均布荷载下预应力FRP布钢与混凝土组合梁变形计算

The Deformation Calculation Formulas of Prestressed FRP Sheets Steel-Concrete Composite Beam under Uniformly Distributed Load

目的为提高预应力组合梁的承载力和刚度,将传统预应力技术与FRP加固技术相结合,形成预应力FRP布钢与混凝土组合梁.方法根据预应力FRP布钢与混凝土组合梁结构与受力特征,利用弹性理论,对其进行分析.结果建立其考虑交接面相对滑移和预应力FRP布内力增量影响的组合梁变形微分方程,给出均布荷载作用下的组合梁变形理论计算公式.结论计算结果证明,预应力FRP布内力增量对组合梁变形影响相对较小,从而给出了组合梁变形的简化计算公式;所建立的预应力FRP布钢与混凝土组合梁变形理论计算公式具有合理性.

The design characteristics of steel-concrete composite beams can be enhanced significantly by epoxy bonding fiber reinforced polymers（FRP ） sheets to the critically stressed tension areas and it can exert high strength in FRP effectually, decrease the bending deformation of steel-concrete composite beams and improve the bending performance in the regular service course. According to the structure and bearing characteristics, the deformation differential equations considering the effect of interface slip and internal force increment were established based on elasticity theory. Deformation calculation formulas in different cases were presented. The test results show that the effect of prestressed FRP sheets internal force increment to composite beam deformation was much less, so it could be ignored. The reduced equation （Formulas） of deformation on prestressed FRP sheets steel-concrete composite beam were established.