长江中下游特大桥主要工程地质问题的勘察与研究

INVESTIGATION AND RESEARCH ON SOME ENGINEERING GEOLOGICAL PROBLEMS IN CONSTRUCTION OF BRIDGES ACROSS THE CHANGJIANG RIVER

20世纪 90年代以来 ,长江中下游特大跨江公路专用桥建设开始起步 ,至今已有黄石、铜陵、江阴、武汉、南京等长江公路大桥建成通车 ,并有多座大桥正在建设和勘测设计 .在大桥建设中遇到了地震与断裂构造、软弱层带、极软岩、岩溶等复杂的工程地质问题 .在解决这些问题中除了采用常规的工程地质勘察和试验技术外 ,还进行了软岩流变试验、钻孔内彩色电视录像、原位承载力及压桩试验、桥基地质力学模型试验等技术和方法 ,取得了可靠的数据 ,为大桥设计提供了依据 ,并通过已建成大桥的实践得到了证明 .这些勘察研究的技术方法为长江中下游特大桥建设提供了经验 .

Since the 90s, 20th century, the construction of big traffic bridges across middle-lower reaches of the Changjiang River has stepped into fast development. So far, bridges in Huangshi, Tongling, Jiangyin, Wuhan, and Nanjing have been in transport service. Still, some bridges are under construction and design. Various engineering geological problems have occurred, such as fault, soft interlayers, extreme softrocks, karst caves, and so on. In addition to common methods of investigation and mechanical test, the rheology test of softrocks, color video recordings, the field bearing test, and the pier analogue simulating have been taken to deal with the problems. The practice has provided dependable data for bridge design, which has been proved successful in the construction of bridges, and will be of treasury experience for the future bridge construction in middle-lower reaches of the Changjiang River.