【摘要】 隧道施工容易破坏岩溶裂隙水流通通道,导致局部性的地下水位急剧下降和地表水的干涸,严重影响隧道周围居民生活.地质雷达是隧道工程中常用的地球物理仪器,当应用该仪器进行勘探时,如果勘探表层存在密集钢筋干扰就会导致深部病害难以识别.工程中应用地质雷达在隧道内探测隧道路面地下水分布时,由于隧道路面表层存在的钢筋网的影响,导致雷达数据剖面深部振幅较小,异常难以识别.本文首先进行了地质雷达二维有限差分数值模拟方法,研究了表层密集钢筋对深部含水裂隙通道识别造成的影响情况,并通过对模拟数据进行偏移成像和希尔伯特振幅变换处理,压制了表层强反射的干扰,研究了含水裂隙通道的典型异常特征;最后以郴宁高速公路某隧道为例,应用本文提出的方法,压制了隧底路面下密集钢筋的影响,准确探测出了含水裂隙通道的空间分布情况,证明本文提出的方法的可行性.更多还原

【Abstract】 he karst fissure water channels will be easily destroyed in the construction of tunnel,and it severely affects the everyday life of the local residents with the localized sharp declining of groundwater and the drying up of surface water.Ground-penetrating radar(GPR) is a geophysical instrument which is commonly used in the tunnel engineering.It is difficult to identify the deep defects when the steels are densely covered on the road surface of the tunnel when we using the GPR to detect the abnormalities.In the engineering applications,when using GPR to detect the distribution of the underground water under the tunnel road,it is hard to identify the abnormalities because the amplitude of radar data which is in the deep department of the section becomes very small, and this due to the existence of the steel mesh which lies on the surface of the tunnel road.In this paper,with the simulation method of two-dimensional finite difference numerical,firstly researched the impacts of the densely covered steels to the identification of the deep karst fissure water channel.Then processed the simulated data,the strong surface reflex interference is suppressed with the migration and Hilbert transform methods and studied the typical abnormal characteristics of the karst fissure water channels.Finally,take a tunnel of Chen-Ning Expressway for example,the impacts of densely covered steel which under the road surface of the tunnel is suppressed with the methods of the migration and Hilbert transform proposed in this paper,the spatial distribution of karst fissure water channels are detected accurately,and this proved that the method which was proposed in this paper is feasible.更多还原