Department of Civil Engineering, N-W.F.P UET, Peshawar
Design of Retaining Walls
Bearing pressure of soil under various conditions of horizontal and vertical loading: It will be found that if the resultant is located within the middle third (a > l/3, where a = horizontal distance of resultant from edge of toe slab), compression will act throughout the section, and the maximum and minimum pressures can be computed from the equations shown in figure 5a. If the resultant is located just at the edge of the middle third (a = l/3), the pressure distribution is as shown in figure 5b. Rv
b
R
l/3
q1 = (4l - 6a) R2v l
a
a
q2
q1
q 2 = (6a - 2l) R2v l When a = l/2; q1 = q 2 =
l
Rv l2
(a) Rv
b
R
l/3
a
a
q2
q1
q1 =
2Rv l
q2= 0
(b) Rv
b
R
l/3
a
a 3a
q1 =
2Rv 3a
q1
(c) Figure 5: Bearing pressure for different locations of resultant.
Prof Dr. Qaisar Ali (http://www.eec.edu.pk)
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