# Dynamic Response of Non-Yielding Wall Supporting Over-Consolidated Sand
## 4 Results
### Effect of Wall Panel Modulus of Elasticity  
The influence of the elastic modulus of the non-yielding wall is investigated by applying the base excitation to models with varying wall stiffnesses. The considered wall modulus values are E\({}_{\rm w}\) = 2.1, 21, 34, and 47 GPa, which correspond to wood, low-strength concrete, medium-strength concrete, and high-strength concrete, respectively. The concrete non-yielding walls in this study may represent some types of basement walls and bridge abutments. The wooden walls in this study may represent braced excavation panels that are used with medium- to shallow-depth excavations. Figure 20 depicts the variation in incremental dynamic deflections at mid-height with different values of wall panel elastic modulus. As expected, the maximum incremental deflection is highest in the case of a wood wall, in which the deflection was more than four times that of the average-strength concrete. In the case of concrete wall panels, increasing the elastic modulus within the typical range of concrete decreased the deflection increments. Increasing the wall rigidity from that  
Figure 18: Variation in maximum, minimum, and residual lateral earth forces with backfill OCR. of the low-strength concrete wall by 62% and 114% resulted in a maximum incremental deflection decrease of 29% and 44%, respectively. The residual incremental deflections were found to be significantly lower than the maximum incremental deflections. In the cases of medium-strength and high-strength concrete panels, the residual incremental deflections were almost zero. Maximum and residual total earth pressures due to base excitation are shown in Figure 21 for varying wall elastic modulus values. Figure 21a indicates that within the top 1/3 H, the maximum earth pressures increased significantly above the static values in all panel types. Moreover, in this region, the magnitude and distribution of the maximum pressure were found to be similar regardless of the panel material. Within the bottom 2/3 H, the maximum pressure on the wood panel was lower than that on the concrete panels. The maximum pressure behind all concrete panels was comparable within the bottom 2/3 H. Nevertheless, panels of higher-strength concrete experienced slightly larger pressures than panels of lower-strength concrete. Figure 21b shows that the walls with high rigidities (i.e., concrete) did not develop significant residual pressures at the end of the excitation. The case of the wooden panel is different, where the pressure is larger than the static case in some locations and lower in others. This suggests that consideration of residual stresses is more critical in a non-yielding wall with lower rigidity. Figure 19: Variation in maximum, minimum, and residual resultant elevation with backfill OCR. Figure 20: Variation in maximum and residual lateral wall deflection (mid-height) with wall elastic modulus. Maximum and residual total earth forces acting on the wall due to base shaking at varying wall elastic moduli are shown in Figure 22. Forces developed in static condition are shown for comparison. The figure shows that a significant increase in maximum total force occurred when the wall material was changed from wood to concrete. The larger forces in the concrete walls may be attributed to their lateral dynamic deflections (\(\Delta\)x), which are lower than the case of a wood panel (Figure 20). Within the concrete cases, increasing the wall elastic modulus had a limited impact on the maximum total forces. A slight increase in maximum force was observed when higher-strength concrete was used. The dynamic force increment was almost unaffected when different concrete strengths were used. Residual total forces increased when the wood panel was replaced by concrete panels. However, medium-strength and high-strength concrete panels experienced lower residual total forces than the low-strength concrete panels. The residual dynamic increment decreased as the panel elastic modulus decreased.