新型梳齿榫型钢-混凝土组合梁桥设计方法研究——典型截面与节点承载能力

Novel Composite Dowels Steel-concrete Bridges'Structural Design Approach:Typical Section and Joint Bearing Capacity

为提出适用于快速施工的全预制梳齿榫型钢-混凝土组合梁设计方法。设计了其典型截面,对其抗弯承载能力和抗剪承载能力展开研究;分析了拉-剪耦合作用和箍筋配置对CL和PZ节点抗剪承载力的影响。结合AASHTO和欧洲规范,提出简化的极限抗弯承载力计算公式,基于混合截面原理提出组合梁桥的抗剪承载力计算公式,并对其进行准确性验证。发现拉拔效应会削弱节点的抗剪承载力,在相邻梳齿中应配置不少于2肢箍筋,CL节点的抗剪能力优于PZ节点。研究结果为这种新型结构总体设计提供理论依据。

To propose a design method for prefabricated composite dowel steel-concrete girders suitable for rapid construction,its typical cross-section,flexural and shear bearing capacity are studied.The effects of tension shear coupling and reinforcement configuration on the shear bearing capacity of CL and PZ joints were analyzed.Based on AASHTO and European standards,a simplified formula for calculating the ultimate flexural bearing capacity is proposed.A formula for calculating the shear bearing capacity is proposed based on the concept of hybrid steel-concrete cross section,and its accuracy is verified.It is found that the pull-out effect would weaken the shear bearing capacity of the joints.At least 2 stirrups should be installed in adjacent composite dowel,and the shear capacity of CL joints is better than that of PZ joints.The research results provide theoretical basis for the overall design of this new type of structure.