裂隙水冻胀力和围岩温度应力对裂隙起裂影响分析  

Analysis of the Influence of Frost Heave Force of Crack Water and Temperature Stress of Surrounding Rock on Crack Initiation

作　　者：吴刚 陈伟 WU Gang;CHEN Wei(Jinan Huaiyin District Engineering Quality and Safety Center,Jinan 250021,China;School of Civil Engineering and Architecture,NingboTech University,Ningbo 315100,China)

机构地区：[1]济南市槐荫区工程质量与安全中心,山东济南250021 [2]浙大宁波理工学院土木建筑工程学院,浙江宁波315100

出　　处：《水电能源科学》2025年第4期110-114,共5页Water Resources and Power

基　　金：浙江省自然科学基金重点项目(LY20E080002)。

摘　　要：当寒区岩体冻结时,裂隙中的水冻结会导致体积膨胀,从而引起裂隙起裂。为得到裂隙水冻胀力和围岩温度应力共同作用下裂隙起裂的规律,基于质量守恒、弹性力学及水冰相变理论,建立了裂隙水冻胀力的解析方程。同时,结合弹性断裂力学理论,提出了裂隙水冻胀力和围岩温度应力共同作用下岩石裂隙起裂模型,并给出了应力强度因子的计算公式。在考虑裂纹尖端应力场常数项的影响的基础上,修正了现有的起裂准则,推导出最大起裂切向应力和临界起裂角的表达式,分析了裂隙尖端起裂应力及起裂角的变化规律,并通过数值模拟验证了理论结果。结果表明,当裂隙倾角较低时,裂隙起裂主要受控于裂隙水冻胀力;随着裂隙倾角的增大,围岩的温度应力对裂隙起裂的影响逐渐增大,起裂形式也从张拉转变为剪切起裂;裂隙起裂的最大切应力随冻结温度呈递增趋势,冻结温度为-20℃时,起裂切应力达到最大值;不同冻结温度下裂隙起裂角度的峰值约为74.1°。研究成果加深了对裂隙岩体冻胀破坏机制的认识,可供参考。When the rock mass is frozen in cold area,the freezing of water in the fracture will lead to volume sion,expan-which will cause the fracture to crack.In order to obtain the law of crack initiation under the combined action of frost heave force of fissure water and temperature stress of surrounding rock,analytical equations for frost heave pressure in the cracks were established based on the principles of mass conservation,elasticity,and the theory of water-ice phase transition.Simultaneously,a model for rock crack initiation under the combined action of frost heave pressure in the cracks and temperature stress in the surrounding rock masses was proposed based on the theory of elastic fracture chanics.me-The formula for calculating the stress intensity factor was given.Considering the influence of the stress field constant term at the crack tip,the existing initiation crack criteria were modified.The expressions for the maximum gential tan-stress for crack initiation and the critical crack initiation angle were derived.The variation laws of crack initiation stress and initiation angle at the crack tip were analyzed,and the theoretical results were verified through numerical lation.simu-The results show that when the crack angle is low,crack initiation is primarily controlled by frost heave pressure in the crack.With increase of the crack angle,the influence of temperature stress in the surrounding rock masses on crack initiation gradually intensifies,and the mode of crack initiation changes from tension to shear.The maximum shear stress for crack initiation increases with the freezing temperature,reaching its peak value at-20℃.The peak value of the crack initiation angle at different freezing temperatures is approximately 74.1°.This study deepens the understanding of the failure mechanism of fractured rock masses due to frost heave and provides valuable references for related research.

关 键 词：裂隙水 冻胀力 尖端应力 裂隙起裂角 改进的MTSED准则 

分 类 号：TU43[建筑科学—岩土工程]