Abstract：The engineering geological conditions of Guangzhou—Foshan Lines are complicate，and the karsts are fully developed. The unknown engineering geological conditions are identified through detailed and additional investigation. The pile foundations are employed with punching boring，whose bearing strata are slightly weathered. Because there exist thick sand，fully developed faults and karst，and enriched groundwater，the karsts will have considerable effects on design and construction of engineering. If improper measurements are taken，they can improve the qualities of pile foundations. The series of treatment methods are adopted for the karst in design and construction. The achieved results show that it is available for considering the proposed methods in karst region.
