为了研究方钢管再生混凝土的界面粘结滑移性能,利用废弃混凝土作为再生粗骨料制作了10根方钢管再生混凝土短柱试件,并对其进行推出试验研究,试验中考虑了混凝土强度等级、埋置长度和再生粗骨料取代率3个变化参数的影响,获取了方钢管和再生混凝土界面之间的荷载一滑移曲线,分析了各变化参数对起滑粘结强度和极限粘结强度的影响。研究结果表明:方钢管再生混凝土荷载一滑移曲线大致经历了4个阶段,即无滑移阶段、应力上升阶段、应力突变阶段及应力下降阶段;取代率对起滑粘结强度和极限粘结强度的影响较小,但埋置长度较小试件的起滑和极限粘结强度比埋置长度较大试件的大;混凝土强度对其二者影响较大。
In order to study the interface bond-slip performance of recycled aggregate concrete-filled square steel tube ( RACFSST), ten specimens made from waste concrete were designed for tests. The parameters concerned were concrete strength grade, embedded length and recycled coarse aggregate replacement rate. The load-slip curves of square steel tubes and recycled aggregate concrete were obtained, and the influence of the parameters on starting bond strength and ultimate bond strength were analyzed. The results show that there were four stages in the load-slip curves of RACF- SST, including no-slip, stress rising, stress mutation and stress dropping. The replacement rate had a slight influence on the starting bond strength and ultimate bond strength, while the embedded length had the opposite effect. The specimens with shorter embedded length had larger bond strength. The concrete strength had a relatively large influence on them.