关键词: 桥梁工程；钢拱桥；隔热涂层；施工控制；温度效应；有限元模拟

Abstract: During the construction stage, the large-segment steel arch rib is subjected to solar radiation, generating a non-uniform temperature field, which causes deformation of the closure section and makes closure process difficult. A thermal control method using coatings with different thermal properties in different zones was proposed to reduce the temperature difference and deformation. This method accurately simulated the three-dimensional temperature field under solar radiation by finite element software. And an area dividing method for the surface of bridges was proposed, and secondary development of the ABAQUS post-processing was conducted using the Python language to clarify the evaluation indicators and ultimately determine the optimized coating scheme for the arch ribs. The ABAQUS-FILM/DFLUX subroutine was used to simulate the three-dimensional temperature field over 24 hours, and the bridge surface was divided into 54 zones based on the angle of the surface normal vectors. Through the Python secondary development, a linear mapping between temperature data and coating radiation absorption rate was realized. It is concluded that at the most unfavorable moment, the partition range is decreased from 17.9 ℃ to 9.7 ℃, the standard deviation is decreased by 50.5%, and the maximum displacement of the closure section is reduced from 26 cm to 7.7 cm. The zonal coating strategy significantly mitigates the inhomogeneous temperature effect under solar radiation and provides technical support for the lifting of large-span sections without closure segments.

Key words: bridge engineering; steel arch bridge; thermal insulation coating; construction control; temperature effect; finite element simulation