型钢混凝土异形柱-钢筋混凝土板节点冲切破坏机理及计算方法研究

Steel reinforced concrete (SRC) special shaped column – reinforced concrete (RC) slab structures have the advantages of combining the space utilization of floor plane and building elevation, structural high seismic behavior etc., so that thus are expected to have increased applications. However, research on the performance and design of such structure is still limited. The proposed research project will firstly research the connection patterns and measures of SRC special shaped column – RC slab connections, and punching tests on twenty-four specimens need to be performed under the column-top vertical loads. The inner force transferring path and failure mechanism will be revealed, and the gestating and developing of inner cracks and the pulse damage of connection core will be measured. Thus, the performance indices of these slab-column connections with different failures can be obtained to realize the parameters of theoretical calculation. Secondly, the refinement numerical model of SRC special shaped column – RC slab connections will be developed to simulate their whole punching mechanical loading process and get their vulnerable spot under various cases, so that the performance indicator database can be constructed by uniting the experimental results. Based on the philosophy of performance design, the punching damage quantitative indicators of SRC special shaped column – RC slab connections can be proposed by using the double standards of deformation and energy. According to the failure mechanism, the punching theoretical model can be derived by using the mechanical theory, and thus, the punching-shear strength theory and the reasonable link construction measures of SRC special shaped column – RC slab connections can be proposed under the conditions of compression-flexure-shear.

型钢混凝土异形柱-钢筋混凝土板结构融合建筑平面和建筑立面的空间利用率以及结构高抗震性能等优势，具有良好的应用前景。项目首先研发型钢混凝土异形柱-钢筋混凝土板节点的连接方式和构造措施，设计24个试件进行柱端竖向荷载作用下的冲切试验，揭示其内在传力路径和破坏机理，测试其内部裂纹的孕育和发展过程、节点核心的脉冲损伤，获取此类板柱节点不同破坏模式下受力性能指标，得到理论分析必要的计算参数。其次，开发型钢混凝土异形柱-钢筋混凝土板节点的精细化数值模型，对不同工况下此类板柱节点冲切受力全过程进行数值模拟分析并获取其受力薄弱环节，以此联合试验成果完成其性能指标数据库的建立。基于性能设计思想，采用变形和能量双重准则建立型钢混凝土异形柱-钢筋混凝土板节点冲切损伤量化指标；根据节点的破坏机理，利用力学原理推导其冲切受力的理论模型，提出压-弯-剪复合受力下节点的冲剪强度理论和合理的连接构造措施。

项目首先研发了内置钢环/埋设倒T形钢暗梁的型钢混凝土异形柱-钢筋混凝土无梁楼盖节点，极大提升了板柱节点抗冲切承载力和初始刚度；设计了16个试件进行柱端竖向荷载作用下的冲切试验，采用内置应变拉杆的测试手段捕捉了型钢混凝土异形柱-钢筋混凝土节点区混凝土拉应变，获取了冲切破坏面角度，为此类节点设计找准了计算依据；开发型钢混凝土异形柱-钢筋混凝土板节点的精细化数值模型，对不同工况下此类板柱节点冲切受力全过程进行数值模拟分析并获取其受力薄弱环节；建立了型钢混凝土异形柱-钢筋混凝土节点冲切荷载下损伤破坏的评估依据，基于各材料组分的抗剪贡献推导了冲剪作用下的极限承载力计算方法。