关键词: 桥梁工程；劲性骨架混凝土拱桥；正交试验；极差分析；方差分析；稳定性

Abstract: To investigate the stability performance of super-long span rigid skeleton concrete arch bridges, the Tian’e Longtan Bridge was taken as the engineering background, the trail designs of three kinds of super-long span (750 m, 850 m, and 950 m) rigid skeleton concrete arch bridges were conducted according to actual bridge site terrain conditions. Through the orthogonal experimental design combining with range analysis and ANOVA methods, the influence patterns of various parameters on arch bridge stability were systematically studied. An innovative “工”-shaped concrete cross brace was proposed, which was compared with the traditional “I”-shaped, “K”-shaped and “米”-shaped cross braces. The research results demonstrate that: the height-to-span ratio at the crown serves as the critical control factor for in-plan stability, while out-of-plan stability is jointly influenced by the width-to-span ratio and the upper flange width of the “工”-shaped brace. The novel “工”-shaped brace achieves coordinated optimization of in-plan and out-of-plan stability through flange width adjustment, and its out-of-plan stability bearing capacity has an significant improvement compared to those of conventional configurations. The “工”-shaped concrete cross brace exhibits superior resistance to out-of-plan instability and economic efficiency compared to traditional solutions, providing a novel technical approach for super-long span arch bridge design.

Key words: bridge engineering; rigid skeleton concrete arch bridge; orthogonal experiment; range analysis; variance analysis; stability