摘要
为探究不同含水率花岗岩受荷作用下的力学特性及破坏特征。针对不同含水率条件下花岗岩开展单轴压缩试验,基于应力—应变曲线,分析了力学弱化特征,从宏观角度探究花岗岩变形破坏模式,通过能量理论计算,得出能量演化规律。研究结果表明:花岗岩试样应变软化特征明显,且随着含水率增加,峰值应力逐渐减小,非线性增加趋势明显,且伴有局部起伏涨落的趋势;花岗岩试样的抗压强度、弹性模量、脆性指标均随含水率增加而减小,饱和试样与干燥试样相比下降了40.1%、33.8%、61.8%;破坏模式随含水率增加而改变,崩落破坏时剧烈程度逐渐降低,干燥花岗岩呈现脆性劈裂破坏,破坏面以近竖直裂纹为主,低含水率花岗岩的破坏模式为拉—剪复合破坏,花岗岩近竖直裂纹数量减少,倾斜裂纹增多,随含水率增大呈现拉—剪复合破坏减少而剪切破坏增多,饱和岩样以剪切破坏为主,破坏面主要为倾斜破裂面;花岗岩的含水率越大,吸收能量的能力减弱,储能速率降低,但能量耗散现象显著。研究结果可为富水地区硬岩地下工程岩石工程灾害防控提供参考。
In order to investigate the mechanical properties and damage characteristics of granite with different water content under loading,uniaxial compression test was carried out for granite under different water content conditions.Uniaxial compression test was carried out for granite under different water content conditions,based on the stress-strain curve,the weakening characteristics of mechanics were analyzed,the deformation and damage modes of granite were investigated from a macroscopic point of view,and the energy evolution law was derived through energy theory calculations.The results show that:the strain softening characteristics of granite specimens is obvious,and with the increase of water content,the peak stress gradually decreases,the nonlinear increase trend is obvious,and accompanied by local undulation trend;granite specimens of compressive strength,modulus of elasticity,brittleness indicators are small with the increase of water content,saturated specimens compared with dry specimens decreased by 40.1%,33.8%,61.8%;damage mode with the increase of water content,and the damage pattern is small,and the damage mode is small.The damage pattern changes with the increase of water content,the intensity of the collapse damage gradually decreases,dry granite presents brittle cleavage damage,the damage surface is dominated by nearly vertical cracks,the damage pattern of low water content granite is pull-shear composite damage,the number of nearly vertical cracks in granite decreases,the number of tilted cracks increases,with the increase of water content presents a decrease in pull-shear composite damage and an increase in shear damage,saturated samples are dominated by shear damage,the damage surface is mainly tilted fracture surface.The saturated rock samples are mainly damaged by shear damage,and the damage surface is mainly inclined rupture surface;the larger the water content of granite,the weaker the ability to absorb energy,the lower the energy storage rate,but the energy dissipation phenomenon is significant.The results of the study can provide reference for the prevention and control of rock engineering disasters in hard rock underground projects in water-rich areas.
作者
庞建勇
王宇
巩义鑫
李垂宇
PANG Jianyong;WANG Yu;GONG Yixin;LI Chuiyu(School of Civil Engineering and Architecture,Anhui University of Technology,Huainan 232001,China)
出处
《金属矿山》
北大核心
2025年第1期81-88,共8页
Metal Mine
基金
国家自然科学基金项目(编号:52308129)。
关键词
花岗岩
单轴压缩
含水率
破坏特征
能量演化
granite
uniaxial compression
moisture content
failure characteristic
energy evolution
作者简介
庞建勇(1964-),男,教授,博士,博士研究生导师。
