跨孔探测技术在深圳地铁3号线岩溶勘察中的应用

Application of Cross Hole Detection Technology in Subway Karst Exploration of Shenzhen Metro Line 3

岩溶地质条件对地铁建设影响极为不利,当隧道穿越岩溶发育区时,常引起突水、塌陷、地面沉陷及盾构机栽头等事故。采用物探技术辅助岩溶钻探地质勘察已越来越受到重视。该文以深圳地铁3号线四期工程探测效果为例,主要介绍了跨孔弹性波CT方法和跨孔超高密度电阻率法原理及技术流程,对两种方法进行了分析和对比,从探测目标体大小及精度上,提出采用跨孔弹性波CT与超高密度电阻率法综合探测手段进行地铁岩溶探查,可起到较好的互补作用,为隧道岩溶勘察提供了可靠的科学依据。

The karst geological conditions have a very adverse impact on subway construction.When the tunnel passes through the karst development area,it often causes the water inrush,collapse,ground subsidence and shield head accidents.More and more attention has been paid to using geophysical technology to assist karst drilling geological survey.Taking the detection effect of phase IV of the Project of Shenzhen Metro Line 3 as an example,this paper mainly introduces the principle and technical process of cross hole elastic wave CT method and cross hole ultra-high density resistivity method,and analyzes and compares the two methods.In terms of the size and accuracy of the detection target,the comprehensive detection method of cross hole elastic wave CT and ultra-high density resistivity method for subway karst exploration is proposed,which can play a better complementary role and provide a reliable scientific basis for tunnel karst exploration.