对气压、降雨等附加应力对井水位影响枧理的理论分析

本文运用弹性力学中关于均布荷载下半无限大弹性空间的应力解,对气压效应、降雨效应等进行机理分析,改进了前人提出的气压系数、降雨系数的理论计算公式。通过计算从理论上说明气压系数、降雨系数不仅与含水层本身性质有关,还与气压变化范围、降雨面积大小、承压井含水层埋深有关,并证明了两系数之和为1。本文还以苏07井为例,分析计算了地表水体涨落对井水位的干扰,结果与他人用二元回归方法所得的结果基本相符。

A THEORETICAL ANALYSIS OF MECHANISM OF DISTURBANCE OF WELL-WATER LEVEL CAUSED BY ADDITIONAL STRESS FROM AIR PRESSURE AND RAIN FALL

The additional stress which is caused either by air pressure and rain fall (The phenomena are defined as air pressure effect and rain effect respectively), or by rise and fall of surface water (such as river, lake etc.) can disturb water level of pressure well. In this paper, the solution of elastic half-space is used to analyse the pressure effect and rain effect. The pressure coefficient by J. Bear is modified and meanwhile the rain coefficient is proposed. Through calculation, we find that air pressure coefficient and rain coefficient are related not only to the behavior of aquifer, but also to the range of pressure variation, area of raining and the depth of pressure aquifer. Some facts of observation have been proposed that the sum of the two coefficients equals unity which is also proved in this paper. Taking Su-07 well as an example, we analyse the disturbance caused by rise and fall of the surface water, and the results of calculation is nearly keeping with the results which are got from the calculation of regression analysis.