二次浇筑下钢混组合梁桥面板结合面受力分析及优化

Study on Stress Optimization of Secondary Pouring Interface of Bridge Deck of Steel-concrete Composite Beam

为明确钢混组合梁混凝土桥面板二次浇筑结合面性能并优化其受力特性,利用混凝土结合面剪切试验结果验证了数值模型计算方法的正确性,并通过试验及数值计算结果对比了一次浇筑与二次浇筑面结构受力性能差异,再结合工程实例对钢混组合梁混凝土桥面板二次浇筑结合面受力特性加以分析,并给出改善方法。试验及计算结果表明,二次浇筑界面抗剪能力下降,开裂荷载及极限抗剪荷载降低,而植筋与开槽可有效提高混凝土结合面抗剪性能,对于钢混组合梁,其存在多种新旧混凝土结合面,其受力与施工工序关系紧密,可以采用部分构件调整工序加植筋的方式,对受力较大的关键部位即新旧混凝土结合面性能加以改善。

To clarify the secondary pouring interface performance of concrete of steel-concrete composite beam and optimize its mechanical characteristics,the correctness of the numerical model calculation method is verified by the shear test results,and then the mechanical characteristics of concrete interface of steel-concrete composite beam are analyzed with an engineering example,and the improvement method is given.The results of experiment and calculation show that the interface shear capacity of secondary pouring decreases,and the planting bar can effectively improve the interface shear performance of new and old concrete.For steel-concrete composite beams,there are many interfaces between old and new concrete,and the interface stress is closely related to the construction process.The interface performance of the new and old concrete in the key parts with large stress can be improved by adjusting the process of some components and planting bars.