入模温度及引气剂含量对混凝土力学性能的影响  

Effect of mold temperature and air inducter content on mechanical properties of concrete

作　　者：张坤[1] 张戎令[1,2] 郭海贞 肖鹏震 王立博 窦晓峥 ZHANG Kun;ZHANG Rongling;GUO Haizhen;XIAO Pengzhen;WANG Libo;DOU Xiaozheng(Road and Bridge Engineering disaster Prevention and Control Technology National Local Joint Engineering Laboratory,Lanzhou Jiaotong University,Lanzhou 730070,China;Gansu Province Road Bridge and Underground Engineering Key Laboratory,Lanzhou Jiaotong University,Lanzhou 730070,China;China Railway 21 Bureau Group Co.,Ltd.,Lanzhou 730070,China;Gansu Changlong Highway Maintenance Technology Institute Co.,Ltd.,Lanzhou 730000,China)

机构地区：[1]兰州交通大学道桥工程灾害防治技术国家地方联合工程实验室,甘肃兰州730070 [2]兰州交通大学甘肃省道路桥梁与地下工程重点实验室,甘肃兰州730070 [3]中铁21局集团有限公司,甘肃兰州730070 [4]甘肃畅陇公路养护技术研究院有限公司,甘肃兰州730000

出　　处：《混凝土》2021年第12期36-39,共4页Concrete

基　　金：国家自然科学基金资助项目(51268032,51768033);青年人才托举工程(2015QNRC001);长江学者和创新团队发展计划滚动支持(IRT_15R29);甘肃省高校协同创新科技团队支持计划资助项目(2017C-08)。

摘　　要：为了研究入模温度和引气剂对混凝土抗压强度和微观孔结构的影响,进行了标准养护下5、10、15、20℃这4组入模温度和0、0.05%、0.10%、0.15%、0.20%这5组引气剂掺量下的强度试验,以及测试了28 d龄期下混凝土的微观孔隙结构。结果表明:28 d龄期时,入模温度从5℃提高到20℃时,混凝土的抗压强度提高了51.3%,入模温度提高加快了水泥的水化反应,改变了混凝土的密实性,提高了混凝土的抗压强度;与之相反,引气剂含量增加到0.20%时,混凝土的抗压强度下降了50.9%(入模温度为20℃),引气剂含量偏大时混凝土总孔隙率明显增加,密实性下降抗压强度降低。研究结果为掺入引气剂提高抗冻性的混凝土的设计提供参考。In order to study the effect of mold temperature and air-entraining agent on the compressive strength and microscopic pore structure of concrete,four groups of mold temperature,5,10,15,and 20℃,and 0,0.05%,0.10%,0.15%and 0.20%under standard curing were carried out.The strength test with five groups of air-entraining agents,and the micro-pore structure of concrete at the 28 days age were tested.The results show that at the 28 days age,the mold temperature was increased from 5℃to 20℃,the compressive strength of concrete increased by 51.3%,and the increase in mold temperature accelerated the hydration reaction of the cement,changed the compactness of the concrete,and increased the compressive strength of the concrete.In contrast,the air entrainer content increased to0.20%,the compressive strength of the concrete decreased by 50.9%(the mold temperature was 20℃).When the air-entraining agent content was too large,the total porosity of the concrete increased significantly,and the compactness decreased.The compressive strength was greatly reduced.The design of air-entraining concrete to improve frost resistance provides a reference.

关 键 词：混凝土 入模温度 引气剂 抗压强度 孔结构 

分 类 号：TU528.01[建筑科学—建筑技术科学]