岩石中爆炸成坑效应的模型试验方法及对比分析

MODELING EXPERIMENT METHODS FOR CRATERING EFFECTS OF EXPLOSIONS IN ROCKS AND COMPARATIVE ANALYSIS

基于相似理论,推得爆炸成坑相似规律,建立爆破漏斗坑因变量与自变量之间的量纲一化的方程。阐述离心机试验系统和真空室试验系统模拟岩石中爆炸成坑的试验原理,通过参数敏感性分析,揭示2种试验系统各自的特点。离心机模型试验系统中吊篮尺寸与比例埋深、模型装药量成正比;离心加速度与原型装药量、模型装药量成正比;对模型材料、外部气压环境、爆源无特殊要求;因而离心机模型试验系统模拟小当量、浅埋深的爆炸试验具有明显的优势,不能用于模拟大规模的爆炸试验。真空室模型试验方法具有可控性强、无需提供额外加速度和适用范围广的特点,模拟大规模爆炸成坑现象时具有明显的优势;但其物理模型不包括岩石在爆炸作用下的动力破碎过程,不能模拟爆炸空腔形成过程和地冲击效应。

The similitude law and the dimensionless equations of cratering explosions were derived. Some basic principles essential to the centrifugal modeling system and the vacuum chamber modeling system were described according to the similitude law of cratering explosions. Some characteristics of the two kind modeling systems were revealed through the parametrical sensitivity analyses. The sizes of centrifugal modeling box are proportional to both the scaled depth-of-burial（SDOB） and the scaled explosive weight,and the centrifugal acceleration is proportional to both the prototype explosive weight and scaled explosive weight. There are no special requirements about the modeling materials,the external pressures and the explosion source. Generally,the centrifugal modeling system has clear advantages in simulating the small-scale and shallow-depth explosions;while it can not simulate the large-scale explosions. Actually,the vacuum chamber modeling system is more controllable and variable as there is no need to provide additional acceleration. Therefore,the vacuum chamber modeling system has superiorities in simulating the large-scale cratering explosions;but it does not consider the physical process of rock crushing and can not simulate the cavity formations and the impact effects.