摘要
通过混凝土经历两种超低温冻融循环作用工况的试验,探究混凝土超低温冻融循环作用下的受压变形性能。结果表明,随冻融循环作用次数的增加,超低温冻融循环作用上限温度时,因冻融损伤的累积效应使混凝土的弹性模量和峰值应变分别呈下降和增大的变化趋势;而超低温冻融循环作用下限温度时,因混凝土孔隙水结冰作用明显、产生的影响对冲了冻融损伤的累积效应使混凝土的弹性模量保持不变或略有增长、峰值应变变小。超低温冻融循环作用导致的混凝土弹性模量损失与其降温引起的峰值应变增长量有良好的对应关系,而超低温冻融循环的上限温度是否回到常温对混凝土受压变形性能的影响则不大。这些可为可靠地设计LNG类储罐预应力混凝土结构提供依据。
Stress-strain relationships of concrete undergoing cryogenic freeze-thaw cycles were tested and discussed.The freeze-thaw cycles were conducted by two ranges of temperature,both with a lower limit temperature of- 120 ℃, condition one has an upper limit temperature of-30 ℃, and condition two has an upper limit temperature of 20 ℃ .At the upper limit temperature, Young＇s module tends to decrease while peak strain tends to increase as the thermal loading goes on, and at the lower limit temperature, Young＇s module tends to increase while peak strain tends to decrease.The loss of Young＇s module because of the thermal loading corresponds well with the increase of peak strain because of cooling, and the two conditions of cycles make no big difference on the stress-strain relationships of concrete.Those results would be helpful for a better design of LNG containment.
出处
《混凝土》
CAS
北大核心
2017年第12期1-5,共5页
Concrete
基金
国家自然科学基金(51478242)
关键词
混凝土
超低温
冻融循环作用
上下限温度
弹性模量
峰值应变
concrete
cryogenic
freeze-thaw cycles
upper and lower limit of temperature
Young＇s module
peak strain
