在硫酸盐环境下冻融-干湿循环对混凝土的影响  

Study on Sulphate Environment under Freeze-Thaw and Dry-Wet Cycling of Concrete

作　　者：金海军 于继寿[2] 李立辉[1,2] 吴志娟[2] 周红志 

机构地区：[1]北京建工集团新型建材有限责任公司,北京101104 [2]哈尔滨工业大学交通科学与工程学院,黑龙江哈尔滨150001

出　　处：《中国包装科技博览（混凝土技术）》2012年第2期1-7,共7页China Science and Technology Review

摘　　要：采用单一冻融、单一干湿和冻融-干湿循环交替作用的方法，研究了混凝土在不同浓度的硫酸盐溶液中的耐久性能。试验采用100mm×100mm×400mm试件直立完全浸泡进行干湿循环。研究表明，硫酸盐冻融-干湿循环作用下，溶液浓度对冻融破坏的影响存在临界值c=4．7％。当c≤4．7％时，冻融-干湿破坏随着溶液浓度的提高相对动弹性模量损失增大，而质量损失减小；当C〉4．7％时，溶液浓度对冻融破坏或冻融-干湿复合破坏影响不大。冻融-干湿破坏力最强、冻融破坏次之，干湿破坏最为缓慢；且干湿循环使冻融循环破坏加剧。试验发现15％FA取代水泥，混凝土抗硫酸盐腐蚀最佳。Single freeze-thaw cycles, single wet-dry cycles, and freeze-thaw and wet-dry cycles studied by means of concrete in sulfate solutions of different concentrations of durability. Experiment with 100mm x 100mm x 400mm upright specimen completely immersed for wet and dry cycle. Studies have shown that sulfate freeze-thaw and wet-dry cycles, the concentration on the impact of freeze-thaw cycles damage there is critical value C-- 4.7%, when C~〈4.7%, the freeze-thaw and wet-dry cycles destruction increased as the relative concentration the greater the loss of dynamic elastic modulus, while the smaller mass loss, when C〉 4.7%, the concentration of the freeze-thaw or freeze-thaw and wet-dry cycles damage has little effect; the freeze-thaw and wet-dry cycles destroy〉freeze-thaw cycles damage〉destruction of wet-dry cycles, wet and dry cycles to promote increased freeze-thaw damage; study found 15% FA replacement of cement, concrete resistance to sulfate corrosion of the best.

关 键 词：冻融-干湿循环 硫酸钠 相对动弹性模量 质量损失 

分 类 号：TU443[建筑科学—岩土工程]