早强复合修补混凝土的制备及性能研究

选用硫铝酸盐水泥作为快速修补材料的主要胶凝材料,并以复合外加剂作为功能小料,通过系统试验制备了具有较高早期强度的早强复合修补混凝土,对其力学性能和收缩性能进行测试,并与C40普通混凝土进行对比。试验结果表明:早强复合修补混凝土的4 h强度已经达到了普通混凝土7 d的强度,1 d抗压强度已经达到其28 d抗压强度的80%以上;随着粉煤灰掺量的增加,混凝土的收缩率先减小后增大,当粉煤灰掺量为30%时,收缩率最小。

Study on preparation and properties of early-strength composite repair concrete

Using aluminum sulphate cement as the main cementitious material for rapid repair material,and using composite admixture as a small functional material,early strength composite repair concrete with high early intensity was prepared through systematic test.Its mechanical properties and shrinking properties were tested and compared with C40 ordinary concrete.The test results show that the 4 h strength of the early strength composite repair concrete has reached 7 d strength of ordinary concrete,1 d compressive strength has reached more than 80%of its 28 d compressive strength,and the concrete shrinkage rate is reduced first and then increased with the increase of fly ash content.When the content of fly ash is 30%,the shrinkage is minimal.