摘要
选取2008年极端冰雪受灾地区灰色砂岩,制作岩石与C20喷射混凝土组合试样,通过冻融循环试验、单轴压缩试验、中/低不同围压三轴压缩试验、中/低不同轴压直剪试验及微观扫描试验系统研究岩石-喷射混凝土组合试样的宏观物理力学性质及微观破坏机制。试验结果揭示研究对象在不同含水状态(干燥或饱和)、不同冻融循环次数条件下的损伤模式、破坏准则及强度指标变化规律。在此基础上,建立冻融前后组合试样的损伤软化统计本构模型。经与三轴压缩试验曲线对比,该本构模型能较真实地反映破坏的全过程,可靠性较高。
The gray sandstone from disaster area of extreme ice and snow in early 2008 is selected to make the combined specimen with gray sandstone and C20 shotcrete.Through different kinds of tests,i.e.freezing-thawing cycling test,uniaxial compression test,triaxial compression test under medium and low confining pressures,direct shear test under medium and low axial pressures,micro-scanning test,the macroscopic physico-mechanical properties of combined specimen with rock and shotcrete and its micro-damage mechanism are both studied systematically.The test results reveal the damage mode,failure criterion and variation of strength indices of the combined specimen with different water contents(dried or saturated) after different freezing-thawing cycles.Based on the above results,the damage softening statistical constitutive models for combined specimen with rock and shotcrete before and after freezing-thawing are established.By contrast with the curves of triaxial compression test,the new damage softening statistical constitutive models can truly reflect the entire damage process and the models are considered to be reliable.
出处
《岩石力学与工程学报》
EI
CAS
CSCD
北大核心
2010年第12期2510-2521,共12页
Chinese Journal of Rock Mechanics and Engineering
基金
"十一五"国家科技支撑计划项目(2008BAC47B0X)
关键词
岩石力学
极端冰雪灾害
冻融
组合试样
破坏准则
本构模型
rock mechanics
extreme ice and snow disaster
freezing-thawing
combined specimen
failure criterion
constitutive model