Overview

Test Case

The Mohr-Coulomb material model is used to model sand. The UY DOF are constrained at Y = 0 meters, and the UX DOF are constrained at location X = 0 meters and at X = 10 meters. The model is subjected to a gravity load along the global Y-direction and a tapered UX displacement at location X = 0 meters, as shown in Figure 322: Earth Pressure Problem Sketch. The lateral earth pressure coefficient at the left edge of OA is calculated and compared with the reference solution.

Figure 322: Earth Pressure Problem Sketch

Material Properties	Geometric Properties	Loading
E = 26.67 x 106 MPa = 0.333 = 1800 kg/m3 Mohr-Coloumb model Friction angle, = 30 ° Residual friction angle, = 30 ° Cohesion, c = 0 Residual cohesion, cr = 0 Dilatancy angle, = 30 °	B = H = 10 m	Acceleration due to gravity (Y-direction) = 9.81 m/sec2 Displacement in X direction with gradient -0.003 x (Y-coordinate of selected node) applied on nodes at location X = 0 m

Analysis Assumptions and Modeling Notes

The problem is modeled using 2D PLANE182 elements with plane strain element behavior and with simplified enhanced strain formulation. The Mohr-Coloumb model is defined by the TB,MC command. Static analysis is first performed with global acceleration loading along the Y-direction. The analysis is then restarted and solved with a tapered displacement load applied at edge OA to simulate the earth pressure problem. The ratio of to at the left edge OA is calculated using PATH operations and compared with the reference solution.

Results Comparison