键槽装配式拼缝受剪性能试验研究与理论分析

EXPERIMENTAL RESEARCH AND THEORETICAL ANALYSIS OF POLYGON-KEY ASSEMBLY CONNECTION

为了提高装配式RC剪力墙结构中装配式拼缝的受剪性能,提出新型键槽装配式拼缝。开展键槽装配式拼缝的受剪性能试验研究,研究不同的键槽倾角、键槽高度和轴压比对其承载力和刚度的影响,进而揭示其失效破坏模式。在此基础上,对键槽装配式拼缝的受力性能进行理论分析,推导其相应的承载力计算理论公式,并利用试验结果对理论分析结果的有效性进行验证。研究结果表明,键槽的设置能够有效提高装配式拼缝的抗剪承载力,与平行装配式拼缝相比,键槽装配式拼缝的峰值荷载提高百分比大于15%。当键槽倾角在45°~90°范围内时,键槽可以有效提高键槽装配式拼缝的峰值荷载,且设置不同键槽倾角的键槽装配式拼缝的峰值荷载相差不多。随着键槽高度的增大,键槽装配式拼缝的开裂荷载和峰值荷载均略有提高,当键槽高度在5 cm~7 cm范围内时,键槽装配式拼缝的峰值荷载相差不多。随着轴压比的增加,键槽装配式拼缝的峰值荷载逐渐增加。基于剪切-摩擦理论建立的键槽装配式拼缝峰值荷载的计算公式,理论公式计算值和试验值吻合较好。

To improve the shear performance of assembly connections in precast RC shear wall structures,a novel polygon-key assembly connection(PKA connection)is proposed.Pseudo-static tests are carried out to study the shear performance of the PKA connections.Specimens’parameters considered in the tests consist of polygonkey inclination angles,polygon-key heights and axial compression ratios.Shear capacity,stiffness,and failure mode of the PKA connections are investigated.Furthermore,theoretical analyses of the PKA connections are performed,equations for calculation of PKA connections’shear capacity are deduced,and the theoretical analysis results are validated by the test results.The results show that the polygon-keys can effectively improve shear capacity of the PKA connections.Compared with parallel assembly connections,peak loads of the PKA connections are enhanced by more than 15%.When polygon-key inclination angles are within the range of 45°~90°,peak loads of the PKA connections change slightly.When polygon-key heights are within the range of 5 cm~7 cm,cracking loads and peak loads of the PKA connections change slightly.With an increase in the axial compression ratio,peak loads of the PKA connections gradually increase.Based on the shear-friction theory,calculated peak loads of the PKA connections are in good agreement with the test results.