西南地区隧道工程条件下岩溶地下水系统变化特征分析

摘要

The construction of tunnels have an impact on the intrinsic characteristics of karst groundwater sys-tem,such as the fall of the water table or the loss of surface springs.In this paper,the variation characteristics of karst groundwater system in southwest China under tunnel engineering conditions is summarized and is divided into three categories according to the types(covered,uncovered and buried)of the aquifers,structural features, supply characteristics,the runoff ways of karst water and the engineering characteristics of tunnel construction. The paper also presents typical examples (Jinzhi river groundwater system)illustrating the analysis process that different tunnel plans produce different effects on karst groundwater system,and compares the results with avail-able tunnel seepage volume.As a result,the study can be used as a reference for the geological disaster preven-tion of tunnel water-bursting.%岩溶山区越岭长大隧道的施工不可避免地会使当地的岩溶水系统发生改变，如地下水水位的下降、地表泉点的漏失等。基于隧道工程对岩溶地下水系统边界条件、排泄状况等天然特征的影响，依据西南地区岩溶地下水系统主要特征及隧道工程特点，考虑隧道工程条件下影响岩溶地下水系统特征的主要因素，对岩溶类型（岩溶含水岩组的埋藏条件）、构造特征、补给特征、岩溶水径流方式与隧道工程特点相组合的模式下的岩溶地下水系统的变化进行特征分析，并将岩溶地下水系统的变化归纳为3种类型。据此，选择研究区金汁河地下水系统作为典型研究对象，假设3种隧道穿越方案，将不同隧道穿越方案下的岩溶地下水系统与天然岩溶地下水系统进行对比分析，归纳概述其变化特征，最后对各隧道方案下的涌水量及其涌水危险性进行初步预测及评价。