坦桑尼亚某海湾管道工程海岸滑坡与防治

Coast Landslide and Control of a Gulf Pipeline Project in Tanzania

海岸滑坡和侵蚀的存在严重影响着管道工程的稳定性,根据多种地球物理勘察手段的识别,查明坦桑尼亚某海湾管道路由区有海岸滑坡、海岸侵蚀、砂土液化和软土震陷等不良地质作用。结合地形、地层、海洋水动力条件等因素,对滑动机理进行综合分析;在分别考虑潮位和不考虑潮位作用下,采用极限平衡理论结合数值模拟分析进行稳定性评价。研究得出:海岸滑坡是第三层淤泥质粉质黏土层液化所导致的,是滑坡向海岸后退式(牵引)滑动的结果。基于滑动原因给出管道改线和防治措施,对海岸滑坡的定性评价有很好的补充,为海岸滑坡的整治提供了科学依据。

Coastal landslide and erosion have a serious impact on the stability of pipeline engineering. Based on the identification of various geophysical prospecting methods,the geological effects of coastal landslide,coastal erosion,sand liquefaction and soft soil seismic subsidence in Tanzania pipeline routing area are identified. The sliding mechanism is comprehensively analyzed by combining the factors such as topography,stratum and ocean water dynamic conditions,and the stability evaluation is conducted using the limit equilibrium theory and the numerical simulation. The results showed that the coastal landslide sliding was caused by the liquefaction of the third layers of muddy silty clay layer. It is the result of the sliding of the landslide to the coast. Based on the sliding cause,the prevention and cure measures of the pipeline are given,which provide a scientific basis for the improvement of the coastal landslide.