现行规范下对再生混凝土梁裂缝宽度的试验研究  

Experimental research on crack width of recycled concrete beams under current norm

作　　者：柏茜 刘波[1] 张郑贤 姜新佩[2] BAI Xi;LIU Bo;ZHANG Zhengxian;JIANG Xinpei(School of Water Conservancy and Hydroelectric Power,Handan 056038,China;College of Civil Engineering,Hebei University of Engineering,Handan 056038,China;School of Water Conservancy and Hydropower,Wuhan University,Wuhan 430072,China)

机构地区：[1]河北工程大学水利水电学院,河北邯郸056038 [2]河北工程大学土木工程学院,河北邯郸056038 [3]武汉大学水利水电学院,湖北武汉430072

出　　处：《混凝土》2021年第10期138-142,共5页Concrete

基　　金：国家重点研发计划项目(2018YFF0300201)。

摘　　要：通过对不同取代率、不同钢筋型号和不同配筋率的再生混凝土梁进行裂缝宽度试验研究,得到再生骨料取代率对裂缝宽度并无明显影响,但随着钢筋强度的增加而减小,随着配筋率的增加而增大。将试验结果与现行的3种中国规范进行对比验证,得到当取代率小于30%时,适宜采用规范二计算再生混凝土最大裂缝宽度,当取代率在30%~50%之间时,适宜采用规范一,当取代率大于50%时,适宜采用规范三。根据不同保证率规范下裂缝宽度计算分析,得到规范一在80%保证率最接近真实值,规范二在90%的保证率下最接近真实值,规范三在70%保证率下接近真实值,此3种情况可以作为相应规范的保证率,既能满足结构安全设计又能保证经济性。修正后的计算式的计算误差基本小于修正前的。Through the experimental study on the crack width of recycled concrete beams with different substitution rate,different reinforcement type and different reinforcement ratio,the experimental results are obtained,and the results are verified and explained under the current three specifications.The results show that the replacement ratio of recycled aggregate has no obvious influence on the crack width,but decreases with the increase of reinforcement strength and increases with the increase of reinforcement ratio.When the substitution rate is less than 30%,it is suitable to use standard two to calculate the maximum crack width of recycled concrete.When the substitution rate is between 30%~50%,it is suitable to adopt the standard one.When the substitution rate is greater than 50%,it is suitable to adopt the standard three.According to the calculation and analysis of the crack width under the standard of different guarantee rate,the standard one at 80%guarantee rate is closest to the real value,the standard two is the most close to the real value under the guarantee rate of 90%,the standard three is close to the real value under the 70%guarantee rate.The three conditions can be used as the guarantee rate of the corresponding standard,which can not only satisfy the structural safety design but also guarantee the economy.The calculated error of the modified formula is basically less than that before correction.

关 键 词：现行规范 再生混凝土梁 裂缝宽度 保证率 高强钢筋 

分 类 号：TU528.01[建筑科学—建筑技术科学]