南黄海铁板砂地层插桩分析及应对

Analysis and Countermeasures of Pile Insertion in the Iron Plate Sand Stratum of the South Yellow Sea

南黄海盆地存在海底地层岩性为中密的灰色粉砂,砂颗粒级配均匀,孔隙水饱和,俗称铁板砂地层。自升式钻井平台在该种地层插桩时桩腿难以入泥,且入泥深度较小,另外随着平台自身及环境载荷变化,桩腿会发生下沉,严重影响作业及平台自身安全。通过对南黄海某探井在作业海区海底铁板砂地层的插桩深度浅、作业期间桩腿下沉情况进行原因分析,提出针对性措施及建议,为后续类似井作业提供参考借鉴。

The lithology of the South Yellow Sea Basin is medium-dense gray silt,the sand particles are evenly graded,and the pore water is saturated,commonly known as the iron plate sand stratum.When the jack-up drilling platform is inserted into the stratum,the pile legs are difficult to enter the mud,and the depth of entering mud is small.In addition,with the change of the platform and the environmental load,the pile legs will sink,which seriously affects the safety of the operation and the platform.Through the analysis of reasons for the shallow depth of pile insertion and the subsidence of pile legs during the operation of an exploration well in the iron plate sand stratum of the South Yellow Sea,the measures and suggestions are proposed to provide references for the subsequent similar well operations.