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爆破震动灾害主动控制方法研究 总被引:3,自引:0,他引:3
在微差爆破工程中,用干扰降震法实现爆破震动灾害主动控制的关键在于确定合理的微差延期时间。由于所使用的普通雷管存在延期误差,设计或选择的延期微差时间往往与实际的有较大出入,影响了微差爆破的效果和顺利实施。确定微差爆破中的实际微差延迟时间对优化微差爆破效果、降低爆破地震效应具有很大的现实意义。用基于小波分析的时能密度法以及信号时-频域转换技术,从实测微差爆破震动信号中分离出各分段震波,通过比较各分段震波在不同延期时间下的叠加效果,得到了微差爆破的较优微差延期时间,实现了爆破震动灾害主动控制。该方法对研究爆破震动效应及其灾害的控制,具有较高的理论和应用价值,为系统开展爆破震动危害控制和预测研究奠定了理论和技术基础。 相似文献
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爆破震动信号的多分辨小波分析 总被引:3,自引:0,他引:3
采用小波分析和快速傅立叶变换相结合的方法,对工程案例的爆破震动近、中远区的实测原始信号进行小小波分解和重构,得到重构后各子频带的时间信号及频谱,在此基础上通过Matlab语言编写程序研究爆破地震波沿各分区信号的频谱及能量分布特征。指出:爆破震动各分区的主频从大到小排序为:近区>中区>远区;随着比例距离的增加,低频带能量所占信号总能量的比例升高,高频带能量所占比例下降;频率越低的频带信号,持续时间越长;除主频所在频带外,在0~2.441 5 Hz频段(比较接近建筑物的自振频率),爆破震动信号在水平方向占有不小的能量比例,故建筑物进行结构设计时考虑水平方向的抗震尤为重要。 相似文献
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凸形地貌对爆破震动波传播影响的数值模拟 总被引:2,自引:0,他引:2
应用UDEC程序模拟了爆破震动波在两种凸形地貌中的传播特征,并与广东岭澳核电站2期基础爆破开挖现场监测结果进行了对比。结果表明,凸形地貌对爆破震动波具有明显的放大作用,其数值模拟结果与现场监测结果吻合得比较好。研究结果还揭示,在一定爆破能量下,爆破震动波速度放大系数并不随台阶型凸形地貌的增高而单调增加,而是先随凸形地貌高度的增加而增加,在凸形地貌高度达到某一临界值时放大系数达到最大值,当凸形地貌高度超过这一临界值时,放大系数随凸形地貌高度的增加而减小。另外,在孤立凸形地貌下爆破振动波速度放大系数还与凸形地貌的高宽比有关。 相似文献
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H. P. Rossmanith K. Uenishi 《Fragblast: International Journal for Blasting and Fragmentation》2000,4(3):208-237
Bench blasting has a long tradition and yet the mechanics of throw and muck-pile formation is not clearly understood. This educational paper addresses bench blasting and muck-pile formation in a very simplified manner: a two-block system with ensuing formation of a two-block muckpile is investigated. It will become apparent that the study of a two-block system is perfectly sufficient for a deeper understanding of the problem of the entire bench blast and muck-pile formation. Two approaches will be presented: the momentum or impact approach and the wave propagation approach. The movement of the individual blocks and the formation of a 'two-block muck-pile' will be studied for both approaches and the differences in the results will be discussed. The purpose is to clarify, during blasting and ensuing block movement, the influence of the wave propagation action as compared to a purely gas-pressure based momentum treatment of muckpile formation. The results show that a wave propagation approach may lead to considerably different results for jointed rock mass and for certain combinations of parameters. 相似文献
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起爆时差是超深孔一次成井爆破设计中的一个重要参数,合理设计起爆时差和起爆顺序,能够达到先起爆炮孔为后起爆炮孔创造良好自由面和补偿空间,实现筒状硐室分层、分段爆破的目的,并能降低围岩震动破坏。为合理选取起爆时差,基于超深孔微差爆破破岩机制,从理论上推导了一次成井预裂爆破延期时间,掏槽孔与相邻辅助孔、同分段辅助孔、相邻分段辅助孔的起爆时差等计算公式;同时提出了自下而上预裂爆破、先上下后中间光面爆破等6种一次成井起爆顺序。在华恒矿-650矸石仓,结合施工条件合理确定起爆时差等爆破参数,形成爆破设计方案。爆破过程中实现了分层、分段爆破,获得了良好的硐室成型,验证了形成的超深孔微差爆破技术是成功的,其结果对类似工程的实施具有一定的参考价值。 相似文献
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S. P. Singh 《Geotechnical and Geological Engineering》1996,14(1):41-50
Summary A variety of overbreak control techniques are used during excavation with the drill and blast system. Tracer blasting is used in Canadian underground mines to minimize blast damage and involves placing a low-strength detonating cord along the length of a blast hole prior to charging with ammonium nitrate-fuel oil (ANFO). The results of tracer blasting are not always consistent and its mechanism is only hazily comprehended. In the absence of a clearly defined mechanism, it is difficult to analyse the results of tracer blasting and to identify the factors responsible for the inconsistency of results.A series of bench blasts and pipe tests were carried out to investigate the mechanism of tracer blasting. The evidence indicated partial deflagration and desensitization of ANFO, thus reducing the total available explosive energy. The rock mass surrounding the traced blasthole experienced a low level of ground vibrations. As a result of the continuous side initiation of ANFO, energy partitioning was more in favour of gas energy. A mechanism of tracer blasting has been proposed and the factors responsible for the inconsistency of the results have been identified in this paper. 相似文献
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爆破地震破坏判据的探讨 总被引:8,自引:0,他引:8
对比了旧、新爆破安全规程并分析了其中的缺陷,对爆破破坏判据进行了讨论。根据其缺陷提出通过小波分析和傅立叶分析把地震波信号划分为几个频带,采用加权速度结合频率破坏判据,分频考虑地震波的频率影响。对工程应用有较大的实用价值。 相似文献
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传统的地热井井身结构不适用于利用二氧化碳爆破技术进行干热岩储层建造,因此本文基于二氧化碳爆破致裂技术建造干热岩储层的新型井身结构工艺进行了进一步探究。结合该工艺水平井段(炮孔)钻进过程实际工况,对钻井后水平井段(炮孔)附近干热岩储层的物理力学性质变化规律及储层温度分布特征进行了岩石力学实验和数值模拟研究。研究结果表明钻井液降温产生的热应力作用是储层岩石性质发生变化、出现热损伤区的主要原因;冷却过程中炮孔附近储层呈现出“快速降温区-平缓降温区-未降温区”的区域性温度分布特征;储层初始温度和冷却时长对快速降温区温度分布以及热损伤区范围影响较大。本研究可以为二氧化碳爆破致裂干热岩储层建造提供理论指导。 相似文献
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并设小净距隧道爆破振动响应分析及控爆措施研究 总被引:3,自引:0,他引:3
通过大量二维、三维数值模拟计算,分析了围岩、净距、埋深等条件对小净距隧道爆破振动特性的影响,研究了先行隧道不同支护体系、不同中岩墙加固措施及后行隧道不同施工方案等情况下,小净距隧道中后行隧道爆破开挖对先行隧道的影响。根据研究结果,提出了中岩墙加固宜采用注浆加固、先行隧道初期支护宜及时跟进并封闭、掏槽眼宜远离中岩墙以及开挖进尺不宜大于净距的1/3等小净距隧道爆破施工的控爆措施,以供小净距隧道爆破开挖设计、施工借鉴。 相似文献
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隧洞开挖重复爆炸荷载作用下围岩累积损伤特性 总被引:1,自引:0,他引:1
隧洞毫秒爆破开挖推进过程中,预留岩体在重复爆炸荷载作用下产生不可逆的损伤叠加。而现有的岩体爆破损伤数值模拟基本都是针对单孔装药和单段爆破,很少涉及实际工程中的重复爆炸。基于LS-DYNA程序的用户自定义材料接口,将统计损伤演化模型嵌入到弹塑性本构材料中,模拟圆形隧洞全断面毫秒爆破过程中重复爆炸荷载作用下的岩体累积损伤效应,并考虑地应力对岩体爆破损伤的影响。计算结果表明,围岩损伤范围和损伤程度随重复爆炸荷载次数而增加,在一个爆破进尺内,围岩损伤的临界峰值质点振动速度较单段爆破降低了12%;爆炸荷载作用下,围岩主要表现为拉损伤,围岩地应力对爆破张拉效应起到非常敏感的"抑制"作用,在210 MPa应力水平时,围岩爆破累积损伤范围随着应力增加而明显减小,围岩损伤的临界峰值质点振动速度增加24%10 MPa应力水平时,围岩爆破累积损伤范围随着应力增加而明显减小,围岩损伤的临界峰值质点振动速度增加24%57%。 相似文献
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The analysis of ground vibrations induced by bench blasting at Akyol quarry and practical blasting charts 总被引:3,自引:0,他引:3
Umit Ozer Ali Kahriman Mehmet Aksoy Deniz Adiguzel Abdulkadir Karadogan 《Environmental Geology》2008,54(4):737-743
Ground vibrations arising from excavation with blasting is one of the fundamental problems in the mining industry. Therefore,
the prediction of ground vibration components plays an important role in the minimization of environmental complaints. In
this study, 582 events were recorded during limestone production at a quarry (Akyol Quarry) during a period of time. The blasting
parameters of these shots were also carefully recorded. During the statistical analysis of the collected data, three predictor
equations proposed by the United States Bureau of Mines (USBM), Ambraseys–Hendron and Langefors–Kihlstrom were used to establish
a relationship between peak particle velocity and scaled distance described by these prediction equations. As a result of
this analysis, the most powerful relationship was determined and proposed to be used in this site. And also, this equation
was used in the derivation of the practical blasting charts specific to this site as a practical way of predicting the peak
particle velocity and maximum charge amount per delay for future blasting. 相似文献