Experimental and Numerical Analysis of Pile–Rock Interaction Characteristics of Steel Pipe Piles Penetrating into Coral Reef Limestone

In order to study the characteristics of pile–rock action steel pipe driven pile in coral reef limestone stratum, at China–Maldives Friendship Bridge site was selected carry out indoor physical and model tests with red sandstone as control group. The test outcomes indicate following: (1) when substantial deformation is permitted, has a considerable strength dispersion, low post-peak stress decrease rate, high residual strength, roughly 30% peak strength; (2) penetrates limestone, top load shows an obvious sawtooth shape, increase penetration depth, end high-porosity rock sample gradually decreases, low-porosity increases; (3) penetrated, strain value about twice that same position from pile. These findings porosity heterogeneity cementation make extrusion effect during piling significantly less than sandstone. addition, process numerically simulated using four-dimensional discrete spring method based on multi-body damage criterion. numerical simulation results further demonstrate pile-side fragmentation primary reason for lower bearing capacity piles stratums. This provides novel approach studying mechanical properties limestone. can serve guide design construction stratum.