北京地区土层剪切波速与埋深之间的相关性分析

剪切波速是土体重要的动力学参数之一。以收集到的北京地区地震安全性评价报告中实测剪切波速资料为依据,进行统计分析;利用幂函数作为回归模型,给出该地区包括黏土、粉质黏土、粗中砂、粉细砂和粉土五种常见土类剪切波速与埋深之间关系的推荐模型;并和全国范围内常规土类的回归模型及《构筑物抗震设计规范(GB50190—2012)进行对比。利用两个不同场地实例对比验证了回归模型的可行性。结果表明:①区域内各常见土类(除人工填土外)剪切波速与埋深间存在联系,且离散程度随埋藏深度增大而增大;②推荐模型除Ⅱ类场地细砂土表现略差于刘模型外,其余土类均较为接近实测数据;③区域性对剪切波速与埋深之间的相关性存在影响。

Correlation analysis between shear wave velocity and buried depth of soil layer in Beijing area

Shear wave velocity was one of the important kinetic parameters of soil. Based on the measured shear wave velocity which collected from the seismic safety evaluation reports in Beijing area, the power function was chosen as the regression model to carry on the statistical analysis, A recommended model for the relationship between shear wave velocity and burial depth of five common soils (including clay, silty clay, coarse-medium sand, silty-fine sand and silt) in this area was given, after that, a model which was proposed by Liu and others was used to compare with the model in this paper, finally two different site examples were used to validate the regression model. The results show that: (1) There is a relationship between shear wave velocity and buried depth of common soils (except for artificial fill), and the degree of dispersion increases with the increase of burial depth; (2) except for the fine sand of the II category site, the results which are calculated by the recommended model give are close to those of Liu model; (3) the regional effects have an effect on the correlation between the shear are velocity and burying depth.