考虑截面特性的预应力波纹腹板钢-混凝土组合梁抗火性能研究

The difference between prestressed composite beams with corrugated webs (PCBCWs) and conventional composite beams lies in applying prestress and variation of web from plate steel slab to corrugated webs in tension region of cross section. This variation can make the web thinner and can reach high height-thickness ratio. PCBCWs have been applied in large scale due to large flexural stiffness and great economical advantage. The project focuses on PCBCWs, with holes in the webs and concrete slab attached to the webs, and study their fire resistance. Evolution of loading carrying, flexural stiffness, evolution of stress in cable strands and pattern of failure are investigated. Also, the effect of concrete slab attached to webs on distribution of temperature in cross section, variation of stress in cable strands, and failure patterns, will be studied by using experiment, numerical simulation and theoretical derivation. Practical design method for PCBCWs, which will be referred and will promote application in engineering , will be developed based on parametric analysis and data fitting.

预应力波纹腹板钢-混凝土组合梁（PCBCW）,与传统组合梁区别在于对组合梁受拉区施加了预应力、并将平腹钢板改为波纹状钢腹板。这种创新可以使其腹板更薄，并能达到更大的高厚比。由于较大抗弯刚度及优良经济性能，该类组合梁在土木工程中得到了大量应用。本项目以PCBCW梁为研究对象，探索腹板开洞和腹板具有混凝土衬板的两类PCBCW组合梁抗火性能。研究腹板开孔对组合梁高温下承载力的演化规律、横向抗弯刚度、拉索张力退化与破坏形式的影响；探索混凝土衬板的存在对组合梁截面在火灾下温度分布及温度梯度、对拉索张力变化、PCBCW梁的挠度、及破坏规律与破坏机理的影响。采用试验研究、数值模拟、简化理论推导为手段研究其在火灾下承载能力及性能演化规律，探究其火灾下承载机理、破坏规律及失效机理。在参数敏感性分析基础上进行参数分析和数值拟合，提出PCBCW组合梁的实用抗火设计方法，为其抗火设计提供理论支撑，促进其工程应用。

预应力波纹腹板钢-混凝土组合梁（PCBCW）,与传统组合梁区别在于对组合梁受拉区施加了预应力、并将平腹钢板改为波纹状钢腹板。本项目以PCBCW梁为研究对象，探索了腹板开洞和腹板具有混凝土衬板的两类PCBCW组合梁抗火性能。研究了腹板开孔对组合梁高温下承载力的演化规律、横向抗弯刚度、拉索张力退化与破坏形式的影响；探索了混凝土衬板的存在对组合梁截面在火灾下温度分布及温度梯度、对拉索张力变化、PCBCW梁的挠度、及破坏规律与破坏机理的影响。采用试验研究、数值模拟、简化理论推导为手段研究了其在火灾下承载能力及性能演化规律，探究其火灾下承载机理、破坏规律及失效机理。在参数敏感性分析基础上进行参数分析和数值拟合，提出PCBCW组合梁的实用抗火设计方法，为其抗火设计提供理论支撑。