静力触探技术在东海陆架工程勘察中的应用研究

Application of CPT in engineering survey of East China Sea continental shelf

通过对东海大陆架海底浅表层土样的静力触探参数进行统计分析,得到该区域细砂、粘土、淤泥质土和淤泥的静力触探统计值,建立了研究海区基于静力触探参数的土类判别图,可用于快速判定土的类别。根据静力触探参数,并应用经验公式估算了海底粘性土的抗剪强度和灵敏度,对估算公式经验系数选择进行了深入研究,提出在研究海区应用经验公式进行粘性土的抗剪强度和灵敏度估算时,经验系数Nkt和Ns分别取17和7所估算的结果和试验结果最为吻合。这些经验系数的确定对于利用静力触探技术对研究海区海底粘性土的工程特性做较全面的评价具有一定的意义。

Statistical analyses of the CPT parameters of the shallow layer soils from East China Sea continental shelf resulted in CPT statistical values of sandy soil, cohesive soil, soft soil and upon which soil class decision chart was built up for rapid soil classification in the study area. According to the CPT parameters, undrained shear strength and sensitivity of the cohesive soil were estimated with empirical formula and the selection of the empirical coefficients was studied thoroughly, which shows that in calculating the undrained shear strength and sensitivity of the cohesive soil, the results were the most identical with the experimental results when choosing 17 and 7 as Nkt and Ns. Determination of these empirical coefficients is importance for the evaluation of the engineering conditions of the cohesive soil in the studied area with CPT technology.