Mass Concrete Retaining Wall Design

The rocla massbloc instant wall system is comprised of large permeable precast concrete blocks for various retaining applications for walls typically 2 8 metres in height.

Mass concrete retaining wall design.

Both proprietary block and crib retaining walls must be built on an in situ concrete foundation or on a compacted base course. Typical costs in 2005 is approximately 80 sf. Each course of the retaining wall should be constructed with full size concrete masonry units with an overlapping bond pattern between courses as shown in figure 3. Stone crete is used for sound barrier walls retaining walls subdivision entry walls or wherever.

A n beal earth retaining structures worked examples 2 1 0 mass concrete wall 1 1 h 4m retaining compact medium sand no water pressure. Construction is mortar less and an experienced crew can place up to 80m2 of wall per day. Another type of gravity wall is the crib retaining wall which comprises a system of interlocking header and stretcher blocks to retain the granular fill that provides the mass to the wall. Hollow or solid concrete masonry units used in gravity retaining walls should meet the requirements of astm c 90 ref.

The no fines mix aids resistance to shearing by increasing friction between units and the permeability helps to relieve hydrostatic pressure build up behind the wall. Design tanδ tan 20º or 0 75xdesign tanφ 0 364 or 0 503 design tanδ 0 364 from table design φ 33 8º design δ 20º ka 0 242 10kn m surcharge on retained soil behind wall. Table 2 table 3 soil properties table 2 compact sand. The graviti block retaining wall system comprises large precast permeable mass concrete blocks manufactured under stringent quality control.

Retaining walls designing buildings wiki share your construction industry knowledge. φ 35º 40º loose sand φ 30º 35º. Cantilever walls are economical for heights up to 10 m 32 feet. Cp2 design no surch.

The blocks are interlocked by a key joint precast into the blocks. 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. They provide support to terrain where the soil s angle of repose is exceeded and it would otherwise collapse into a more natural form. Poured concrete retaining walls can also be decorative and reproduce the look of stone or masonry.

P w due to active pressure surcharge wall self weight 1 wall self weight 2 weight of soil wall friction ia m 0 5 x 0 242 x 18 x 2. Try 1400mm thick wall. 2 and preferably have an oven dry density of 125 lb ft 2002 kg m or more. Retaining walls are vertical or near vertical structures designed to retain material on one side preventing it from collapsing or slipping or preventing erosion.

The weight of the soil mass above the heel helps keep wall stable. Based on our example in figure a 1 we have the forces due to soil pressure due to water and surcharge load to consider.