高速公路路-桥过渡段桥头搭板受力研究  

Study on the stress of approach slab at bridgehead of expressway road-bridge transition section

作　　者：肖凯 崔伟[2,3] 黄伟[1] 孙勇 巩泽辉 XIAO Kai;CUI Wei;HUANG Wei;SUN Yong;GONG Zehui(Shandong Luqiao Group Co.,Ltd.,Jinan 250014,China;Geotechnical and Underground Engineering Research Institute,Shandong University,Jinan 250061,China;School of Qilu Transportation,Shandong University,Jinan 250002,China)

机构地区：[1]山东省路桥集团有限公司,山东济南250014 [2]山东大学岩土与地下工程研究院,山东济南250061 [3]山东大学齐鲁交通学院,山东济南250002

出　　处：《山东建筑大学学报》2024年第4期66-72,共7页Journal of Shandong Jianzhu University

基　　金：国家自然科学基金项目(52078278,52278358);山东省工业和信息化厅项目(202150100995)。

摘　　要：布设桥头搭板可有效解决路-桥过渡段差异沉降引起的桥头跳车问题。文章采用梁和地基支承刚度统一计算的有限元法确定搭板的设计参数,基于数值模拟方法研究了搭板在不同布设方案中的受力情况,确定了桥头搭板最易破坏的位置,明确了搭板的最优布设方案。结果表明:随着搭板厚度和长度的增加,搭板所受最大弯矩值增大,搭板末端越易产生集中应力,导致二次跳车问题,即搭板厚度和长度存在最优尺寸,搭板长度为10 m时,最佳厚度为0.35~0.45 m,而当搭板厚度为0.35 m时,其最佳长度为8 m;搭板与桥台铰接且深埋搭板有利于搭板的长期稳定;采用搭板可以有效避免桥头跳车问题,与常规搭板布设方案相比,深埋搭板布设方案所受的竖向压力、弯矩和挠度均有显著降低;搭板上部回填材料为水泥稳定级配碎石时,可以有效地改善搭板的承载性能。Approach slabs effectively mitigate the bump at the bridgehead issue caused by differential settlements at road-bridge transition sections.This study determines the design parameters of approach slab using the finite element method of unified calculation of beam and foundation bearing stiffness.Through numerical simulation,the study analyzes the stress distribution of approach slabs under various layout schemes,identifying the most vulnerable location and determining the optimal layout.The study shows that the maximum bending moment of the approach slab increases with its thickness and length,and the end of the approach slab is more prone to generating concentrated stress,leading to the problem of secondary bump at bridgehead,that is,there is an optimal size for the thickness and length of the approach slab,when the length of the board is 10 m,the best thickness is 0.35~0.45 m.However,when the thickness of the board is 0.35 m,the best length is 8 m;Articulated and deeply buried approach slabs are beneficial for the long-term stability of the approach slabs;The use of approach slabs can effectively avoid the bridge head jumping scheme,at the same time,compared with the conventional approach slabs layout scheme,approach slabs deep embedded layout scheme subjected to vertical pressure,bending moment and deflection are significantly reduced;When the backfill material on the upper part of the slab is cement stabilized graded crushed stone.

关 键 词：路-桥过渡段 桥头跳车 搭板最优尺寸 搭板受力 有限元法 

分 类 号：TU472[建筑科学—结构工程]