3.3.3 Effect of wall stiffness

Diaphragm walls ranging from 0.6 m to 1.5 m thick，which represent an almost 15 times increase in wall stiffness（EI），were studied.Strut forces derived indicate a wall stiffness dependency.The greater the wall stiffness is，the larger the strut forces are.The phenomenon is believed to be linked to the arching effect induced by wall displacement.Stronger arching effect associating the larger displacement of thinner walls reduces the corresponding strut forces.It is noted that the highest strut force exceedance ratio is approximately 2.5 at the S3 level，with the rest falling generally below 2.0，while the forces of the inter⁃mediate strut levels experience higher exceedance rations，and the strut force intensity at the top and the bottom strut levels are conforming well with the reference APD.