负压条件下的地下水位测试装置及试验研究

摘要

针对现有地下水位测试技术在负压条件下测试不可靠的问题,研发了一套新型地下水位测试装置.该装置主要依靠摄像技术,具体由摄像头把负压条件下地下水位位置传输至图像接收端口,从而实现PC端可视读数.通过现场试验进行新技术与常规(敞口式)技术对比,研究了加固区内地下水位变化以及单个排水板周围地下水位变化规律.试验结果表明,新测试方法比常规技术更直观可靠地获得地下水位位置;加固区内的地下水位在负压加固初期(0～15 d)下降迅速,中期缓慢,后期趋于稳定;在单排水板周围,紧贴排水板处地下水位下降迅速,距离排水板0.5 m和0.7 m处下降较慢,最终形成漏斗状地下水位面;在整个加固区内,形成以单排水板为单元组成的漏斗状水位坡面,其中加固区中心为漏斗的底部.%An apparatus for measuring groundwater level has been designed to solve the problem that the preceding technological tests have difficulty under the negative pressure.This apparatus mainly relies on the photography technology,specifically through the camera directly past the groundwater level to an image receive port,then implementation of visual reading on the PC interface.Comparing the new and conventional (open type) technologies in the field tests,we studied the groundwater level variation inside the improvement zone and the surrounding area of a single drainage board reinforced zone.The results demonstrate that the new method is more intuitive than conventional technology to obtain factual and reliable groundwater level under negative pressure condition.During the vacuum preloading,the groundwater level decline rapidly in the initial stage (0～15 d),slowly in the medium and later stabilize.Around an individual drainage board,the variation of the groundwater level is a rapid decline in close to the drainage board,and is dropping slowly at 0.5 m and 0.7 m far from the drainage board,and finally becomes a funnel-shape surface of the groundwater level.Throughout the improvement area,the groundwater level is a funnel-shaped that composed of single drainage board,and the bottom of the funnel in the improvement area center.