摘要
选取粉煤灰混凝土龄期为7d、14d、28d、60d、90d、180d和360d,对钢筋与施工期粉煤灰混凝土的黏结性能进行了拉拔试验,分析了黏结性能随龄期的变化规律。结合已有的试验结果进行统计分析,提出了粉煤灰混凝土早期黏结强度的计算式,建立了粉煤灰混凝土早期的黏结-滑移本构关系。研究结果表明:随着混凝土龄期的增长,自由端开始滑移时的荷载也随之增大,加载端、自由端滑移均减小,加载端钢筋应变增大,钢筋应变沿黏结长度的分布曲线变陡,黏结应力峰值增大;与已有研究结果相比,黏结强度计算式误差为10%～25%,黏结-滑移本构关系计算式在滑移1.0 mm以内接近,而滑移超过1.0 mm则误差较大。
Seven concrete ages such as 7-day, 14-day, 28-day, 60-day, 90-day, 180-day and 360-day were selected to study the bond performance of reinforcement and early-age fly ash concrete during construction through pull-out tests. The relationship of bond performance and concrete bond strength formula of early-age fly ash concrete was p age was analyzed. Based on the test results of literature, the roposed and the bond-slip constitutive relation of early-age fly ash concrete was established. The results show that： with growth of concrete age, the load corresponding to the free end slip increases while the amount of slips at loading end and free end decrease. The rebars strain at the loading end increases. The distribution curve of rebars strain along anchor length in bond zone becomes steep. The peak of bond stress distribution curve increases. Compared with the results of previous studies, is about 10% to 25% , the bond-slip constitutive relation is close when the slip is the calculation error of bond strength within 1.0 mm while the calculationerror is larger when the slip is more than 1.0 mm.
出处
《建筑结构学报》
EI
CAS
CSCD
北大核心
2013年第4期152-157,共6页
Journal of Building Structures
基金
国家杰出青年科学基金项目(50725824)
国家"十一五"科技支撑项目(2006BAJ03A02-03)
陕西省自然科学基金项目(2012JQ7020)
