摘要
采用P.O 42.5级水泥、高吸水性树脂、聚羧酸系高效减水剂、粉煤灰等原料配制了强度等级是C50的高流态泵送混凝土,浇筑成型后试块直接堆放在湿度为60%、平均温度为15℃的环境中进行了自然条件下的养护。试验分别测定新拌混凝土的坍落度和1 h坍损,以及不同龄期混凝土的力学性能,并利用SEM等方法对水泥石微观结构的进行了分析。试验结果表明,0.10%~0.14%掺量的高吸水性树脂能显著改善大掺量高效减水剂(掺量为1.0%时)引起的混凝土泌水和坍损过大的现象;且高吸水性树脂的掺入完全能实现混凝土在自养护条件下强度的发展,1 y龄期的、高吸水性树脂掺量0.18%以上的自养护试件强度可达85 MPa以上。SEM结果表明,高吸水性树脂吸水后呈胶态均匀分布在混凝土中,完全释水干燥后形成片状薄膜均匀分布在水化硅酸钙中。
C50 high flowing pump concrete was prepared by using the P. 0 42.5 cement, high water absorbent resin, polycarboxylate superplasticizer, fly ash and other raw materials. After pouring molding, the test blocks were stored directly under conditions of natural conservation which the humidity was 60% and the average temperature was 15 ℃. Slump of freshly mixed concrete, slump loss after lh, and the mechanical properties of concrete at different ages were tested. Cement microstructure were analyzed by SEM. The results show that 0. 10%-0. 14% volume of high water absorbent resin can significantly improve the phenomenon of concrete bleeding and excessive slump loss caused by the large amount of superplasticizer(when the dosage is 1.0% ). Concrete strength development was fully realized under self- curing conditions. At the age of ly, strength of the concrete which was added into 0.18% above volume of high water absorbent resin was more than 85 MPa. According to the results of SEM, high water absorbent resin was jelly in fresh concrete, and it would be form the sheet film which evenly distributed in the hydrated calcium silicate after completely releasing water.
出处
《硅酸盐通报》
CAS
CSCD
北大核心
2013年第4期623-629,共7页
Bulletin of the Chinese Ceramic Society
基金
河北省教育厅自然科学重点项目(ZD2010202)