某海域松散砂层钻探成孔问题的探讨

Discussion on Drilling Pore-forming of Maritime Loose Sand Layer

针对某港口工程海域松散砂层钻探成孔中,多次出现的塌孔和涌砂致使取土困难不能进行原位测试的问题,在实际操作中经过反复试验,采用加重泥浆护壁和投放粘土球等办法,增加钻孔孔底的压力和孔壁的泥皮厚度,使层压水不易向钻孔内渗流,并通过适当控制钻进速度最终解决了钻探成孔问题,保证了工程地质勘察资料的准确性、真实性。

Since holes collapse and sand gushing occur frequently during the drilling pore-forming of maritime loose sand layer in one port project, soil sampling is hard to be done, which results in the difficulty of in-situ test. In long trial, we adopt the method of weighing mud protection wall and throwing in clay ball, which increase the bottom pressure and mud wall thickness of the bore hole, and prevent the bore hole from the seepage of laminated water. In addition, by controlling the drilling velocity properly, we finally resolve the drilling pore-forming problem, which guarantees precision and reality of the geologic investigation data.