湖山铀矿钙结砾岩的爆破损伤断裂过程与机理

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中图分类号：O383；TD868 国标学科代码：13035 文献标志码：A

Abstract：To study thedamage lawofcalcareous conglomerate under blasting，firstly，thedamage fracture procesand mechanism ofcalcareous conglomerate under blasting load were revealed basedonthe theoryof damagefracture mechanics.A meso-scalemodelofconglomerate，includingfiler，conglomerateandinterfacial transitionzone（ITZ），wasestablishedby using LS-DYNA and Fortran programming，and the propagation law of explosive stresswave and itsdamage characteristics were analyzed.The damage fracture process of calcareous conglomerate under blastingcan be divided into four stages， namely：compressiondamage inboth graveland fil;tensileamage ingravelandcompresion damageinfil;tensiledamage inbothgravelandfill;andtensile damageattheintersectionof gravelandfill.Numericalresultsshowthatunderblasting loads，thegravelashigherequvalentstresses，thefillhasthelowest，stressconcentrationisevidentatteIZ，andtestrss gap between the gravel and the filldecreases asthedistance increases.The conglomerate sustains relatively minordamage， withanotablephenomenonof damageoccuring aroundit.However，thefller experiences significantdamage.The expansion ofblasting crack incalcareous conglomerate formsmainlyalong the direction of stress wave propagation. Cracks tend to developalong the filer with lower physical and mechanical properties，as wellas along the junction surfaces.The damageto thegravel iscomparativelylessevere.Blasting blockiness ismainlymanifestedasthe filer wrappinggravel，andthe distributionofblasting blockinessisaectedbythebonding forceat theintersectionsurfaceandthedistributionof gravel.

Keywords： calciumconglomerate; damage and fracture mechanism; meso-scale modeling models; destruction characteristics

湖山铀矿位于非洲纳米比亚中西部的纳米布沙漠，是全球第三大铀资源矿产，资源量总计31.1万吨，是我国天然铀供应保障的“压舱石”。（剩余15979字）