摘要
采用动力有限元分析软件并结合混凝土损伤模型,对上部空气层间隔装药爆破作用下岩石动态应力场特性进行了分析研究。计算结果表明:受自由面以及炮孔内加、卸载波两方面的影响,临空面单元随着位置的增加,破坏方式由压剪破坏逐渐转变为剪切拉伸破坏。比较反向起爆与正向起爆动态应力场发现,反向起爆时爆轰气体对岩石的静态作用强度高、时间长,有利于克服孔底岩石所受的夹制力而不易产生根底。正向起爆时,大量爆轰气体自上部裂纹及孔口逸散,不利于爆炸能量的有效利用。
Based on the JHC （Johnson-Holmquist constitutive ceramic） model of concrete damage evolution,the dynamic stress characteristics of blast hole near-field on up air-decked charge structure was studied by numerical simulation. The results show that the failure mechanism of typical elements changes from compression-shear failure into shear-tensile failure gradually with the increase of their position,for the effecting factors of the free face and the loading from the hole. Comparing the dynamic stress characteristics of different initiation manners, indirect initiation can improve the static function intensity and duration of detonation gas, so it is easier to destroy the bottom rock of hole. But direct initiation releases the detonation gas from the rock crack and the hole-mouth early, so it is unfavorable to effective use of the exploding energy.
出处
《爆破》
CSCD
北大核心
2009年第4期17-21,共5页
Blasting
基金
国家自然科学基金(50774056)
湖北省自然科学基金(B20091103)
武汉科技大学校科学基金资助项目(080068)
