Abstract:The pile foundations with man-made hole in Laboratorial Building of Zhenguang Middle School are used,and part piles that cannot meet the requirements of design are founded to be settled on intensely weathered zone after testing. The supplementary investigations of engineering geology show that the mechanical parameters of soil and rock,and bearing capacity are improper for the design through calculation of pile foundations. So,grouting is employed for the cases,where the bearing capacity of pile foundation can satisfy the requirements of design. The observation settlement shows that the grounding effects can be accepted. The achieved results that the grouting technique is adequate for pile foundation treatment when the pile end is located on intensely weathered zone.