岩巷爆破围岩损伤演化方程及稳定性分析

本文以岩体微观缺陷的分布和Weibull理论为基础 ,定义了一个损伤变量。通过该损伤变量推倒的损伤演化方程 ,不仅表征了岩体的不可逆动态损伤演化过程 ,而且和微观缺陷的起裂、扩展和传播以及岩体性能的劣化建立了联系。并且 ,根据损伤理论对岩巷爆破围岩的稳定性进行了分析     

岩石破碎机理的微差爆破最佳延时控制

为探究微差爆破最佳的孔间起爆延期时间,从岩石破碎机理出发,将应力波和爆生气体能量综合作用方式作为研究载体,结合波动学理论、热力学理论以及断裂力学理论,推导出应力波和爆生气体作用下的运动和动力学方程、破坏范围、作用时间和传播速度的数学公式.在此基础上,运用推导出的物理参数对哈努卡耶夫提出的延时控制半经验公式进行修正,得出了微差爆破延期时间选取的理论模型.最后,结合某露天矿进行不同段别高精度澳瑞凯雷管组合的微差爆破实验,结果显示此次试验爆破后效果最佳延期时间为25 ms,而将该地质条件的力学参数代入推导得出的最佳延期理论模型,得出延期时间为24 ms左右,说明该理论模型与本次实验结果较为吻合.     

双孔切槽爆破裂纹扩展的动焦散实验

应用爆炸加载动态焦散线测试系统,研究了不同切槽方式下,双孔同时起爆时贯穿裂纹的扩展行为及裂纹尖端应力强度因子的变化情况.实验结果表明：炮孔间两切槽方向优先扩展的主裂纹,裂纹尖端并未直接相遇,而是发生偏转并移向异方已经形成的裂纹.裂纹扩展速度先减小,振荡变化后逐渐升高到峰值,随后减小,振荡变化后直至裂纹止裂.应力强度因子KI由初始时的最大值迅速减小,反复振荡后,又逐渐增大至第2个峰值,之后开始减小.定性的分析了应力波与裂纹尖端相互作用机理.     

岩体爆裂成缝的计算机模拟分析

分析了岩体爆裂成缝的计算机模拟的可行性和影响因素，编制了计算机模拟程序，计算机模拟表明，爆裂成缝是爆炸应力波和爆生气体联合作用的结果。     

Model experiment of rock blasting with single borehole and double free-surface

In order to improve the quality of laneways and tunnel excavation by drilling and blasting and by making effective use of explosive energy, a model experiment of rock blasting with a single borehole and a double free-surface was performed with the objective of studying the effect of parameters such as charge structure, free-surface and rock compressive strength on rock blasting. The model experiments indicate that: 1) the smaller the rock compressive strength and density, the more distinctive the cavity expanding action by blasting; 2) the powder factor in an air-decoupling charge structure is larger than that in a coupling charge structure, i.e., the explosive energy in an air-decoupling charge structure transferred to the rocks is less than that in a coupling charge structure; 3) a free-surface improves the utilizations of explosive energy; 4) an air-decoupling charge structure helps to maintain the integrity and stability of wall rock in controlled perimeter blasting, such as in roadways and tunnel excavation by drilling and blasting.     

露天矿山深孔台阶爆破振动监测与分析

针对露天采石场深孔台阶爆破振动可能对附近民房存在影响,进行了爆破振动监测．通过对采集的数据进行全面分析得出,该地形地质条件下,台阶爆破振动速度的衰减规律、不耦合系数与振动速度之间的关系．监测及分析结果对今后类似地形、地质条件下矿山深孔台阶爆破开采具有一定的参考意义．     

Measurement-while-drilling technique and its scope in design and prediction of rock blasting

With rampant growth and improvements in drilling technology,drilling of blast holes should no longer be viewed as an arduous sub-process in any mining or excavation process.Instead,it must be viewed as an important opportunity to quickly and accurately measure the geo-mechanical features of the rock mass on-site,much in advance of the downstream operations.It is well established that even the slightest variation in lithology,ground conditions,blast designs vis-à-vis geologic features and explosives performance,results in drastic changes in fragmentation results.Keeping in mind the importance of state-of-the-art measurement-while-drilling(MWD) technique,the current paper focuses on integrating this technique with the blasting operation in order to enhance the blasting designs and results.The paper presents a preliminary understanding of various blasting models,blastability and other related concepts,to review the state-of-the-art advancements and researches done in this area.In light of this,the paper highlights the future needs and implications on drill monitoring systems for improved information to enhance the blasting results.     

南水北调西线工程深埋隧洞岩爆与地应力研究

在分析深埋隧洞岩爆破坏机制和地应力条件的同时 ,详细论述了南水北调西线工程主要引水线路区的现代构造应力场特征及主应力的大小、相互关系 ;根据地应力、岩性等特征初步评价主要引水线路区隧洞围岩发生岩爆的可能性     

禹门口一级提水泵站岩坎围堰拆除控制爆破设计

禹门口一级提水泵站岩坎爆破拆除是难度极大的控制爆破工程 .由于岩坎爆破的周围环境复杂 ,拆除用药量过大及防护不当 ,势必对邻近建筑物产生破坏 .经设计人员研究分析 ,岩坎拆除分两部分进行 ,首先在岩坎内侧 (向建筑物一面 )采用层层剥皮的爆破方式 ,以减少最终预留岩坎一次爆破的难度 ,然后进行预留岩坎的水下拆除 ,确保预留岩坎一次爆破成功 .对剥皮部位拆除爆破作了较为详细的介绍     

大型冷却塔控制爆破技术及危害控制措施

在电厂正常发电的情况下,为保证近邻建筑安全使用和设备正常运行,以理论计算为基础,结合工程实际和试爆合理选取最佳爆破缺口参数,是控制冷却塔倒塌的关键.分区、分段微差爆破可降低倒塌空气冲击波的速度.预开减震窗破坏冷却塔的整体性,使冷却塔在倾倒过程中处于一种边倾倒、边着地、边破碎的软着陆状态,可有效地减小塔体倒塌产生的触地振动.在塔壁倒塌方向的背面预开泄气窗可降低倒塌空气冲击破坏程度.上述措施的成功应用为类似工程施工提供了借鉴.     

侧爆作用下锚固洞室破坏形式及机理研究

为了进一步提高锚固洞室在侧爆作用下的抗爆能力,利用数值分析软件LS-DYNA3D程序,研究了在侧爆作用下的锚固洞室的破坏形式及机理.数值分析结果表明:压应力波一开始是以球形向四周传播的,当压应力波碰到洞室壁时,会在洞室壁表面产生拉应力波,并以椭圆形式向反向传播;在应力波整个传播过程中,由于反射拉伸可能会在洞室锚固区和非锚固区先后产生二次拉伸破坏,最后可能会由于洞室反射的拉伸波和地面反射拉伸波相遇共同作用,在离地面比较浅的地方产生拉伸破坏区.     

Numerical analysis of tunnel reinforcing influences on failure process of surrounding rock under explosive stress waves

Based on mesoscopic damage mechanics, numerical code RFPA2D （dynamic edition） was developed to analyze the influence of tunnel reinforcing on failure process of surrounding rock under explosive stress waves. The results show that the propagation phenomenon of stress wave in the surrounding rock of tunnel and the failure process of surrounding rock under explosive stress waves are reproduced realistically by using numerical code RFPA2O; from the failure process of surrounding rock, the place at which surrounding rock fractures is transferred because of tunnel reinforcing, and the rockfall and collapse caused by failure of surrounding rock are restrained by tunnel reinforcing; furthermore, the absolute values of peak values of major principal stress, and the minimal principal stress and shear stress at center point of tunnel roof are reduced because of tunnel reinforcing, and the displacement at center point of runnel roof is reduced as well, consequently the stability of tunnel increases.     

Damage and fragmentation of rock under experiencing impact load

1 INTRODUCTIONThe dynamic fragmentation of brittle materialsexperiences an extremely complex process ,invol-ving micro-cracks nucleation,propagation and coa-lesce , which breaks the solid into fragments . Butthe process canfall into two successive phases gen-erally : damage stage and fragmentation phase .The most widely applied theoretical models of theprocess , such as those based on the pioneeringstudies of Grady[1], Glenn et al[2],involve sometype of relatively si mple global energy ba…     

空气间隔与耦合装药混凝土爆破对比分析

采用动力有限元软件LS-DYNA分析空气间隔装药与耦合装药结构对混凝土介质的破坏机理,结合混凝土模型对两种装药结构进行了光面爆破试验。结果表明,采用空气间隔装药结构进行爆破后,混凝土表面平整度要优于无空气间隔的情况;空气间隔装药结构能调节炸药能量分布,使孔内爆炸压力沿炮孔轴向的分布更均匀,从而提高炸药爆炸能量的有效利用率。     

Failure mechanism of Mesozoic soft rock roadway in Shajihai coal mine and its surrounding rock control

In view of the buckling failure caused by large deformation of Mesozoic soft rock roadway in Shajihai mining area, such as serious roof fall, rib spalling, floor heave, etc., based on the detail site i...     

槽挖爆破对倒悬体的振动影响监测与分析

详细介绍了三峡工程永久船闸左线二闸首中隔墩倒悬体下部岩石的控制爆破与振动监测 ,并对爆破的振动影响进行了分析 .     

太子矶航道水下钻孔爆破地震波测试与分析

以长江太子矶航道疏浚爆破工程为例,通过对其爆破地震波的测试与分析,得出爆破振动速度的衰减经验公式,提出爆破振动速度安全判据及不同状态下的最大允许药量,并依据实测数据评估了水下钻孔爆破对长江大堤的影响。     

水工隧洞检修期衬砌与围岩联合承载作用机理

衬砌与围岩是水工隧洞的主要组成部分,外水压力是其承担的主要荷载之一.结合某水电站工程实例,建立其发电引水隧洞的有限元数值分析模型,针对衬砌与围岩有条件联合承载作用特征,对衬砌外围岩变形模量进行折减以反映围岩的作用,并引入具有一定抗拉强度的薄层单元量化反映衬砌与围岩有条件联合承载能力.结果表明:与衬砌完全单独承载外水压力计算结果相比,围岩在承担外水压力中的作用不容忽视,且随着外围岩体变形模量的增加,其所分担的外水压力越大;采用薄层单元量化后,衬砌与围岩的联合承载机理更为明确,薄层单元开裂前,围岩承担外水压力较多,薄层单元开裂后,衬砌承担外水压力较多,因而要确保回填灌浆和固结灌浆质量,以提高衬砌与围岩联合承载能力.     

埋藏式钢岔管与围岩联合承载有限元分析

以某水电站工程为例,考虑钢衬与围岩间的缝隙值,按照钢衬与围岩联合承载,采用三维有限元方法对地下埋藏式钢岔管进行计算分析,讨论了围岩性能及初始缝隙值对围岩承载比的影响,并与明管计算结果相比较,指出在钢衬与围岩共同承受内水压力作用时,围岩发挥了重要作用.     

复杂条件下巷道围岩破坏机理及支护方案研究

从许厂煤矿复杂的地质构造入手,分析了复杂地质构造所引起的高应力特征,并结合围岩物理力学特性对巷道围岩变形破坏特点及破坏机理进行了分析,提出了复杂地质构造及高应力条件下软岩巷道的安全支护技术措施.该结果对同类型工程的设计与施工具有重要的参考价值.