Temperature features of the asphalt concrete waterproofing layer on high-speed railway in cold regions. (25th October 2021)

• Record Type: Journal Article
• Authors: Xu, Gang; Zhou, Jie; Chen, Xianhua; Liang, Yilong; Cai, Degou; Lou, Liangwei
• Is Part Of: Construction & building materials. Volume 305(2021)
• Publication Date: 2021-10-25
• Subjects: Asphalt concrete -- High-speed Railway -- Geotextile -- Temperature field -- Temperature gradient -- Tensile strain; Building materials -- Periodicals; 624.18
• DOI: 10.1016/j.conbuildmat.2021.124665
• Languages: English
• ISSNs: 0950-0618

Abstract

Highlights: The field test results indicated that the longitudinal strain on the asphalt concrete waterproofing layer surface changed periodically. The geotextile could effectively reduce the peak tensile strain on the asphalt concrete waterproofing layer surface. The recommended one-sided length of geotextile is suggested as 1 m − 2 m. Abstract: The asphalt concrete waterproofing layer (ACWL) has been used as a potential waterproofing structure for the subgrade in Chinese high-speed railway in cold regions. The waterproofing behavior and dynamic response of ACWL have been evaluated in the previously published studies. However, the research on the temperature and thermal stress distribution in ACWL track structure has not yet been studied. This research aims at investigating the strain distribution of ACWL under the temperature influence in winter. The field test was conducted to monitor the strain changes on the ACWL surface under ambient temperature. A 3D numerical model of track structure with ACWL was also developed based on the thermo-mechanical coupled method. The field test results indicated that the longitudinal strain on the ACWL surface changed periodically with the air temperature while the tensile strain increased with the decrease in temperature. The temperature analysis showed that the temperature change inside the track structure caused by the daily temperature change was mainly focused on the depth range from the track slab to the base plate. The maximum negative temperature gradient inside the track slab was reported to occur at 4:00 a.m in winter. The geotextile was further introduced to weaken the bond between the base plate and the ACWL. The calculations proved that the geotextile could effectively reduce the peak tensile strain on the ACWL surface at the joints of the base plates. 1 m − 2 m geotextile was recommended to be placed at both sides of the joint of the base plates.