一种场地VS30经验估计最佳模型的选用方法——以新疆地区为例
米欣雪1,2,张雨婷1,2,任叶飞1,2,王宏伟1,2,温瑞智1,2

(1.中国地震局工程力学研究所 地震工程与工程振动重点实验室,黑龙江 哈尔滨 150080; 2.地震灾害防治应急管理部重点实验室,黑龙江 哈尔滨 150080)

地质年代; VS30; 模型评估; 对数正态检验

A method for selecting the optimal model of VS30 empirical estimation: A case study of Xinjiang Region
MI Xinxue1,2,ZHANG Yuting1,2,REN Yefei1,2,WANG Hongwei1,2,WEN Ruizhi1,2

(1.Key Laboratory of Earthquake Engineering and Engineering Vibration, Institute of Engineering Mechanics, China Earthquake Administration, Harbin 150080, China; 2.Key Laboratory of Earthquake Disaster Mitigation,Ministry of Emergency Management,Harbin 150080, China)

geological age; VS30; model evaluation; lognormal test

DOI: 10.15986/j.1006-7930.2023.02.018

备注

在计算工程场地的VS30值时常由于钻孔深度的限制需要依赖经验模型进行外推估计,大量学者进行了相关经验模型的研究,不同方法之间计算结果存在差异且有些方法具有区域依赖性,如何选用一个最适用于本地区的模型至今未有研究给出合理方法.本文首先简要介绍了目前常用的5种经验外推模型,以新疆地区为例,利用钻孔深度超过30 m的工程钻孔数据计算各模型在不同深度处的回归系数; 接下来,利用区域地质图划分出6个地质单元,基于相同地质条件下场地钻孔的岩性剖面具有相似分布的假设,通过对不同单元下的钻孔数据进行对数正态性检验,判断5种经验模型在不同地质单元下的适用性.得到以下结果:(1)地质年代为二叠纪及二叠纪之前的工程场地在外推模型选取上宜采用翠川三郎及野木淑裕提出的双剪切参数模型(MN15);(2)中生代场地对非线性(二次)对数外推模型表现出最显著的适用性(BEA11);(3)新生代场地采用非线性对数外推模型计算结果明显优于其它模型(BEA11).研究结果可为模型的潜在使用者提供有价值的辅助信息,也可以为我国其他地区VS30外推经验模型的开发研究提供理论参考.
Due to the limitation of the drilling depth, it is necessary to rely on the empirical model for extrapolation estimation while calculating the VS30 value of the engineering site.A large number of professors have conducted research on relevant empirical models.The results of different methods are different and some methods have regional dependence.How to choose a model that is most suitable for the region has not yet been studied to give a reasonable method.In this paper, five commonly used empirical extrapolation models are briefly introduced firstly, and at the same time taking Xinjiang area as an example, the regression coefficients of each model at different depths are calculated by using engineering borehole data with drilling depth more than 30 m.Next, the regional geological map is used to divide 6 geological units.Based on the assumption that the lithological profiles of the site drilling under the same geological conditions have similar distributions, the lognormality test of the drilling data under different units is used to determine the applicability of the five empirical models under different geological units.The following results are obtained:(1)the double shear parameter model proposed by SaburoTsuikawa and ShuyuNogi(MN15)should be used in the selection of the extrapolation model of the engineering site with geological age of Permian and pre-Permian periods;(2)Mesozoic sites show the most significant applicability to nonlinear(quadratic)logarithmic extrapolation models(BEA11);(3)the calculation results of the nonlinear logarithmic extrapolation model of the Cenozoic site are significantly better than those of other models(BEA11).The research results can provide valuable auxiliary information for potential users of the model, and can also provide theoretical reference for the development and research of VS30 extrapolated empirical models in other regions of China.