Experimental study on deformation characteristics of ballastless tracks under downward bending deformation of long-span cable-stayed bridge. (1st May 2020)

• Record Type: Journal Article
• Authors: Zheng, Weiqi; Sheng, Xingwang; Zhu, Zhihui; He, Hongqiang
• Is Part Of: Engineering structures. Volume 210(2020)
• Publication Date: 2020-05-01
• Subjects: Long-span cable-stayed bridge -- Downward bending deformation condition -- Ballastless track -- Interlayer -- Deformation characteristics -- Isolation layer -- High-speed railway; Structural engineering -- Periodicals; Structural analysis (Engineering) -- Periodicals; Construction, Technique de la -- Périodiques; Génie parasismique -- Périodiques; Pression du vent -- Périodiques; Earthquake engineering; Structural engineering; Wind-pressure; Periodicals; 624.105
• DOI: 10.1016/j.engstruct.2020.110363
• Languages: English
• ISSNs: 0141-0296

Abstract

Highlights: Unit-plate ballastless track can be used to pave on long-span cable-stayed bridge. The interlayers of ballastless track experience compressive or tensile deformation. Rubber isolation layers improve the mechanical behaviors of ballastless tracks. Voids can be created in ballastless tracks with geotextile isolation layers. Voids were hardly created in ballastless tracks with rubber isolation layers. Abstract: Laying ballastless tracks on long-span cable-stayed bridges is a new attempt. This has become an obstacle to the development of high-speed railway technology, which needs further research. The deformation characteristics of ballastless tracks are affected by the behaviors of long-span cable-stayed bridges. Meanwhile, the deformation conditions of long-span cable-stayed bridges also impose higher requirements for ballastless tracks. In this work, a segmental model was developed in laboratory, on which various types of ballastless tracks were paved. Based on this, the maximum downward bending deformation condition of a long-span cable-stayed bridge was obtained to investigate the deformation characteristics of ballastless tracks. The obtained experimental results indicated that interlayer deformation and pressure were linearly increased with the increase of test load. Moreover, the interlayers of ballastless tracks with EPDM isolation layer are always in a state of compression due to the pre-compressions of EPDM isolation layer produced in construction stage. However, interlayer defects are formed at the ballastless tracks with geotextile isolation layers, which can affect their durability and reliability. Therefore, reasonable arrangements of isolation layer highly coordinated deformations between long-span cable-stayed bridges and ballastless tracks. It should be noted that the feasibility of laying ballastless tracks on long-span cable-stayed bridges can be improved by using unit-plate ballastless tracks with elastic isolation layers.