掺合料、早强剂对冻融混凝土Cl^-扩散系数的影响  

The Study on Chloride-Ion-Diffusion-Coefficient of Concrete Mixed Admixture,Early Strength Agent After Freeze-Thaw Cycling

作　　者：张巨松[1] 张微[1] 邓嫔[1] 韩自博[1] 吴晓丹[1] 朱林[1] 

机构地区：[1]沈阳建筑大学材料科学与工程学院,辽宁沈阳110168

出　　处：《沈阳建筑大学学报（自然科学版）》2009年第1期143-147,共5页Journal of Shenyang Jianzhu University：Natural Science

基　　金：建设部科技攻关项目(2007-k4-19);沈阳市地铁攻关项目

摘　　要：目的研究粉煤灰、矿粉、掺硫酸钠粉煤灰、掺硫酸钠矿粉混凝土冻融循环后Cl-扩散系数,解决混凝土冻融循环后的内部结构损伤问题.方法采用慢冻法冻融、NEL法测试冻融循环后混凝土Cl-扩散系数.结果掺入粉煤灰的质量分数低于30%时,掺入矿粉的质量分数低于40%时,经100次冻融循环后混凝土Cl-扩散系数均低于基准混凝土.经冻融循环后,掺硫酸钠矿物掺合料的混凝土在一定的矿物掺合料掺量范围内,混凝土Cl-扩散系数低于基准混凝土.经冻融循环后,掺硫酸钠矿物掺合料的混凝土Cl-扩散系数高于未掺硫酸钠的矿物掺合料混凝土.结论掺粉煤灰混凝土、掺矿粉混凝土的抗冻性好坏取决于矿物掺合料掺量范围.掺硫酸钠粉煤灰混凝土、掺硫酸钠矿粉混凝土,在一定矿物掺合料的掺量范围内,混凝土抗冻性好于基准混凝土.但是硫酸钠的加入使得混凝土抗冻性比未掺硫酸钠混凝土抗冻性差.The NEL method is applied to test the chloride - ion - diffusion - coefficient of concrete. Chlorine ion diffusion coefficient of fly - ash, slag, Na2 SO4 and after freeze - thaw cycling is studied. Then internal structure damage situation of concrete after freeze - thaw cycling is studied too. It is found that the concrete in which the quantity of fly - ash admixtures is lower than 30%, the quantity of slag admixtures is lower than 40% ,chloride ion diffusion coefficient is lower than the datum concrete after 100 freeze - thaw cycling. After the freeze - thaw cycling, in a certain scope of the mineral admixtures quantity the chloride ion diffusion coefficient which is added Na2 SO4 and mineral mixes is lower than datum concrete. After the freeze - thaw cycling, the chloride ion diffusion coefficient of the concrete which is added Na2 SO4 and mineral mixes is higher than the concrete which is added mineral mixes. In a certain scope of the mineral admixtures quantity, the frost - resistance of fly - ash concrete and slag concrete are good and the frost - resistance of Na2SO4 fly- ash concrete and Na2 SO4 slag concrete are better than datum concrete. But the NaESO4 causes the frost -resistance of concrete worse than the concrete which isnt added mineral admixtures.

关 键 词：掺合料 硫酸钠 冻融循环 Cl-扩散系数 早强剂 NEL法 

分 类 号：TB321[一般工业技术—材料科学与工程]