上海东海大桥大乌龟近岛段工程地质评价

Study on Engineering Geology for Dawugui Island Section of Donghai Bridge

针对在上海东海大桥施工勘察中存在的主要工程地质问题,以大乌龟近岛段PM451墩为例,根据钻探成果和高分辨率地震资料,对桥墩位处岩层分布特性及岩面起伏变化状况,强风化岩层、球状风化体(孤石)、断层破碎带等不良地质现象进行了分析,并运用现代计算机技术,绘制了PM451桥墩处海水面下基岩起伏面立体图,明确了嵌岩桩的合理持力层顶面标高和嵌岩桩承载力,为实际工作提供了科学依据。

There are many geo-technical problems in the survey of Donghai bridges such as PM451 near Dawugui Island. On the basis of drilling and high distinguishing rate of seismic data, we pointed out some bad geologic phenomena of bridge foundation in this paper, for example, slope stability, different surface of bedrock, strong weathered rock and fault, etc. We also protracted cubic chart of surface of rock and computed micro-weathered rock and computed bearing capability for single embedded pile on PM451 by computer.