The construction of pile foundation is difficult for the growth of karren, slot, eagle nib, soil hole, karst etc, and the intensity undulation of rockbed in karst region.

• 岩溶区因溶沟、溶槽、石芽、鹰咀、溶洞、土洞等发育，基岩面起伏强烈，给岩溶区桩基础施工带来较大困难。