heaving sand造句

• Deep foundation trenches in shallow rocks in some cities along a seashore like qingdao , dalian , zhuhai things like that often need to be dug or exploded into hard rock , there are heaving sand , soft soil , groundwater upon it
  青岛、大连、珠海等基岩埋深浅的沿海地区深基坑经常需要挖至基岩甚至需要爆破开挖，基岩以上又有流砂、软土、地下水等。