钢筋混凝土拱桥不对称T梁架设方案比选研究

Comparative Study on Asymmetric T-beam Erection Schemes for Reinforced Concrete Arch Bridges

摘要:

随着山区拱桥建设规模地不断发展，限于场地条件等因素限制，不对称施工方法的应用场景增多，需进一步开展不对称施工技术的研究。通过建立MIDAS有限元模型，结合实际钢筋混凝土拱桥项目，提出多种不同施加配重下的拱上T梁架设方案，并从强度、刚度及稳定性等方面，开展不同方案下的计算结果对比，并结合施工工效得出最优的施工方案。结果表明，不少于1跨的配重布置，可以有效降低钢筋混凝土拱桥T梁不对称架设时拱圈开裂的风险。综合施工工效及拱圈应力结果，以2跨配重布置为主，应力可降至1.4 MPa左右。配重的施加可以有效减小不对称施工下拱圈变形。

Abstract:

With the continuous development of mountain arch bridge construction scale, limited to site conditions and other factors, the application of asymmetric construction methods increases, and further research on asymmetric construction technology is needed. Through the establishment of MIDAS finite element model, combined with an actual reinforced concrete arch bridge project, a variety of T-beam erection schemes on the arch with different applied counterweights are proposed. The calculation results of different schemes are compared in terms of strength, stiffness and stability, and the optimal construction scheme is derived from the combination of construction efficiency. The results show that the counterweight layout of not less than 1 span can effectively reduce the risk of cracking of the arch ring in the asymmetric T-beam erection of reinforced concrete arch bridges. Based on the comprehensive construction efficiency and the stress results of the arch ring, with a two-span counterweight layout as the main approach, the stress can be reduced to approximately 1.4 MPa. The application of counterweight can effectively reduce the arch ring deformation under asymmetric construction.