YBNY qult cN qN

where Nc*, Nq*, and NY* are (modified) bearing capacity factors, c' is the soil's effective cohesion, q the overburden pressure at the base of the embankment, Y the weight density of the foundation soil, and B the width of the embankment.

In Design Approach 1, Combination 1, partial factors on actions: Yg = 1.35 and yq = 1.5 and on material properties: y9 = Yc = 1.0 and Ycu = 1.0. For B/H = 15/2 = 7.5, Nc* = 8.1 ©, and q = 0 Rd = 16 x 8.1 = 129.6 kPa Ed = 3.5 x 18 x 1.35 + 10 x 1.5 = 100.1 kPa Rd > Ed therefore OK, degree of utilization = 77% ©

In Design Approach 1, Combination 2, partial factors on actions: yg = 1.0 and YQ = 1.3 and on material properties: y9 = Yc = 1.25 and Ycu = 1.4. For B/H = 15/2 = 7.5, Nc* = 8.1 ©, and q = 0 Rd = 16/1.4 x 8.1 = 92.6 kPa Ed = 3.5 x 18 x 1.0 + 10 x 1.3 = 76 kPa Rd > Ed therefore OK Degree of utilization = 82% ©

© For the short-term case 9 = 0 and therefore the Nq* and NY* terms do not need to be considered.

© In this example, the slope stability analysis based on DA1-2 or DA3 is critical having higher degrees of utilization than other design approaches or the bearing capacity assessment.

For a complete analysis of the problem a serviceability limit state set of calculations or assessments would need to be made to ensure that the total expected deformations were within tolerable levels.

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