Optimization for U-Shaped Steel Support in Deep Tunnels under Coupled Static-Dynamic Loading

Figure 11

The deformation of various contact area ratios. The black curve represents the ratio of contact area of 1/4, the red curve represents the ratio of contact area of 1/3, the blue curve represents the ratio of contact area of 1/2, the pink curve represents the ratio of contact area of 2/3, the green curve represents the ratio of contact area of 3/4, and the gray curve represents complete contact.