焊接锚垫板锚固区拉压杆模型及配筋设计

针对焊接锚垫板齿板锚固区配筋,提出了一种锚固区新型拉压杆模型。首先对齿板锚固区 6 种典型效应、主应力迹线以及力流平衡关系进行分析并建立新型拉压杆模型,其次通过美国国家公路与运输官员协会(American Association of StateHighway and Transportation Officials,AASHTO) Load-and-resistance Factor Design Bridge Design Specifications、Building Code Requirements for Structural Concrete and Commentary(ACI 318-19)、《公路钢筋混凝土及预应力混凝土桥涵设计规范》 ( JTG 3362—2018)和欧洲设计建议 Practical Design of Structural Concrete 进行拉压杆模型参数定量化设计,根据拉压杆几何关系推导出焊接锚垫板齿板锚固区劈裂力计算式,利用有限元分析,拟合出焊接锚垫板下齿板锚固区劈裂力合力重心计算式。 最后通过算例分析,按本文建议的拉压杆方法进行焊接锚垫板齿板锚固区结构配筋设计,能较好地控制锚下典型效应问题,相比《公路钢筋混凝土及预应力混凝土桥涵设计规范》(JTG 3362—2018)给出的设计方法,拉压杆模型法能较好地反映结构传力机制且具备可行性和可应用性,可为焊接锚垫板齿板锚固区配筋设计提供参考。

Strut-and-tie Model and Reinforcing Bars Design for the Anchorage Zone of Welded Bearing Plates

In response to the reinforcing bars design of the anchorage zone for welded bearing plates blisters, a novel Strut-and-tie model was proposed. Firstly, the analysis of six typical effects principal stress traces and force equilibrium relationships in the blisters anchorage zone was conducted and a new strut-and-tie model was established accordingly. Secondly, the parameters of the strut-and-tie model were quantitatively designed based on relevant design codes and recommendations from the American Association of State Highway and Transportation Officials (AASHTO) Load-and-resistance Factor Design Bridge Design Specifications, Building Code Requirements for Structural Concrete and Commentary(ACI 318-19), Specifications for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts (JTG 3362—2018), and European design recommendations Practical Design of Structural Concrete. A formula for calculating the splitting force in the anchorage zone of the welded bearing plates blisters was derived using the geometric relationship of the strut-and-tie model. Finite element analysis was employed to fit the formula and obtain the calculation formula for the center of splitting force in the anchorage zone of the welded bearing plates blisters. Finally, Through case analysis, the proposed strut-and-tie method was applied for the reinforcing bars design of the anchorage zone of the welded bearing plates blisters. It effectively controls typical effects in the anchorage zone and is comparatively safer than the design method provided by Specifications for Design of Highway Reinforced Concrete and Prestressed Concrete Bridges and Culverts (JTG 3362—2018) The strut-and-tie model method effectively reflects the structural force mechanism and is feasible and applicable, and can serve as a reference for the reinforcing bars design of the anchorage zone of the welded bearing plate blisters.