摘要
用先高围压固结再卸载的三轴剪切蠕变试验方法模拟深部矿井软岩巷道开挖过程中应力状态随时间的变化过程,通过大量的试验获得:在试验围压范围内软岩蠕变强度包络线可以用Mogi-Coulomb准则来描述;侧向卸荷条件下软岩具有十分明显的剪胀性,且体积应变占总应变的10%～20%。为了全面反映极软岩在卸载状态下的蠕变变形规律,提出了考虑体积变形的Mogi-Coulomb屈服面型流变本构力学模型。对淮南某深部矿井软岩三轴蠕变试验和巷道开挖支护过程进行了有限元数值模拟,结果表明:提出的蠕变本构模型能够较好地反映软岩的剪胀性和体积应变等蠕变变形规律,数值模拟结果和现场实测吻合良好。
The triaxial creep test,after the first confining pressure consolidation and then unloading,simulated the stress state changes in deep soft-rock roadway in the excavation process,through the tests obtained：creep failure envelope can be described by the Mogi-Coulomb criterion within the experimental confining pressure;the soft rock has a very clear dilatancy on the condition of lateral unloading,and the volumetric strain occupies 10%～20% of the total strain.In order to fully reflect the extremely soft rock creep deformation law in the unloading state,proposed the Mogi-Coulomb yield surface rheological constitutive mechanical model,which considered the volume creep.The numerical simulation were carried out to the deep soft rock triaxial creep tests and the excavation process of roadway of one coal mine in Huainan.The results show that the creep constitutive model proposed can prefectly reflect the soft rock dilatancy and volumetric strain and other creep deformation laws.Numerical simulation results and measured values are in good agreement.
出处
《煤炭学报》
EI
CAS
CSCD
北大核心
2010年第10期1604-1608,共5页
Journal of China Coal Society
基金
国家自然科学基金资助项目(50804002
40972188)
高等学校博士学科点专项科研基金资助项目(200803610004)
