基于灰色关联分析回归天津市区土体剪切波速

REGRESSION OF SOIL SHEAR WAVE VELOCITY IN TIANJIN URBAN REGION BASED ON GRAY CORRELATIVE ANALYSIS

利用天津市78个钻孔2 212组不同岩土体的剪切波速数据,分析天津地区土层剪切波速随土层深度、岩土类型等影响因素的变化规律,利用灰色关联分析方法研究上述影响因素与天津地区土层剪切波速之间的相关性,获得该区土层剪切波速各影响因素的灰色关联排序,继而得到区分岩土类型的剪切波速回归公式,利用所得公式对实际钻孔不同深度剪切波速进行预测,并基于实测结果对预测结果进行分析。在天津地区,应综合利用岩土类型和土层深度对剪切波速进行评价。不同岩土类型、剪切波速与深度的相关性大小存在较为明显的差异,其中粘土的剪切波速和深度之间的相关性最强。同等深度条件下,由粘土到细砂粒径逐渐增大,其相应的剪切波速也逐渐增大。各类主要岩土体剪切波速与埋深之间的相关关系中多项式模型拟合精度最高,可用于天津市区主要土体剪切波速计算工作。

In this paper,the shear wave velocity data of 2 212 sets of different soils of 78 drilling wells in Tianjin urban region were used to analyze the variation of shear wave velocity with depth and soil type, the gray correlative analysis method was used to analyze the correlation between above in- fluencing factors and shear wave velocity, and the gray correlative sequence of each influencing factor was obtained, then the regression formulas of shear wave velocity were obtained in the case of consid- ering soil types, which were used to estimate the shear wave velocity of different depths in the actual drilling, and the estimated results were analyzed basing measured results. The results show that, the shear wave velocity should be evaluated by comprehensive utilization of soil types and soil depth. The correlation between shear wave velocity and soil depth of different soil types had an obvious differ- ence, in which the correlations of clay was the best. At the same time, the particle size gradually in- creased from tile clay to the fine sand, the corresponding shear wave velocity gradually increased. The fitting accuracy of polynomial model were the best and soil depth of different soil types, which can be ferent soil types in Tianjin region. in all relationships between shear wave velocity used to calculate the shear wave velocity of dif-ferent soil types in Tianjin region.