精确毫秒延时控制爆破地震反应谱特性研究  

Response Spectrum Research of Blasting Seismic Induced by Controlled Blasting with Precise Millisecond Delay

作　　者：何理[1] 钟冬望[1] 涂圣武[1] 操鹏 

机构地区：[1]武汉科技大学理学院,湖北武汉430065

出　　处：《金属矿山》2015年第10期11-17,共7页Metal Mine

基　　金：国家自然科学基金项目(编号:51174147);湖北省自然科学基金项目(编号:2012FFA135);武汉科技大学研究生创新基金项目(编号:JCX0017)

摘　　要：利用地震工程中应用较为成熟的反应谱理论对精确毫秒延时控制爆破地震进行研究,设计开展了边坡爆破开挖相似模型试验,分析了不同毫秒延时对爆破地震反应谱特性的影响,考虑结构密集振型间相互影响,结合完全二次项组合法(CQC)求得结构反应总效应值。结果表明:短毫秒延时控制爆破地震反应谱曲线体现为多峰值特性,且峰值对应周期范围窄,通常在几毫秒区间内;随孔间毫秒微差的增加,反应谱峰值对应结构自振频率逐渐降低,愈趋接近构筑物自振频率,不利于构筑物安全;合理孔间延期时间选取时,应综合考虑爆破振动强度、岩体爆破效果和构筑物动力效应特性3个方面因素;试验条件下,合理孔间延期时间为2 ms。The response spectrum theory widely applied in earthquake engineering was employed to investigate blasting seismic wave induced by controlled blasting with precise delay time interval. The similar model test of slope excavation was designed and carried out. The influence of different millisecond delay to response spectrum property was analyzed. Considering the interaction between intensive modes,the modal combination was conducted combined with method of second item combination completely（ CQC） to obtain total effect value of structural response. The results shows that,the response spectrum curves of controlled blasting with short millisecond delay have multiple distinct peak points,and the corresponding period is usually within a narrow range of a few milliseconds. With the increase of milliseconds delay between blasting holes,the natural frequency corresponding to response spectrum peak gradually close to the natural frequency of structures,which is detrimental to the safety of the structure. Choosing of reasonable delay time interval should comprehensively consider blasting vibration intensity,blasting effect of rock mass and dynamic response of construction. Under experimental conditions,the reasonable delay time interval between blasting holes is 2 ms.

关 键 词：边坡 爆破振动 反应谱 模态组合 CQC法 延期时间 

分 类 号：O382[理学—流体力学] TD235[理学—力学]