硫酸镁溶液对应力作用下混凝土抗冻性的影响  

Effect of magnesium sulfate solution on frost resistance of concrete under stress condition

作　　者：张云清[1] 余红发[1] 孙伟[2] 刘俊龙[1,3] 张建业 

机构地区：[1]南京航空航天大学航空宇航学院,江苏南京210016 [2]东南大学材料科学与工程学院,江苏南京211189 [3]浙江建设职业技术学院建筑工程系,浙江杭州311231 [4]中国土木工程集团有限公司,北京100038

出　　处：《交通运输工程学报》2010年第6期15-19,共5页Journal of Traffic and Transportation Engineering

基　　金：国家973计划项目(2009CB623203);中央高校基本科研业务费专项资金项目(NS2010015);江苏省自然科学基金项目(BK2005216);南京航空航天大学博士学位论文创新与创优基金项目(BCXJ07-04)

摘　　要：制备了掺加20%粉煤灰的高强混凝土(HSC)、复合掺加40%粉煤灰、10%矿渣和5%硅灰的大掺量矿物掺合料混凝土(HVMAC)和综合运用引气剂、高效减水剂、大掺量矿物掺合料、混杂纤维和膨胀剂技术的高耐久性混凝土(HDC),采用快冻法测定了混凝土在水和5%MgSO4(质量分数)溶液中的抗冻性。在冻融过程中对试件采用三分点加载方式,设定弯拉应力为破坏应力的35%。分析结果表明:与水中冻融条件相比,MgSO4溶液分别使HSC和HDC在应力作用下的抗冻性提高了46倍和70%以上,其抗冻融循环次数分别达到了425次以上和900次以上,但却使HVMAC在应力作用下的抗冻性降低了67%,抗冻融循环次数仅为75次。The frost resistances of three kinds of concretes under flexural stress subjected to water and 5% MgSO4（mass fraction） solution were studied by using accelerated freezing-thawing method.The considered concretes include high strength concrete（HSC） added with 20% fly ash（20% of binder mass）,high-volume mineral admixture concrete（HVMAC） added with 40% fly ash,10% slag and 5% silica fume,and high durable concrete（HDC） added with high-volume mineral admixture,air-entraining agent,superplasticizer,fibres and expansion agent.Third point loading method was applied on the specimens in the process of freezing-thawing cycle,and the enacted flexural stress was 35% of failure stress.Analysis result shows that the frost resistances of HSC and HDC respectively increase 46 times and more than 70% under flexural stress subjected to MgSO4 solution as compared with water,and their anti-freezing-thawing cycles are respectively more than 425 times and 900 times.But the frost resistance of HVMAC decreases by 67% under flexural stress,and its anti-freezing-thawing cycles are only 75 times.3 tabs,4 figs,15 refs.

关 键 词：混凝土 弯拉应力 硫酸镁腐蚀 抗冻性 相对动弹性模量 

分 类 号：TU528[建筑科学—建筑技术科学]