基于岩体爆破累积损伤效应的Hoek-Brown准则修正公式

爆破开挖作业引起的扰动与损伤,特别是频繁爆破产生的累积损伤效应,必然导致岩体完整性降低,岩体力学参数弱化,从而威胁岩体工程稳定性。考虑岩体爆破损伤及其累积效应,指出了Hoek-Brown(赫克-布朗)准则及其改进公式的不足,引入完整性系数K v和损伤因子D,建立了可以表征岩体爆破累积损伤效应、岩体爆破扰动状态及其力学参数弱化程度的mb和s的取值方法。基于声速变化与爆破累积损伤效应之间的联系,建立了以岩体声速降低率η为基准量的岩体爆破累积损伤扩展模型,并将该模型成功应用于提出的Hoek-Brown准则修正公式中。根据现场模拟爆破试验与声波测试数据,对提出的修正公式进行了分析,结果表明,建立的考虑岩体爆破累积损伤效应的Hoek-Brown准则修正公式是合理的。

Amended expressions of Hoek-Brown criterion based on blasting cumulative damage effects of rock mass

The disturbance and damage induced by excavation and blasting,especial blasting cumulative damage effects resulted from frequent blasting,will play down the integrity of rock mass,weaken the mechanical parameters of rock mass and threaten the stability of rock engineering surely.Considered the blasting cumulative damage effects of rock mass,the shortages of Hoek-Brown criterion and its modified expressions were pointed out.The methods of obtaining the value of and s which could reflect the blasting cumulati...