地面物探在岩溶地基工程勘察中的应用——以桂林某花园综合楼为例

APPLICATION OF THE GROUND PHYSICAL EXPLORATION IN KARST FOUNDATION ENGINEERING PROSPECTING——A Case Study from a Comprehensive Building in a Garden of Guilin

岩溶地区工程建筑地基的地质情况比较复杂,存在土洞、软土等工程隐患。常规工程勘察手段,由于其自身的局限性,很难一一查清这些隐患的分布特征。地面物探是一种较为省时省力的工程辅助勘探方法。但物探方法有多种,在选用时,必须根据场地条件、探测目标、方法性能及工作成本等来综合考虑,选择适用的方法(或方法组合),才有可能取得令人满意的探测效果。桂林某花园综合楼地基主要以红粘土为主,软土、土洞发育,红粘土之下,桂林组灰岩表面起伏强烈,溶洞发育。根据场地地质特征及基坑开挖特点,本勘察采取浅层地震折射、反射波法,并配合高密度电阻率测量,较好地查明了场地软土和土洞的分布位置,为综合楼的地基处理提供了可靠的地质依据。

The geological condition of engineering foundation in karst region is relatively complicated. Hidden troubles, such as soil hole, soft soil, exist in the engineering foundations. Normal geologic prospecting methods, limited by the function of itself, may not be used to make clearly those hidden troubles easily. However, ground physical exploration is an economical measure. There are many kinds of physical exploration methods,but only suitable ways being chosen and used according to site settings,detecting objectives and etc. can result in good results. The foundation of the comprehensive building in a certain garden in Guilin mainly composed of red clay with hole development in it. Under the red clay, the limestone surface rises and falls strongly and karst are well developed. According to the characteristics of the geologic condition and the pit of the foundation, the shallow refract, reflect method and coordination of the resistivity method of high density, are used. The location of the soft clay and the hole in it was fixed satisfactorily, which provided reliable geologic basis for the treatment of the building foundation.