论文部分内容阅读
我国海域普遍分布有迭层土,由于结构的特殊性,对于其性质的准确把握,直接影响到海洋工程诸如打桩、钻井船插深等问题预测的准确性,关系到海洋工程建设的安全。现场进行孔压静力触探CPTU试验以及室内试验,分析我国南海海域迭层土的物理、力学性质的特点,对迭层土抗剪强度值的确定进行探讨。CPTU试验数据显示,迭层土的物理力学性质与单一土层具有较明显的差异;由于迭层土中砂层的存在,室内三轴不排水剪切试验(UU试验)确定的不排水强度明显偏低,是CPTU确定的不排水抗剪强度的下限值。CPTU的结果可以较好地反映了迭层土的特点,根据CPTU试验结果得到的摩阻比变化范围较大,在0~8之间远大于一般的砂土或黏土的变化范围,摩阻比与修正端阻之间的关系可用双曲线近似表示。建议进行静力分析时,迭层土不排水抗剪强度参数选取应参考CPTU试验结果。
Due to the particularity of the structure, the accurate grasping of its properties has a direct impact on the accuracy of the prediction of offshore engineering such as piling and penetration of drilling vessels, which is related to the safety of marine engineering construction. The CPTU test and the in-house test were conducted on site to analyze the physical and mechanical properties of the laminated soil in the South China Sea, and the determination of the shear strength of the laminated soil was discussed. CPTU test data show that the physical and mechanical properties of laminated soil have obvious differences with that of single soil layer. Due to the presence of sand layer in the layered soil, the undrained strength determined by UU test of indoor three-axis undrained shear test Low, is the lower limit of undrained shear strength determined by CPTU. The results of CPTU can better reflect the characteristics of laminated soil. According to the results of CPTU test, the range of friction-resistance ratio is large, ranging from 0 to 8 much larger than that of common sand or clay. The friction ratio And the relationship between the revised end of resistance can be hyperbolic approximation. Proposed static analysis, the selection of undrained shear strength of laminated soil should refer to the CPTU test results.