Department of Civil Engineering, N-W.F.P UET, Peshawar
Design of Retaining Walls
a = (96.84 – 37.10)/ 16.00 a = 3.73′ B/3 = 9.75/3 = 3.25′ < 3.73′ Therefore, resultant lies within the middle third. Hence, equations of case a of figure 5 in this document are applicable. qmax = (4l – 6a) Rv/l2 qmin = (6a – 2l) Rv/l2 l = 9.75′; a = 3.73′; and Rv = 16.00 k qmax = (4 x 9.75 – 6 x 3.73) x 16.00/9.752 = 2.79 ksf qmin = (6 x 3.73 – 2 x 9.75) x 16.00/9.752 = 0.48 ksf Allowable pressure = 8000 psf or 8 ksf > qmax, O.K. If not, increase the width (B) of the retaining wall.
8"
11'-6" 15'-0"
3.25'
3'-6"
15" 1.5' 9.75'
Figure 8: Selected dimensions of cantilever retaining wall.
Prof Dr. Qaisar Ali (http://www.eec.edu.pk)
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