极端温度下CRTS Ⅰ型板式无砟轨道CA砂浆受压伤损试验  

Compression Damage Experiment Of CRTS Ⅰ Type CA Mortar under Extreme Climate

作　　者：丁维桐 杨吉龙 吴梦瑶[1] 杨荣山[1] DING Wei-tong;YANG Ji-long;WU Meng-yao;YANG Rong-shan(MOE Key Laboratory of High-Speed Railway Engineering,Southwest Jiaotong university,Chengdu 610031,China)

机构地区：[1]西南交通大学高速铁路线路工程教育部重点实验室,成都610031

出　　处：《铁道标准设计》2018年第11期25-28,共4页Railway Standard Design

基　　金：国家自然科学基金重点资助项目(U1434208)

摘　　要：CA砂浆是一种温度敏感性材料,温度变化将直接影响其受压承载的性能。为了研究极端温度对CA砂浆性能产生的影响,将CRTSⅠ型CA砂浆分别放在-50、-40、-30、20、40、60、80℃环境下进行单轴压缩试验,分析CA砂浆在不同极端温度下受压的规律以及伤损特性。结果表明:随着温度的升高,CA砂浆的抗压强度和弹性模量变小,并利用模量-温度曲线更直观地表现出CA砂浆由脆性逐渐转变为塑性,同时给出了受温度影响的CA砂浆温度-抗压强度的经验公式。以切线模量的变化来判断CA砂浆的温度损伤程度,分析CA砂浆温度损伤规律和伤损槛值随温度的变化规律,随着温度的升高,CA砂浆损伤应力槛值减小,当温度增大到一定时,CA砂浆的应力槛值与抗压强度的比值RC受温度的影响不是很明显。CA mortar is a temperature-sensitive material and the temperature change directly affects theperformance of its load-bearing. In order to study the effect of extreme temperature on CA mortarperformance, compression tests are carried out at -50 ℃, -40 ℃, -30 ℃, 20 ℃, 40 ℃, 60 ℃ and80 ℃ respectively. The regularity and damage characteristics of CA mortar under different extremetemperatures are analyzed. The results show that CA mortar compressive strength and elastic modulusbecome smaller with the increase of temperature, and the modulus-temperature curve is more intuitive toshow that the CA mortar is changing from brittleness to plastic. Then, the empirical formula of temperaturecompressive strength of CA mortar affected by temperature is given. The degree of CA mortardamage is estimated based on the tang-ential modulus changes and the rule of temperature damage of CAmortar and that of damage threshold with the change of temperature are analyzed. With the increase oftemperature, the damage threshold of CA mortar decreases. When the temperature increases to a certainlevel, the ratio of the stress threshold to the compressive strength of the CA mortar RC is not significantlyaffected by the temperature.

关 键 词：板式无砟轨道 CA砂浆 极端温度 受压 伤损特性 抗压强度预测 应力槛值 

分 类 号：U213.244[交通运输工程—道路与铁道工程]