冻融循环作用下盐分对混凝土耐久性影响的试验研究  

Experimental Research of Salinity on Durabiltiy Influence of Concrete under Freeze-thaw Cycle

作　　者：田俊壮 夏慧芸[1] 牛昌昌 张雷[1] 陈华鑫[1] 

机构地区：[1]长安大学材料科学与工程学院,西安710061

出　　处：《混凝土与水泥制品》2016年第3期1-6,共6页China Concrete and Cement Products

基　　金：国家自然科学基金项目(51202016)

摘　　要：以青海德香高速公路大桥桥墩混凝土为依托,对其沿线主要易溶盐含量进行分析,通过室内模拟实验,配制了7种腐蚀溶液,并设计四种配合比混凝土,通过外观形貌、质量损失率和相对动弹模量三方面研究冻融循环作用下,盐分对混凝土耐久性的影响。结果表明:盐蚀-冻融循环作用下,单一盐类如Na2SO4、Mg SO4、Na Cl溶液对混凝土破坏形式和程度均不相同;上述几种盐的复合溶液对混凝土的破坏同时存在促进和抑制作用,即在低浓度盐溶液中,盐分加剧混凝土的冻融损伤,在高浓度盐溶液中,溶液冰点很低,缓解了混凝土冻融损伤。Based on bridge pier concrete of Dexiang highway bridge in Qinghai Province, the concentration and the main types of the dissolved salts along Dexiang highway were analyzed, and seven solutions of different concentration of salt were prepared and four kinds of concrete were designed by laboratory experiments. Surface morphologies, weight loss rate and relative dynamic elasticity modulus were used to study the effects of salt on concrete durability under freeze-thaw cycle. The results show that under salt corrosion-freeze-thaw cycle tests, the corrosion damage forms and extents of concrete are different when different single salt solution was adopted,such as Na2SO4, Mg SO4 and Na Cl. However, promotion and inhibition exist at the same time, when salt freeze damage was conducted in composite salt solution. Low concentration salt aggravates freeze-thaw damage of concrete, when the concentration of salt solution is high, freezing point is very low,which can reduce freeze-thaw damage of concrete.

关 键 词：道路工程 冻融循环 耐久性 冻融损伤 抗盐冻性 

分 类 号：TU528.01[建筑科学—建筑技术科学]