Various types of retaining walls

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A retaining wall is a structure that retains (holds back) any material (usually earth) and prevents it from sliding or eroding away. It is designed so that to resist the material pressure of the material that it is holding back.


ď‚— It's possible to build Retaining Walls Services with

everyday landscaping materials such as lumber and stones, but you can also build more complicated versions that entail the use of concrete, reinforcing steel and support systems. Height is the main consideration for retaining walls; the more soil you need to hold in place, the higher the wall should be. Lumber and stone are enough for smaller retaining walls, known as gravity walls, but larger walls such as cantilever, counter fort and buttressed walls need concrete and reinforcing steel.


ď‚— These are arguably the oldest and most frequently

used Retaining Walls. They are often made from stone or other heavy materials, and rely on the weight of their own mass to resist pressures from the retained material. Gravity walls should be a minimum of 50 to 60% as thick as the height of the wall. They may have to be larger if there is a slope or surcharge on the wall. Modern gravity walls include concrete crib walls, gabions, boulders, and large, precast concrete blocks. Gabions are a type of soil strengthening, consisting of wire mesh cages into which roughly cut stone or other material is filled. Gabions work to reduce internal movement and erosive forces.



ď‚— Before the introduction of modern reinforced-soil gravity walls,

cantilevered walls were the most common type of taller retaining wall. This type of wall uses much less material than a traditional gravity wall. Cantilevered walls are made from a relatively thin stem of steelreinforced, cast-in-place concrete or mortared masonry, fixed at one end, usually by way of a simple, embedment or cantilever foundation (often in the shape of an inverted T). These rigid concrete footings must be positioned into firm suitable foundations. The wall operates like a beam — cantilevering the load to a large, fixed structural base — converting horizontal pressures from behind the wall into vertical pressures onto the ground below. Sometimes cantilevered walls are buttressed on the front, or include a counterfeit on the back, to improve their stability against heavy loads. Buttresses are short winglike walls at right angles to the main trend of the wall. Typical cantilever walls include reinforced concrete, or concrete-filled blockwork, concrete or timber sleeper walls, concrete, steel or timber sheet pile, or contiguous piling.



 These walls are pinned both top and bottom using cables,

or other stays, which are anchored in the rock or soil behind it. Anchors are driven into the material and then expanded at the end of the cable, either by mechanical means or by injecting pressurized concrete into the hole. They concrete expands to form a bulb in the soil. The wall may be embedded at the base and tied to a slab at the top or to a “deadman anchor” — a concrete structure which is driven into the ground or anchored to the earth with sufficient resistance. The horizontal cable, rod or helical anchor, and deadman structure resists forces that would otherwise cause the wall to become unstable. This method, though technically complex, is useful where high loads are expected, or where the wall itself has to be slender and would be too weak without anchoring.



ď‚— These systems do not simply consist of the wall itself, but make use of

reinforcing grids or straps to contain and stabilize the slope. The traction-resistant reinforcement elements change the nature of the soil mass and reduce the earth pressure acting on the wall. In mechanically stabilized earth (MSE) walls the soil is artificially reinforced with layered horizontal mats (geosynthetics). These mats provide additional internal shear resistance beyond that of simple gravity retaining structures. Layered steel straps may also be used. Reinforcing layers are attached to outer facing walls (typically segmental retaining walls). The wall face is usually made of precast concrete units that can tolerate some differential movement. When the reinforced soil mass is sufficiently large to retain the pressure from the soil behind it, it works with the wall to provide stability. Nailed walls make use of slender elements — normally steel reinforcing bars — which are inserted into pre-drilled hole and grouted into place. The reinforcing bars are usually installed untensioned at a slight downward angle. Isolated soil nail heads or a rigid (or flexible) facing (often of sprayed concrete) may be used on the surface of the wall.



ď‚— Piling

retaining walls in California (aka sheet pile retaining walls) consists of wood planks, steel or vinyl that has been driven into the ground and is held up by soil on either side. Piling retaining walls are used in areas with soft soil but not a lot of room to create wide barriers.  For taller piling retaining walls, a tieback anchor is used to help it stay in place. Usually, these anchors are set up behind the face of a wall and the potential failure plain of the soil. Then a cable connects the retaining wall and anchor together. It’s important to make sure that the piling retaining wall is able to endure the bending forces created by the dirt on either side of it.



ď‚— Drainage is crucial in constructing retaining walls. Drain

tiles and fabrics are used to accomplish this, along with sufficient aggregates in the base trench and backfill areas. Compacting the base trench as well as the backfill material is also important to provide a solid fill that won’t move during ground shifts and freezes. Lateral ground pressure is the No. 1 cause of failures in retaining walls; hiring a licensed engineer to study the soil and environmental status of the area is a safety measure you should keep in mind. Building codes are likely to be in play as well, so be sure to contact your local code agency before starting the project.


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consulting firm committed to providing the best highest quality engineering services in California, USA. Our professional teams always update with advances technological and engineering trends to give our client high quality services with innovative design that changing world of design and construction. To know more about the company and past project detail, please visit hcseonline.com today or you can also call us on (650) 557-4333.  HC Structure Engineer Bim Services, Home Remodeling, Retaining Walls, commercial retaining walls , Soft Story Retrofit , new construction design , home structural engineer , 3d and 4d bim modeling services etc Services Provide in USA.  Visit Our Site: http://hcseonline.com/services/retaining-walls/


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