风暴潮作用下黄河水下三角洲斜坡稳定性研究

斜坡失稳是河口海岸环境中典型的灾害地质现象之一,其对采油平台、海底管线和电缆的危害性是巨大的。本文以黄河三角洲地区埕岛油田典型海域为研究对象,通过地球物理探测和工程地质钻探获取了10m深度范围内海底土体的分层情况和各土层的物理力学特征,利用GEO-SLOPE/W软件对其水下斜坡的稳定性进行了定量计算。结果显示,极端海况下,水下斜坡表层土体存在产生滑移破坏的可能。另外,对该区海底斜坡失稳的机理进行了探讨,认为风暴潮引起的巨浪是其主要诱因。

STABILITY ANALYSIS OF SLOPES IN THE SUBAQUEOUS DELTA OF THE YELLOW RIVER UNDER STORM WAVE LOADING

Slope instability is one of the most important geohazards to offshore structures.It can cause great damages to oil production platforms,pipelines and electric cables which are based on the seafloor.In this study,a typical sea area in Chengdao Oilfield in the subaqueous delta of the Yellow River is chosen as the study area.Geophysical prospecting and geotechnical drilling are processed to get the stratification and the mechanical characteristics of the soil within the upper 10 m depth.The stability of the slope in this area is calculated using GEO-SLOPE/W.It turns out that slope instability may occur in clayey silt in the surface of the seafloor.The potential failure modes are discussed.It is concluded that the large waves caused by storm tides are the dominating triggering sources.