Structural Performance of Concrete-filled Rectangular Steel Tubular Joints with Perfobond Rib in Bridges using Damage Model
Structural Performance of Concrete-filled Rectangular Steel Tubular Joints with Perfobond Rib in Bridges using Damage Model
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DOI：
10.1061/9780784478530.006
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发表时间：
2014-06
期刊：
影响因子：
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通讯作者：
Z. Xiong;Yongjian Liu;Ning Zhang;S. Song
中科院分区：
文献类型：
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作者：
Z. Xiong;Yongjian Liu;Ning Zhang;S. Song
组合管桁桥以其施工周期短、力学性能优良等优点在公路工程中得到了广泛的应用。结合桁架桥节点的形状和变形是其关键。钢管混凝土相贯节点是提高钢管混凝土节点承载力的有效途径。而矩形钢管与混凝土之间的粘结力分布不均匀，会导致钢管内混凝土的粘结滑移。为了提高界面结合强度，在接头处的管内设置了开孔筋。本文通过实验标定和数值模拟的方法，对钢管混凝土连接件和带开孔肋钢管混凝土连接件的损伤机理进行了研究。提出了一种基于应力修正断裂应变模型的钢节点损伤与断裂评估新方法。同时考虑临界断裂应变和应力三轴度的损伤模型通过实验进行了标定，验证了模型的准确性。利用商业软件ABAQUS提供的用户子程序工具建立了损伤模型。通过对CFTJ和带开孔肋CFTJ的分析，发现带开孔肋CFTJ对混凝土的约束能力比CFTJ高得多。本文还比较了两种节点破坏机理的差异。
A composite tubular truss bridge has been widely used in highway projects since its short construction period and excellent mechanics characteristic. The joint’s configuration and deformation of the composite truss bridge are of vital importance. Concrete filled tubular joint (CFTJ) has been approved as an effective way to enhance the loading capacity. While the bonding force between concrete and rectangular tube is not distributed uniformly, which will cause the bond-slip behavior in the tube. To improve the interface bonding strength, perfobond rib is installed inside tube on the joint. The paper represents the damage mechanism both CFTJ and CFTJ with perfobond rib through experiment calibration and numerical methods. The author proposes a new method to evaluate the steel joint’s damage and fracture based on the stress-modified fracture strain model. The damage model which considers both critical fracture strain and stress triaxiality is calibrated by experiment to validate its accuracy. The user subroutine tool provided by commercial software ABAQUS is implemented to establish the damage model. Through analysis of CFTJ and CFTJ with perfobond rib, CFTJ with perfobond rib is found to have considerably much high constraint capability to concrete than CFTJ. The damage mechanism difference of the two types of joints is also compared in the paper.