大型盘管试验前后混凝土工作性能变化及其机理分析  

Research on concrete before and after large coil puming test working performance change and mechanism analysis

作　　者：马建峰 袁达 李承洋 陈晓润 高达 吴雄 MA Jianfeng;YUAN Da;LI Chengyang;CHEN Xiaorun;GAO Da;WU Xiong(China West Construction Academy of Building Materials Co.,Ltd.,Chengdu 610015,China;China Construction Third Engineering Bureau Group Co.,Ltd.,Wuhan 430064,China)

机构地区：[1]中建西部建设建材科学研究院有限公司,四川成都610015 [2]中建三局集团有限公司,湖北武汉430064

出　　处：《混凝土》2023年第10期143-146,共4页Concrete

基　　金：国家自然科学基金青年基金(52002041)。

摘　　要：为研究超远距离泵送对新拌混凝土流变性及泵送性影响,测试了C30、C60和C80混凝土经大型盘管泵送前后工作性及流变性变化,并通过滑管仪预测了混凝土泵送压力。结果表明:泵送后混凝土扩展度减小,匀质性下降,且对高强度等级混凝土影响更加显著;混凝土在泵管中经剪切作用及水泥水化等影响,使泵送后混凝土屈服应力增加,塑性黏度减小,因而使得混凝土均匀性下降,V型漏斗流过时间减小;此外,通过滑管仪数据和Kaplan模型计算出的泵送压力较实际泵送压力大,表明滑管仪能较好的预测混凝土的泵送性能。In order to study the effect of ultra-long-distance pumping on the rheology and pumpability of fresh concrete,the changes of workability and rheology of C30,C60 and C80 concrete before and after pumping by long coil pipe were tested.And the concrete pumping pressure was predicted by the slide pipe rheometer.The results show that the slump of concrete decreases and the homogeneity decreases after pumping by the ultra-long coiled pipe,and this trend has a more significant effect on the high-grade concrete.Because the concrete is subjected to shearing and cement hydration in the pump pipe,the yield stress of the concrete increases and the plastic viscosity decreases after pumping.As a result,the uniformity of the concrete is reduced,and the flow time of the V-shaped funnel is reduced.In addition,the pumping pressure calculated by the slide pipe rheometer data and the Kaplan model is larger than the actual pumping pressure,which indicates that the slide pipe rheometer can better predict concrete and high pumping performance.

关 键 词：大型盘管泵送 流变性 泵送压力 滑管仪 

分 类 号：TU528.01[建筑科学—建筑技术科学]