地裂缝对钢-混组合连续梁桥使用性能影响研究

Research on the Influence of Ground Fissures on Service Performance of Steel-Concrete Composite Continuous Beam Bridge

为了解地裂缝对钢-混组合连续梁桥使用性能的影响,以3跨变截面钢-混凝土组合连续梁为依托,建立有限元分析模型,根据桥梁设计基准期内地裂缝竖向沉降量预测值,研究了地裂缝对钢-混组合连续梁桥抗裂及变形2方面的影响。结果表明:1)地裂缝荷载效应增大了混凝土板开裂的宽度,但最大宽度远小于规范规定的裂缝容许值;2)当土体沉降量达到0. 097 m时,左边跨主梁跨中下挠值达到规范允许值0. 10 m。结论是地裂缝活动对钢-混组合连续梁桥混凝土板抗裂影响较小,而对变形影响显著。

In order to understand the influence of ground crack on the service performance of steel-concrete composite continuous beam bridge,a finite element model is established based on 3-span variable cross-section steel-concrete composite continuous beam.According to the predicted value of vertical settlement of ground fissure in the bridge design reference period,the influence of ground crack on crack resistance and deformation of steel-concrete composite continuous beam bridge is studied.The results show that:1)the load effect of ground crack increases the crack width of concrete slab,but the maximum width is far less than the allowable crack value specified in the code;When the soil settlement reaches 0.097 m,the midspan downwarping of the main beam of the left span reaches the allowable value of 0.10 m.The conclusion is that the ground crack activity has little effect on the crack resistance of concrete slab of steel-concrete composite continuous beam bridge,but has a significant effect on the deformation.