Abstract: In order to investigate the compacting effects caused by the penetration of pre-stressed high-strength concrete (PHC) pipe pile group on surrounding engineering environment, we carried out on-site monitoring on the excess pore water pressure and deep soil displacement in Zhumadian. Results show that the excess pore water pressure approximately linearly reduces as the distance to the pile group boundary increases, and the radius of excess pore water pressure’s influence increases with depth, the maximum radius of influence is about 29 times the diameter of the pile. The surface soil displacement is large, and the displacement decreases with the depth to almost zero until the pile end. The horizontal displacement is significantly affected by the relief grooves, and the effective impact depth is approximately two times its depth.

Key words: pile group, horizontal displacement, excess pore water pressure, environmental monitoring, PHC pipe piles