新拌湿喷混凝土内聚力测试与影响因素分析  

Test Cohesion and Influence Factors Analysis of Fresh Wet-mix Shotcrete

作　　者：何文敏[1,2] 陈华鑫[3] 李祖仲[3] 盛燕萍[3] 关博文[3] 

机构地区：[1]陕西铁路工程职业技术学院,渭南714000 [2]陕西省高性能混凝土工程实验室,渭南714000 [3]长安大学材料科学与工程学院,西安710064

出　　处：《硅酸盐通报》2015年第9期2725-2730,共6页Bulletin of the Chinese Ceramic Society

基　　金：陕西省教育厅自然科学基金专项(2013JK0933);国家自然科学基金资助(51208047);国家自然科学基金项目(51308062)

摘　　要：新拌湿喷混凝土内聚力是决定湿喷混凝土一次喷射厚度的关键因素。设计直剪试验,采用正交试验方法分析了新拌湿喷混凝土内聚力影响因素,结果表明:新拌混凝土内聚力与流动性线性负相关性显著;影响新拌湿喷混凝土内聚力的因素排序为砂率>速凝剂掺量>粉煤灰掺量>水胶比。砂率由50%增大到70%时,新拌混凝土内聚力逐渐降低;水灰比从0.4增大至0.5时,新拌混凝土内聚力先增大、后减小;粉煤灰掺量不超过20%时,可提高新拌混凝土内聚力;新拌混凝土内聚力随速凝剂掺量增大,超过最佳掺量后新拌混凝土内聚力增值微小。The cohension of fresh wet-mix shotcrete is the controllable factor for build-up thickness. The direct shear testing method is put followed and the influence factors of cohesion are analyzed by orthogonal testing method. It shows that the linear interrelation between the fluidity of fresh concrete and cohesion is obvious negatively and the primary and secondary factors affecting cohesion of fresh concrete are founded. The sand percentage is one of the most important factors affecting cohesion of fresh concrete, secondly, the content of accelerating agent, thirdly, the content of fly ash and lastly water-binder ratio. When the sand percentage is from 50% to 70%, the cohesion of fresh concrete reduces gradually. When water-binder ratio is from 0.4 to 0.5, the cohesion of fresh concrete at first increases then decreases. When the amount of fly ash replaces the cement no more than 20% by weight, it will help to improve the cohesion of fresh concrete. And the cohesion of fresh concrete increases with the increase of accelerating agent, but it increases little when the accelerating agent content exceeds the optimum value.

关 键 词：湿喷混凝土 新拌混凝土 内聚力 直剪法 

分 类 号：TU528[建筑科学—建筑技术科学]