Retaining Wall Base Width Formula

Retaining wall failures are almost always attributable to poor design or poor construction.

Retaining wall base width formula.

One key aspect of retaining wall construction is preparing a solid footing or foundation. Forces on retaining walls 6. The footing is usually made of poured concrete but in some situations homeowners may instead opt to simply use tamped earth or a gravel base. More information on retaining walls where the base trench steps up a slope.

Divide the base depth of 5 to 7 inches depending on the height of the wall by 1 944 to determine the square yardage of the depth of the gravel base beneath the wall. Insufficient footing width resulting in rotation or settlement of the wall. Thickness of the base. We recommend making the base twice as wide as the block depth to account for settling.

Insufficient stem width resulting in failure or excessive rotation of the stem. For level top surface the base width of wall is determined in the same way as the cantilever type retaining wall. Follow the block manufacturer s instructions for wall height limits. See our retaining wall cost guide to find the average price of a retaining wall.

Thoroughly planned and ably performed wall construction will help to ensure the retaining wall s stability. 600 mm wide the length of the wall the depth of the trench will be 6 in. The retaining wall should be set embedded below grade on a level base of 6 gravel or stone. Wood retaining walls 14.

150 mm plus an additional 1 in. Pier and pile foundations 11. Gabion walls 16. Width of the base.

Dig a base trench 24 in. Refer to figure a 2 below. Cantilevered tilt up walls 13. 25 mm for each 1 ft 300 mm of wall height for the amount or buried block that is needed.

Earthquake seismic design 7. Counterfort retaining walls 12. Soil bearing and stability 8. Height of the retaining wall.

Width of the toe. The interlocking retaining wall block can be used to build walls up to 24 to 36 inches high depending on the size of the block. Designing the cantilever wall stem 9. Before we proceed with the design it is important for the designer to know the geometric variable and parameters of the retaining wall.

Retaining wall base trench. Figure a 2 retaining wall geometric variables. Avoid having downspouts pointed at the retaining wall and if it s against the house keep soil and mulch well below the siding. If the wall is l feet long h feet high and t inches thick then the trench needs to be l feet long 0 12h feet deep and 2t inches wide.

Building codes and retaining walls 5. Estimate the amount of gravel needed to pack the trench at the base of the retaining wall.