工程中预裂爆破参数确定方法通常为经验类比法。该方法以经验公式为基础,存在理论依据较为缺乏等缺点。为此,引入岩石爆破损伤、应力波和爆生气体共同作用等理论,在考虑岩石初始损伤等影响因素的基础上,提出预裂爆破参数计算式。基于提出的理论方法,在现场开展了预裂爆破试验。针对爆破试验,比较了采用经验类公式和提出的理论计算式得到的线装药密度,并对爆破效果进行了分析。试验结果表明,预裂爆破效果良好。考虑爆破损伤效应的爆破参数确定方法比经验类比法合理。最后,在提出的理论计算方法基础上,给出了实际工程中确定预裂爆破参数的建议。
Generally, presplitting blasting parameters are obtained by the engineering analogy method, which is according to the empirical formulations. However, this method lacks theoretical basis. Therefore, it s necessary to propose new formulations on the presplitting blasting parameters in consideration of some important blasting influence factors such as rock initial damage. Two theories of rock blasting-induced damage and the interaction between stress wave and donation gas are introduced. For practical project, the presplitting blasting tests are conducted to obtain blasting parameters in field by the present method. The results of the linear charge density calculated both by some representative empirical formulations and the proposed theoretical formulations are compared, and then the effects of presplitting blasting tests are analyzed. Experimental results show that the effects of presplitting blasting tests perform well, and the presplitting blasting parameters by the developed method is more rational than that obtained with the engineering analogy one. Finally, some useful suggestions are given to determine presplitting blasting parameters in practical project based on the theoretical method.