摘要
为研究圆钢管再生混凝土界面黏结的失效机理,以再生粗骨料取代率、混凝土强度等级及长径比为变化参数,设计了4组共15个圆钢管再生混凝土试件进行推出试验。通过试验获取了界面黏结的荷载-滑移曲线、黏结应变和黏结力分布规律。运用相关计算模型对圆钢管再生混凝土的黏结强度进行对比计算,回归得到圆钢管再生混凝土的黏结强度计算式。研究结果表明:加载端首先出现滑移,此后滑移发展至自由端;在加载初期和加载后期的圆钢管纵向应变分别呈负指数分布和线性分布;长径比较大试件的峰值荷载均大于长径比较小的试件;界面黏结损伤的发展随再生粗骨料取代率的增加而提前;界面埋置长度的增加有利于其黏结滑移能量耗散。
In order to reveal the interaction failure mechanism of bond performance at the interface of recycled aggregate concrete filled circular steel tubes（RACFCST）,a total of 15 RACFCST short column specimens were designed for push-out test.Three test parameters of replacement rate of recycled coarse aggregate（RCA）,concrete strength grade and length to diameter ratio were considered to research their influences on bond behavior of RACFCST.Load-slip curves,distribution laws of bond strain and bond load for RACFCST specimens were obtained.For contrastive computation,practical formulas for bond strength of concrete filled steel tube（CFST） were used to calculate that of the RACFCST.The regression bond strength formula was put forward.The results show that the initial slip at the loading end develops earlier than that at the free end.The longitudinal strains of steel tube in the early and late loading stages respectively exhibit a negative exponent distribution and linear distribution.Along with the increasing of the ratio of length to diameter,the bond load of RACFCST will be increased to some extent.The development of interfacial bond damage can be advanced with the increasing of RCA replacement rate.At the same time,energy dissipation of bond slip is much better along with the increasing of interface embedded length.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2013年第7期148-157,共10页
Journal of Building Structures
基金
国家自然科学基金项目(50908057
51268004)
广西自然科学基金项目(2012GXNSFAA053203
2013GXNSFDA019025)
广西科技攻关项目(桂科攻12118023-3)
广西理工科学实验中心重点项目(LGZX201102)
关键词
圆钢管再生混凝土
推出试验
黏结强度
损伤
耗能
recycled aggregate concrete-filled steel tube
push-out test
bond strength
damage
energy dissipation
