摘要
为研究冻融循环与硫酸盐侵蚀双因素耦合作用下混凝土的耐久性及其演变规律,分别通过混凝土单因素冻融循环试验、单因素硫酸盐侵蚀试验、硫酸盐侵蚀与冻融循环双因素耦合试验,分析各种因素下混凝土耐久性的劣化机理。试验结果表明:在单因素冻融循环、单因素硫酸盐侵蚀及硫酸盐侵蚀与冻融循环双因素耦合作用下,混凝土的质量均表现为先增大后逐渐减小;而混凝土的相对动弹性模量在单因素冻融循环作用下随着冻融循环次数逐渐减小,在单因素硫酸盐侵蚀、硫酸盐侵蚀与冻融循环双因素耦合作用下表现为先增加后减小,且经过60次单因素硫酸盐侵蚀作用后,混凝土的质量损伤率达到最小值,相对动弹性模量达到最大值。与单因素下两种侵蚀的损伤相比,双因素耦合作用对混凝土的损伤大于单因素损伤的叠加效果。
In order to analyze the durability and evolution of concrete under the combined action of freeze-thaw cycle and sulfate erosion,through the single freeze-thaw cycle test,the single sulphate dry and wet cycle test,the sulfate dry wet cycle and freeze-thaw cycle alternating test,the influence mechanism on durability of concrete was analyzed in this paper.The results show that:(1)under the action of single freeze-thaw cycle,single sulfate erosion,sulfate erosion and freeze-thaw cycle alternately,the mass of concrete increases first and then decreases;however,the relative dynamic elastic modulus of concrete decreases gradually in a single freeze-thaw cycle,increases first and then decreases under the action of single sulfate erosion,sulfate erosion and freeze-thaw cycle alternately.After 60 times of single sulfate,the mass reach the minimum value and relative dynamic elastic modulus of concrete reach the value maximum.(2)Compared to two kinds of erosion damage under single factor,the damage of concrete caused by two factors coupling effect is greater than the superposition effect of single factor damage.
作者
孙刚锋
缑彦强
SUN Gangfeng;GOU Yanqiang(Shaanxi Jinghui Canal Irrigation Administration,Xianyang,Shaanxi 713800,China;Sinohydro Engineering Bureau 4 Co.,Ltd.,Xining,Qinghai 810007,China)
出处
《水利与建筑工程学报》
2018年第6期140-144,共5页
Journal of Water Resources and Architectural Engineering
基金
国家自然科学基金项目(50779051)
关键词
冻融循环
硫酸盐侵蚀
混凝土
耐久性
freeze-thaw cycle
sulfate attack
concrete
durability
