论文部分内容阅读
我队先后在渭河两岸第四纪黄土塬区承担农田供水水文地质勘探，每当抽水试验结束，试验管起拔十分困难。我队曾用过：（1）强力起拔；（2）爆破起拔；（3）用冲击铲松动起拔；（4）加大钻孔口径；（5）反、割等方法起拔试验管。但处理时间长，代价高，还经常出现因塌孔被迫丢管。尤其在分层抽水钻孔，由于下段试验管不能如数起拔，影响到上部试段的试验，最终重新补打副孔。后来使用分级套接起下试验管方法，分别在大荔、合阳、兰田、韩城等县的黄土塬区进行了九孔试验。又在华阴、潼关等县的洪积扇与冲积地层进行了三孔试验，效果均良好，此法已成为我队起下试验管的主要方法。现将基本情况介绍如下：
Our team successively carried out hydrogeological exploration of farmland water supply in Quaternary Loess Plateau on both sides of the Weihe River. When the pumping test was completed, it was very difficult to test the pipe. Our team has used: (1) strong lifting; (2) blasting and lifting; (3) loosening and pulling with an impact shovel; (4) increasing the borehole diameter; tube. However, the processing time is long, the cost is high, and it is often caused by the collapse of the hole was forced to lose control. Especially in the stratified pumping boreholes, because the lower test tube cannot be lifted up, affecting the test of the upper test section, the auxiliary borehole is finally refilled. Later, a test method was used to pull down the test tube, and a nine hole test was conducted in the loess area of Daxie, Heyang, Lantian, and Hancheng counties. In addition, three-hole tests have been carried out in the alluvial fan and alluvial formations in Huayin and Shaoguan counties, and the results have been good. This method has become the main method for our team to test tubes. The basic situation is now described as follows: