新老碾压混凝土粘结强度的影响因素分析  

Influencing Factors of Bond Strength of New and Old RCC

作　　者：吴冠宇 董政良 余志坚 郑刚峰 张晓飞[2] WU Guanyu;DONG Zhengliang;YU Zhijian;ZHENG Gangfeng;ZHANG Xiaofei(Shaanxi Water Conservancy and Hydropower Engineering Consulting Center,Xi'an,Shaanxi 710109,China;School op Water Resources and Hydro-Electric Engineering,Xi'an University op Technology,Xi'an,Shaanxi 710048,China;Zhejiany Survey and Design Institute oo Water Resources and Hydroocmer,HangZhou,Zhejiany 310000,China)

机构地区：[1]陕西省水利水电工程咨询中心,陕西西安710109 [2]西安理工大学水利水电学院,陕西西安710048 [3]浙江省水利水电勘测设计院,浙江杭州310000

出　　处：《水利与建筑工程学报》2023年第6期136-142,共7页Journal of Water Resources and Architectural Engineering

基　　金：国家自然科学基金(51479168);陕西省水利厅科技计划项目(2020slkj-12)。

摘　　要：为了探究影响新老碾压混凝土粘结强度的因素,以新老混凝土为研究对象,采用标准的混凝土试块边长为150 mm立方体试件,强度等级分别为C20、C30、C40的新碾压混凝土和强度等级为C30的老碾压混凝土试件,以新老碾压混凝土所使用水泥净浆及不同掺比的固结剂(HEC)作为界面剂,对试件进行劈拉试验,得出粘结强度随新碾压混凝土强度等级及HEC界面剂掺量变化的规律,并且建立新老碾压混凝土粘结模型,对模型施加一定的荷载进行计算,以试验数据为基准与模拟仿真值进行对比验证。结果表明:在一定范围内新老混凝土粘结劈拉强度随着新混凝土强度的增大而增大,但增大的程度不明显,而随着HEC界面剂掺量的增加,其粘结强度逐渐增大,但过大的HEC界面剂掺量反而会使粘结强度降低:40%>50%>30%>20%>10%>水泥净浆。The bonding quality of concrete surface is the key of engineering repair and reinforcement,which determines the success or failure of engineering repair and reinforcement.In order to explore the factors affecting the bond strength of new and old RCC,150mm cube specimens were designed with new and old concrete as the research object.The new RCC specimens with strength grades of C20,C30 and C40 and the old RCC specimens with strength grades of C30,respectively,and the cement paste and mixing ratio used for new and old RCC were as follows:10%,20%,30%,40%HEC reagent was used as the interface agent,and the splitting test was carried out on the specimen.The law of bond strength change with the strength grade of new RCC and the content of HEC interface agent was obtained.In addition,the bond model of new and old RCC was established,and a certain load was applied to the model for calculation.The test data is compared with the simulation value.The results show that the bond splitting tensile strength of new and old concrete increases with the increase of new concrete strength,but the degree of increase is not obvious,and with the increase of HEC interfacial agent content,the bond strength increases gradually,however,excessive amount of HEC interfacial agent will reduce the bonding strength:40%>50%>30%>20%>10%>cement paste.

关 键 词：碾压混凝土(RCC) 粘结强度 水泥净浆 劈拉试验 HEC界面剂 数值模拟 

分 类 号：TV698.2[水利工程—水利水电工程]