渤海土类动力非线性参数及合理性

针对当前我国土动力学特性理论研究大多集中在陆地,而海域典型土类的动力特征尚无系统性研究成果的问题,收集整理了渤海海域近40个海洋石油平台地震安全性评价报告中动三轴试验取得的372组土体动力非线性参数数据,给出了渤海海域不同土类不同埋深的动剪切模量比和阻尼比的统计平均值.以典型场地为基础,对比分析了所给出的统计平均值与规范值、推荐值对场地地震动参数的影响,论证了所给出的平均值的合理性.研究结果表明,与规范值、推荐值对比,所给出的统计平均值与实测值的地震反应分析结果吻合程度高,合理可信,为渤海场地土动力学参数实测数据不足情况下的必要补充.

Dynamic nonlinear parameters of soil in the Bohai Sea and their rationality

In recent years,the theoretical studies of soil dynamic characteristics have been mostly concentrated on land,and there has been no systematic research of dynamic characteristics of the typical soil types on the seafloor.The dynamic nonlinear parameters of 372 groups of soil samples were collected,and were tested by dynamic tri-axial tests in about 40 of the seismic safety evaluation reports of ocean platforms in the Bohai Sea.The dynamic shear modulus ratios and the damping ratios of different types of soils with different depths on the Bohai seafloor were calculated and their statistical mean values were obtained.Based on two typical sites,the influences of the statistical mean values in this paper,standard values in the code DB001-94,and the recommended values by YUAN X.M.(2000) on seismic ground parameters were compared and analyzed.The rationality of the statistical mean values was demonstrated.The results indicate that the seismic response results using the statistical mean values are closer to the results of using the real test values than the results of using the values in the code and the recommended values.The statistical mean values are believable,and they are necessary in the case that the tested soil dynamic parameters are not enough at the Bohai Sea sites.