世构体系框架结构模型振动台试验研究

为了研究预制预应力混凝土装配整体式框架结构(世构体系)抗震性能，以某实际工程世构体系框架结构为原型，对其底部两层进行缩尺模型振动台试验研究。观察试验模型在不同振动工况下的损伤及破坏情况，对模型在各水准地震作用下的动力特性、加速度、位移、应变及扭转反应进行分析，并根据试验现象与试验结果，对世构体系框架整体进行抗震性能的综合评价。结果表明：该预制装配框架体系在多遇地震作用下未出现明显损伤，在罕遇地震作用下节点核心区未出现裂缝，模型仍能保持较好的整体性，抗震性能良好；试验模型结构布置合理，地震作用下主要运动形式为平动；罕遇地震作用下，模型自振频率最大降幅为21.89%，最大层间位移角为1/122；虽然模型存在一定程度的损伤，但其弹塑性层间位移角均小于GB 50011—2010《建筑抗震设计规范》中的限值，满足我国“小震不坏”、“大震不倒”的抗震设防目标。

Shaking table test on a frame structure model of SCOPE system

In order to study the seismic performance of frame structures comprised of precast prestressed concrete components (SCOPE system), a shaking table test was carried out on the two-story scaled frame structure at the bottom of a SCOPE system based on a practical engineering project. Damage phenomenon of the test model under different vibration conditions was observed. The dynamic properties, acceleration, displacement, strain and torsion response of the model corresponding to each seismic level were analyzed. According to the experimental phenomenon and results, the seismic performance of the whole frame of the SCOPE system was comprehensively evaluated. The results show that this kind of precast concrete frame has no obvious damage under the action of frequent earthquakes and has no cracks in the joint core area under the action of rare earthquakes, indicating that the model still has good integrity and seismic performance. Because of its reasonable structural arrangement, the main motion form of the test model is the translational motion. Under rare earthquakes, the maximum reduction of natural vibration frequencies of the model is 21.89%, and the maximum inter-story drift ratio is 1/122. Although the model has a certain degree of damage, the elastic-plastic inter-story drift ratios are smaller than the limit values of GB 50011—2010 ‘Code for seismic design of buildings’, which can satisfy the seismic precautionary requirements of ‘no damage under frequent earthquakes, no collapse under rare earthquakes’.