论文部分内容阅读
为掌握预应力钢箱高强混凝土组合梁的受扭性能,以箍筋间距和预应力等级为主要参数设计了3根足尺试验梁,在自行研制的扭转试验装置上进行试验,得到了试验梁的扭矩-扭率曲线、钢筋扭矩-应变曲线、钢梁及混凝土应变分布等重要参数,对破坏形态与工作机理进行了详细分析。采用预应力影响系数,推导出了该类组合梁的开裂扭矩计算公式;基于变角空间桁架模型理论,推导出了极限扭矩计算公式,并将计算值和实测值进行了对比分析。结果表明:计算值与试验值吻合良好;受扭承载力由混凝土翼板和钢箱梁组成的箱形梁承担;预应力等级对试验梁开裂扭矩影响明显,而箍筋间距和预应力等级对试验梁极限抗扭承载力影响不大。
In order to grasp the torsional behavior of prestressed steel-concrete composite high-strength concrete beams, three full-scale test beams were designed by taking the stirrup spacing and pre-stress level as the main parameters. The test beam was tested on the self-developed torsion test device and the experimental beam Torque - torsion curve, torsional moment - strain curve of steel bar, strain distribution of steel beam and concrete, etc., The damage form and working mechanism are analyzed in detail. Based on the theory of space truss model, the formula of ultimate torque is deduced, and the calculated value and the measured value are contrastively analyzed. The results show that the calculated values are in good agreement with the experimental values. The torsional load bearing capacity is assumed by the box girder composed of concrete flange and steel box girder. The prestressing grade has obvious influence on the cracking torque of the test beam, while the stirrup spacing and prestressing grade Experimental beam ultimate torsional bearing capacity has little effect.