型钢组合梁桥合理跨径及性能试验研究

Study on Reasonable Span and Performance Test of Section Steel Composite Beam Bridge

为确定梁高大于700 mm的H型钢组合梁的适用跨径,对实际工程结构设计与应用提供理论依据及参考,以每平方米用钢量与控制应力为指标,进行H型钢组合梁合理跨径的数值理论研究。同时依托实际工程对H型钢组合梁进行现场性能试验,把握结构在施工与加载情况下的挠度变形与应力状态,检验理论模型的有效性。研究结果表明,不同型号下H型钢组合梁的最大适用跨径在19~27 m,且在桥宽相同及满足控制指标的情况下,梁高越高所需的用钢量越小。加载过程中,H型钢组合梁的跨中挠度与最大应力都相对较小,结构刚度较大,安全可靠;卸载过程中,变形与应力都能很好地恢复至上一状态,结构仍处于弹性阶段。

To determine the applicable span of H-section steel composite beam with the height greater than 700 mm, the theoretical basis and reference are provided for the design and application of the actual engineering structure. Taking the quantity of steel per square meter and the control stress as the indicators, the numerical theoretical study of the reasonable span of H-section steel composite girder is carried out. At the same time, the field performance test is implemented for the H-section steel composite girder based on the actual projects to grasp the deflection deformation and stress state of the structure under the construction and loading, and to validate the effectiveness of the theoretical model. The results of the study show that the maximum applicable span of H-section steel composite girder with the different types is 19~27 m. The higher the girder height, the smaller the amount of steel required under the condition of the bridge width same and meeting the control indicators. During the loading process, the midspan deflection and the maximum stress of the H-section steel composite girder are relatively small,and the structural rigidity is relatively large, which proves that the structure is safe and reliable. During the unloading process, the deformation and stress can be well restored to the previous state, and the structure is still at the elastic stage.