花岗岩超低温冻融循环后力学特性研究  

Mechanical Properties of Granite Under Ultra-low Temperature Freeze-Thaw Cycles

作　　者：张牡丹 王苏然 曾健霜 徐超[1] 王玥晗 ZHANG Mudan;WANG Suran;ZENG Jianshuang;XU Chao;WANG Yuehan(School of Environment and Architecture,University of Shanghai for Science and Technology,Shanghai 200093,China)

机构地区：[1]上海理工大学环境与建筑学院,上海200093

出　　处：《上海理工大学学报》2017年第5期484-489,共6页Journal of University of Shanghai For Science and Technology

摘　　要：对花岗岩进行-20,-30,-40,-50℃条件下的冻融循环处理,再进行单轴压缩试验,观察花岗岩经历不同冻结温度的冻融循环后的破坏模式,并分析弹性模量变化规律、应力应变曲线变化规律、单轴抗压强度和峰值应变变化规律以及冻融系数的变化.根据冻融处理后花岗岩的损伤数据,推广了花岗岩冻融循环后的总损伤变量的公式.研究结果表明,冻融循环后花岗岩的破坏模式主要为锥形破坏模式和柱状劈裂模式,揭示了花岗岩冻融循环后的力学特性与冻结温度的关系.根据总损伤变量与应变的关系可以预测,随着冻结温度的下降,应变存在一个临界值,超过临界值时试块破坏.Freeze thaw cycles tests on granite under different freezing temperatures were conducted,and then uniaxial compression tests were followed.The damage modes,stress strain curves,uniaxial compressive strength,peak strain and freeze thaw coefficients after different temperatures freeze thaw cycles were analyzed.In addition,a total damage variable after freeze thaw cycles was promoted.The results show that two kinds of damage modes of granite are found,including the columnar fracturing mode and the tapered damage mode.The relationship between the mechanical properties and freezing temperature under freeze thaw cycles of granite was revealed.According to the relationship between the total damage variable and strain,it can be predicted that the strain has a limited value with the decrease of freezing temperature.Rock will break when the strain exceeds the limited value.

关 键 词：花岗岩 冻融循环 单轴压缩试验 总损伤变量 

分 类 号：TU521.2[建筑科学—建筑技术科学]