微差爆破模拟天然地震的数值分析与效果评价  

Numerical analysis and evaluation of simulation of nature earthquake by millisecond blasting technique

作　　者：张智超[1,2] 陈育民[1,2] 刘汉龙[1,2] 

机构地区：[1]河海大学岩土力学与堤坝工程教育部重点实验室,南京210098 [2]河海大学土木与交通学院,南京210098

出　　处：《岩土力学》2013年第1期265-274,共10页Rock and Soil Mechanics

基　　金：国家杰出青年科学基金项目(No.50825901);国家自然科学基金项目(No.50909040)

摘　　要：微差爆破可以创造出与天然地震相类似的振动环境。为了更好地对爆破模拟天然地震进行研究和评价,在LS-DYNA软件框架内,建立了适合于爆炸荷载作用下土体动力分析的实用模型,对原位土体场地爆破地震动试验进行了全尺寸数值模拟,并将模拟结果与现场实测数据进行比较分析,验证数值计算的准确性。计算结果表明,模拟得到的场地质点加速度-时程与实测数据比较吻合,因此,可以预先利用数值手段为试验方案设计提供指导;同时,数值模拟还总结了现场试验中未得到的场地压力变化规律和振动规律,分析了爆破地震动与天然地震的异同,丰富了爆破地震动的研究,表明利用爆破手段能够近似地模拟天然地震,为微差爆破模拟天然地震的研究工作提供了经济、简便而实用的方法。Millisecond blasting can create vibration environment similar to that induced by a natural earthquake.In order to better study and evaluate the simulation of natural earthquake by means of blasting method,a constitutive model which can well describe the dynamic property of soil under blasting load is built in the frame of LS-DYNA;meanwhile,the full-scale numerical simulation is implemented for an in-situ test of blast-induced ground motion in a soil field;and the simulated results are compared with test data,which validates the accuracy of numerical method.The analysis results reveal that the simulated acceleration time histories are approximate to the recorded results in the field test,so as to indicate that the numerical method can provide useful instructions beforehand for the in-situ blasting tests;furthermore,the pressure developments that haven＇t been recorded in the in-situ test are also obtained as well as analyzed;and the similarities and differences between blast-induced ground motion and nature earthquake are discussed too,which enriches the research on the blast-induced ground motion.The results show certain degree of effectiveness of simulating natural earthquake by blasting test,so as to supply a simple,effective and economic numerical method for simulating natural earthquake by means of millisecond blasting test.

关 键 词：微差爆破 地震 LS-DYNA 加速度 效果评价 

分 类 号：TU443[建筑科学—岩土工程]