陕西关中平原地区V_(s30)估算模型研究  

Estimation Model of V_(s30)in Shaanxi Guanzhong Plains

作　　者：张炜超 孙昱 田勤虎[1] 任浩 韶丹[1] 阮仕琦 ZHANG Weichao;SUN Yu;TIAN Qinhu;REN Hao;SHAO Dan;RUAN Shiqi(Shaanxi Earthquake Administration,Xi’an 710068)

机构地区：[1]陕西省地震局,西安710068

出　　处：《土工基础》2022年第5期760-764,共5页Soil Engineering and Foundation

基　　金：陕西省地震局启航与创新基金(QC202019)。

摘　　要：地表以下30 m深度的平均剪切波速(V_(s30))是评价场地条件及场地地震影响的一个重要参数,但我国存在大量深度小于30 m的钻孔数据,无法直接计算得到V_(s30),阻碍了我国借鉴和使用国外与V_(s30)相关的研究成果。基于陕西关中平原4城市590个孔深大于30 m的钻孔数据,采用常速度外推模型、速度梯度模型、双深度参数外推模型开展本地化V_(s30)估算模型研究,结果发现:常速度外推模型更适用于钻孔深度超过15 m时估算V_(s30)值;当钻孔的波速资料深度小于15 m且钻孔数据量大时,速度梯度外推模型中的线性模型更适用于估算V_(s30)值;考虑到双深度参数外推模型不需要通过大量钻孔数据统计得到经验关系且估算总误差较小,该模型适用于整个深度范围(10~28 m),应用性更强。The average shear wave velocity to a depth of 30 m below the ground surface(V_(s30))is an important parameter for evaluating the site seismic condition and the site earthquake response and is widely used worldwide.But there are many bore hole data with depth less than 30 m,and these bore hole data cannot be directly used to evaluate the V_(s30)so that the correlated research results which include the parameter of V_(s30)might not be directly referenced.Based on the data from 590 bore holes with depth greater than 30 m in Guanzhong plain of Shaanxi Province,the test data were evaluated by using three models,namely,the bottom layer constant velocity model,the velocity gradient model and the extrapolation model with the travel-time averaged shear-wave velocities at two different depths.Throughout this study the V_(s30)estimation model can be therefore localized.The results show that,the constant velocity extrapolation model is more suitable for estimating the V_(s30)value when the bore hole depth exceeds 15 m;when the depth of the bore hole is less than 15 m and the amount of borehole data is large,the linear model in the velocity gradient extrapolation model is more appropriate for estimating the V_(s30)value.Considering that the extrapolation model with the travel-time averaged shear-wave velocities at two different depths does not need any regression analysis to derive empirical relations from a large number of data and the total estimation error is small,this model is appropriate for the entire depth range(10-28 m)and is more applicable.

关 键 词：关中平原 平均剪切波速 V_(s30)外推模型 适用性 

分 类 号：TU435[建筑科学—岩土工程]