高地应力下脆性岩体工程开挖变形机理、稳定性评价及灾害控制技术研究一直是岩石力学和工程地质研究的难点问题。基于高应力下脆性岩石卸荷力学试验分析,明确了卸荷过程中的岩石力学参数及变形破坏演化规律,发现高应力下脆性岩石的破坏具有较明显的应变强度特征。分析了高应力下脆性岩石卸荷破坏采用张拉屈服的Griffith应变强度准则的合理性,建立了考虑卸荷屈服引起岩体力学参数变化的弹脆塑性数值计算方法,并在实际工程中得以验证。
The investigations on the deformation mechanisms,estimation of stability and technique of disasters controlled of brittle rocks excavated under high geostress are difficult points for rock mechanics and engineering geology.The evolutionary rule of mechanical parameters and deformation failure of brittle rocks are discussed based on unloading under high geostress,and the obvious characteristics of strain strength for brittle rocks under high geostress is found.It is presented that the brittle rock yielded follows Griffith rule of strain strength at peak.The elasto-brittle-plastic numerical calculation method is established considering the dynamical variation of mechanical parameters in course of unloading yield,and it is validated by practical engineering.