不同傾角充填節(jié)理對巖石爆破塊度的影響

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中圖分類號：0346;0389 國標學科代碼：13015；13035 文獻標志碼：A

Influence of filled joints with different inclination angles on rock blasting fragmentation

TAO Ming1， CAO Zheng1， ZHAO Rui1， LIU Yulong，LI Xibing1 （1.SchoolofResourcesandSafetyEngineering，Central South UniversityChangsha41o83，Hunan，China; 2. CGNPC Uranium Resources Co.，Ltd.， Beijing 100029， China）

Abstract： To understand the interaction between joints and blasting stresses and optimizing blasting parameters in jointed rock，theimpactof diferent joint inclinationson blasting fragmentation was studied throughacombinationof testsand numerical simulations.Inthisstudy，agroupofconcretemodelspecimens containing joints withdiferentangleswas used in the blasting teststoinvestigatetheeectofjoint inclinationonblastfragmentation.Duringtests，detonators wereplacedin verticalboreolesinthespecimensanddetonated，whilehghspeedcamerawasusedtocapture thefragmentationproess.The dynamicresponsesof jointsurfacesatdiferenttimeintervalsafterdetonationwasobserved，andblastingfragmentation distributin was extracted using image processng techniques.The efect of joint inclination on blasting fragmentatio was analyzed.The propagation ofstress waves andthe evolution ofstraifields within thespecimens was obtainedifinite element numerical simulations byusingLS-DYNA.Experimentaland numerical results indicated that the joints have a significant influenceonthe distribution of blasting fragmentation and the propagation of stress waves.The impact of the joints on the blasting performance was mainlyatributed tothereflection of blasting waves from the joints，which was related to the deformationcharacteristicsofthejoints.Withtheicreaseofjointinclination，theblastingfragmentationinitialldecreased followed byanincrease.Theeffective stressand peak particlevelocitytransmissioninthejoints decreased overall with the increase of joint inclination， but showed a rebound between 45° and 60° .This suggests approximately 45° is the most favorable condition forrock fragmentation under blasting.Moreover，the resultsobtainedfrom numerical crack network reconstruction and image processng revealed that there was anupsurge in the occurrence of verticalcracks in the specimen as the joint inclination increased， while a decline was observed in the presence of horizontal cracks.

Keywords：blasting model tests; jointed rock mass; stress Wave; fragmentation distribution of blasting

天然巖石中含有大量的微觀和宏觀不連續(xù)面。（剩余22660字）