新型不等翼缘蜂窝梁组合扁梁及其梁柱节点的静力与抗震性能

Currently, exposed steel beams are an important constraint in the promotion of steel residential buildings. With exposed beams, floor height increases, coating costs increases, indoor visual effect decreases, and thus, promotion difficulty greatly increases. Therefore, learning from concrete slab-column structure, studying steel concrete composite slim floor has an important theoretical and practical value. From home and abroad, the asymmetric H-type composite slim floor’s static performance and fire resistance performance has a more systematic study, yet its joints’ seismic behavior is studied less. Besides, the common joint is complicated, less reliable, and still need improvement. A new type asymmetric castellated slim floor beams and beam-column connections is a patented new type steel concrete composite slim floor proposed to solve the above problems. It not only combines advantages of both the aforementioned flat beam and cellular beams, but also performs better. It greatly simplifies the connection, solving the composite slim floor connection difficulty and showing a broad application prospect, and currently related research has not been reported. This project will study the static and seismic behavior of the new type asymmetric castellated slim floor beams and beam-column connections with experiments, theoretical analysis and finite element simulations, and try to obtain the bearing capacity and stiffness of the asymmetric castellated slim floor beams at service and ultimate strength limit state and also propose seismic design methods of the connections.

目前制约钢结构住宅推广的一个重要因素是钢梁外露，钢梁外露加大了楼层高度、增加了包覆成本，同时影响室内观瞻，增加了推广难度。因此，借鉴混凝土板-柱结构特点，研究钢-混凝土组合扁梁楼盖具有重要的理论意义和实用价值。国内外针对不等翼缘H型钢组合扁梁的静力性能和抗火性能进行了较为系统的研究，但对节点抗震性能研究较少，且节点构造复杂、可靠性较差，尚需改进。新型不等翼缘蜂窝梁组合扁梁及其梁柱节点就是针对上述问题提出的一种具有自主知识产权的新型组合扁梁形式，兼具前述组合扁梁和蜂窝梁的优点，同时受力性能更好，且节点构造简单，解决了组合扁梁节点复杂的难题，应用前景广阔。目前相关研究尚未见报道。本项目将通过试验研究、理论分析和有限元模拟相结合的方法研究新型不等翼缘蜂窝梁组合扁梁及其梁柱节点的静力与抗震性能，得到正常使用和承载能力极限状态时新型扁梁的承载力和刚度计算方法；提出可供工程实用的节点抗震设计方法。

钢-混凝土组合扁梁楼盖通过将混凝土楼板搁置在钢梁的下翼缘来实现混凝土无梁楼盖效果。钢-混凝土组合扁梁楼盖能够有效降低结构层高，大幅提高钢结构的防火、防腐能力，有利于住宅空间的自由划分，因而在欧洲国家得到了广泛应用。.为解决焊接不等翼缘钢梁存在的焊接变形大、矫正困难等问题，提出了不等翼缘蜂窝梁组合扁梁的概念，以期节省用钢量，并使钢梁两侧混凝土能够通过钢梁腹板蜂窝孔贯通，增强钢梁与混凝土板的整体性。本项目的主要工作及成果如下：.（1）提出了楼板下承式不等翼缘蜂窝梁组合扁梁和双向叠合空心楼板组合扁梁两种不等翼缘蜂窝梁组合扁梁形式；提出了三种不等翼缘蜂窝梁的构造方法，给出了构造示例。.（2）进行了5个不等翼缘蜂窝梁组合扁梁试件抗弯性能试验研究。试验研究表明：不等翼缘蜂窝梁组合扁梁具有优良的延性性能，试验梁的挠跨比达到1/30时，荷载-跨中挠度曲线仍无下降趋势。腹板开蜂窝孔和开圆孔钢梁与混凝土楼板均能够共同工作，试件截面符合平截面假定。.（3）进行了不等翼缘蜂窝梁组合扁梁受弯性能理论分析，建立了能够考虑材料非线性和几何非线性影响的有限元模型，利用验证后的有限元模型分析了不等翼缘蜂窝梁组合扁梁的受力性能和工作机理。提出了不等翼缘蜂窝梁组合扁梁的承载力和刚度计算方法。.（4）进行了15个不等翼缘蜂窝梁组合扁梁梁柱节点抗震性能试验研究。考察了组合扁梁形式、柱轴压比、节点构造、梁板关系、开孔形式、剪力键布置等参数变化对节点抗震的性能。试验研究表明：不等翼缘蜂窝梁组合扁梁梁柱节点结合了纯钢梁梁柱节点和混凝土梁柱节点的优点，与混凝土板柱（无梁楼盖）节点相比，节点的承载性能和抗震性能均有较大提高和改善。.（5）进行了不等翼缘蜂窝梁组合扁梁梁柱节点抗震性能有限元参数分析。基于试验研究和有限元分析结果，提出了不等翼缘蜂窝梁组合扁梁梁柱节点抗震设计建议。