掺混合材和硫酸钠水泥石可溶出Na^+的实验  

The Study on Dissolvable Na^+ of Added Mineral Admixture and Sodium Sulfate Hydrated Cement Paste

作　　者：张巨松[1] 韩自博[1] 赵勇 邓嫔[1] 张微[1] 聂治平[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 [2]辽宁瑞丰混凝土有限公司,辽宁沈阳110035

出　　处：《沈阳建筑大学学报（自然科学版）》2010年第3期522-527,共6页Journal of Shenyang Jianzhu University：Natural Science

基　　金：住房和城乡建设部科技攻关项目(2007-k4-19);沈阳地铁混凝土攻关项目(SW06-08-30)

摘　　要：目的分析在掺加Na2SO4后,粉煤灰、矿粉、水泥以及不同粉煤灰、矿粉掺量的水泥石中不同水化龄期的可溶出Na+量,进而研究Na+对混凝土的潜在破坏性.方法利用溶出法对不同水化龄期样品进行处理,再利用离子选择性电极法对样品中的可溶出Na+量进行化学分析,以此来研究对水泥石仍有影响的Na+量随水化龄期的变化.结果 Na2SO4掺量超过2%时,水化早期的可溶出Na+量有较大幅度的提高;在水泥、粉煤灰和矿粉中,固化Na+量最大的是粉煤灰;Na2SO4掺量2%时,胶凝材料中掺入粉煤灰可明显降低可溶出Na+量,胶凝材料中矿粉掺量越高可溶出Na+量越高.结论使用Na2SO4时,应将用量控制在2%以下;水泥中复合粉煤灰可显著提高固化Na+的能力,粉煤灰的适宜掺量为30%;水泥中复合矿粉会降低固化Na+的能力.To study the latent destructiveness of Na ＋ to the concrete,this paper analyzes the dissolvable Na ＋ in the hydrated paste of the fly-ash,pulverized slag,cement as well as cement which mixed with different quantity fly-ash or pulverized slag after added Na2SO4 of different hydrated period.To investigate the change of the dissolvable Na ＋ quantity in different hydrated period,the ex-situ leaching method is used to deal with the different hydrated period sample,and then the ion-selective-electrode method is used to carry on chemis-try analysis on the quantity of dissolvable Na ＋.The quantity of dissolvable Na ＋ in the hydrated cement paste of the earlier hydrated period raise significantly when the amount of Na2SO4 is over 2%;amount cement,fly-ash and pulverized slag,the most fix Na ＋ is fly-ash;when the amount of Na2SO4 is 2%,add fly-ash in the colloidal material can lower the quantity of dissolvable Na ＋ obviously,however,the dissolvable Na ＋ quantity in the hydrated paste is increase along with the pulverized slag quantity increasing.So the amount of Na2SO4 should be under 2% when used in the concrete.The ability of fix Na ＋ raise significantly when cement com-pound fly-ash,and the proper quantity of fly-ash is 30%;But the ability of fix Na ＋ decrease when cement compound pulverized slag.

关 键 词：水泥石 可溶出Na+ 粉煤灰 矿粉 NA2SO4 

分 类 号：TB321[一般工业技术—材料科学与工程]