It is considered suitable for common residential situations with competent soils. Full details of masonry wall construction are provided in reinforced concrete masonry cantilever retaining walls design and. Norfolk and tasman retaining walls au keystone retaining wall systems. This objective has been accomplished and the proposed. The safety factor against sliding minimum required f.
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. Example 11 castinplace concrete cantilever retaining wall 4 2020 summary of unfactored loads and moments resolve moments about point a see figure 1 typical section load combinations ev 1 ev 2 dc 2 dc 3 vehicular collision load 18. Strength limit state a limit state of collapse or loss of structural integrity of the components of the. 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. Calculate the factors of sa fety with respect to overturning, sliding, and bearing capacity. Active earth pressure tends to deflect the wall away from the backfill. This gl pressure tends to deflect the wall outward. Design and detailing of retaining walls engineering books. Worked example to accompany mbie guidance on the seismic design of retaining structures for residential sites in greater christchurch version 2 november 2014. Cantilever retaining wall sheet excel civil engineering program. Cantilever retaining wall is the most common type of earthretaining structure. Cantilever rc retaining wall 10 knm2 m 500 mm h 400 0. Retaining wall development is described in section 11555 of the.
Stability limit state a limit state of loss of static equilibrium of a structure or part thereof, when considered as a rigid body. This publication presents an example on the design of retaining structures. This costeffective solution completely eliminates the need for the construction of a mechanically stabilized earth zone behind the wall and requires substantially less excavation than is usually necessary in a gridreinforced wall. 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. Cantilever walls are walls that do not have any supports and thus have a free unsupported excavation. The focus of the guideline is the geotechnical aspects of retaining wall design. Check against a worked example in the reference above. Cantilever retaining wall functions and design considerations. Earth pressure p 8 earth pressure is the pressure exerted by the retaining material on the retaining wall. Cantilever concrete retaining walls are commonly used for residential purposes, often as integral basement walls.
Section 9 of en 19971 applies to retaining structures supporting ground i. Geotechnical design of cantilever retaining walls to. Reinforced concrete cantilever retaining wall analysis and design aci 318m14 reinforced concrete cantilever retaining walls consist of a relatively thin stem and a base slab. Cantilever walls restrain retained earth by the passive resistance provided by the soil below the excavation. When retaining wall is designed for impact loads, the stem should be checked at equally spaced points along stem length from top to the bottom as impact load spread at the greater length of the stem. The stem may have constant thickness along the length or may be tapered based on economic and construction criteria. Reinforced concrete cantilever retaining wall analysis and design. Stepbystep design of a cantilevered retaining wall. Reinforced concrete cantilever retaining wall analysis and. The following text provides a general discussion and design guidelines for these flexible wall. Assuming that the allowable bearing pressure of the soil is 120 knm. Design example the following design example briefly illustrates some of the basic steps used in the allowable stress design of a reinforced concrete masonry cantilever retaining wall. P a active earth pressure or earth pressure pa and passive earth pressure pp.
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. A wall number is assigned as per criteria discussed in. Jun 10, 2018 numerical of cantilever retainig wall is discussed in this video in a simple manner. Cantilever walls the cantilever wall figure 1b and figure 2 is the most common type of retaining structure and generally is used for walls in the range from 10 to 25 ft in height. Concrete masonry reinforced cantilever retaining walls edition e3, may 20 isbn. Consider the cantilever retaining wall with the cross section shown in the above figure a.
Conventional retaining walls gravity retaining structures stability depends on the self weight of the wall not economical for design semigravity retaining structures minimum amount of reinforcement may be used in the wall to reduce the size of wall cantilever retaining walls reinforced concrete is used in wall design with thin stem and slab base. Examples of this include cip cantilever, mse and modular block walls. Assume level backfill, no surcharge or seismic loading, active earth. This design example focuses on the analysis and design of a tapered cantilever retaining wall including a comparison with model results. This procedure is intended to be readily calculated by hand, although use of. Gravity wallmasonry or plain concrete cantilever retaining wallrcc inverted t and l.
Retaining walls 101 an introduction to choosing the. Basics of retaining wall design 10 editionth a design guide for earth retaining structures contents at a glance. Worked example 2 design of concrete cantilever retaining. Design retaining wall for car bumper might be necessary when the wall extends above grade, and the parking area is close to it. An example of this is the anchorplex retaining wall system developed by anchor wall systems of oldcastle apg. For many years reinforced masonry cantilever retaining walls, relying on gravity loads to resist the overturning forces due to soil pressure, have been constructed. Cantilever retaining wall is the most common type of earth retaining structure. Cantilever retaining walls are the most common type of retaining walls and are generally used for wall high up to 8m. In such a case counterforts having trapezoidal section fixed at the base slab are provided at intervals of 1. The following design example briefly illustrates some of the basic steps used in the allowable stress design of a reinforced concrete masonry cantilever retaining wall. It derives its name from the fact that its individual parts behave. Rccii design steps for cantilever retaining wall youtube. Some other basic concepts are also explained like, curtailment of bars development length.
Ce 537, spring 2011 retaining wall design example 3 8 3. Design the reinforced concrete masonry cantilever retaining wall shown in. Numerical of cantilever retainig wall is discussed in this video in a simple manner. 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 procedures.
Active earth pressure or earth pressure pa and passive earth pressure p p. The base is divided into two parts, the heel and toe. Design the reinforced concrete masonry cantilever retaining wall shown in figure 2. Cantilever retaining wall with shear keywith shear key batter drainage hole toe 2.
Assuming that the allowable bearing pressure of the soil is 120 knm 2, the. Cantilever retaining walls figure b are made of reinforced concrete that. Design of cantilever sheet pile walls january 2015. Possible modes of failure for freestanding concrete cantilever retaining walls. The following worked example uses a simplified lrfd design procedure with load and resistance factors taken from b1vm4.
Ce 437537, spring 2011 retaining wall design example 3 8 3. Retaining walls 101 an introduction to choosing the right wall. Gabion retaining wall design from uk supplier gabion baskets. Retaining walls types details with analysis and design. Cantilever retaining wall are usually of reinforced concrete and work on the principles of leverage.
The stem is a vertical cantilever beam, acted on by the horizontal earth pressure. The cantilever retaining wall shown below is backfilled with granular material having a unit weight. This is an extremely popular system offering benefits that include zero lot lines, a vertical wall face and a range of possible finishes. Consider the cantilever retaining wall with the crosssection shown in the above figure a. Cantilever retaining wall sheet excel civil engineering. The details of a cantilever retaining wall are shown below, is the design of the wall satisfactory. Preface standards australia has published as 46782002 for the design of earth retaining structures, which.
Classification of retaining walls cantilever retaining wallrcc inverted t and l. Worked example 2 design of concrete cantilever retaining walls to. Loads and forces acting on retaining wall and their calculations the next step is to enter the loads on the wall as defined above. Determine the factors of safety against sliding and overturning. Reinforced concrete cantilever retaining wall analysis and design aci 31814 reinforced concrete cantilever retaining walls consist of a relatively thin stem and a base slab. Ahmadi and varaee, 5 used particle swarm algorithm to optimize the cantilever reinforced retaining wall and it is indicted that there is.
Design concrete shear stress in wall section for inplane bending. However, retaining walls can also be constructed for aesthetic landscaping purposes. It is so named because its individual parts toe, heel, and stem behave as, and design as, cantilever beams. 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.
The following worked example is for a freestanding cantilever wall that is considered sufficiently flexible for active. Mar 07, 2017 here i had explained about the design steps for a cantilever retaining wall as per my knowledge. Deflection generally governs design for cantilever walls more than 18 feet high. Some other basic concepts are also explained like, curtailment of bars development length distribution. Wisdot regional staff determines the need for permanent retaining walls on highway projects. The design of a retaining wall must account for all applied loads. Suggest suitable dimensions for the rc retaining wall example 1. Loads and forces acting on retaining wall and their.558 1136 793 960 633 920 673 527 455 243 206 313 128 1319 1268 122 1448 1502 99 1277 1055 705 476 343 1058 893 602 938 143 537 1311 1046 948 1305 823 1163 1391 1019 1067 555