Monitoring of train-induced responses at asphalt support layer of a high-speed ballasted track

The bituminous underlayment has been introduced to ballasted track systems since the 1970 s in some countries such as Italy, Spain, Japan, and the United States. In China, the interest in this technique arises recently in the construction of high-speed rails (HSRs). It is intended to provide better waterproof and damping performance and thereby to reduce maintenance costs by employing an asphalt layer beneath the ballast. To evaluate the response of the innovative track structure, a monitoring project has been implemented in trial sections of the Beijing–Zhangjiakou HSR in October 2019. Data were acquired at two instrumented substructures during integrated commissioning and testing with the same comprehensive inspection train CRH380AJ-0203 traveling at speeds ranging from 10 km/h to 295 km/h. One section was constructed with fully paved 10 cm thick asphalt concrete (known as asphalt support layer) overlying 60 cm thick graded gravel subgrade, and the other built with a 70 cm thick graded gravel platform supporting the ballast and track components. A total of 14 sensors that include integrated vibration sensors and earth pressure cells were mounted at the subgrade surface right beneath the rails and sleepers. The field measurements include vertical displacements, velocities, accelerations, and stresses under different train speeds, and data treatment and processing techniques are given in detail. Performance comparisons are made between the mechanical response of track substructure in bituminous and standard sections, with emphasis on acceleration measurements. The dynamic amplification factor (DAF) reaches 1.56 and 1.66 in standard and asphalt sections, respectively. The maximum value of extracted peak data points is preferable than the mean value in the performance evaluation of track substructure. Both sections show linear growth of frequency-weighted vertical acceleration levels (VALs) with train speeds; however, significant difference in non-weighted VAL among speeds occurs in the range of 8–20 Hz. The high stiffness and structural integrity of bituminous ballasted track foundations are demonstrated, while the damping and durability performance should be further investigated.

• Record URL:
  https://doi.org/10.1016/j.conbuildmat.2021.123909
• Record URL:
  http://www.sciencedirect.com/science/article/pii/S095006182101669X
• Availability:
  • Find a library where document is available. Order URL: http://worldcat.org/issn/09500618
• Supplemental Notes:
  • © 2021 Elsevier Ltd. All rights reserved. Abstract reprinted with permission of Elsevier.
• Authors:
  • Luo, Qiang
  • Fu, Hang
  • Liu, Kaiwen
  • Wang, Tengfei
  • 0000-0003-4079-0687
  • Feng, Guishuai
• Publication Date: 2021-9-6

Language

• English

Media Info

• Media Type: Web
• Features: Figures; Photos; References; Tables;
• Pagination: 123909
• Serial:
  • Construction and Building Materials
  • Volume: 298
  • Issue Number: 0
  • Publisher: Elsevier
  • ISSN: 0950-0618
  • Serial URL: http://www.sciencedirect.com/science/journal/09500618?sdc=1

Subject/Index Terms

• TRT Terms: Asphalt concrete; Ballast (Railroads); High speed rail; Railroad tracks; Subgrade (Pavements); Train track dynamics
• Geographic Terms: China
• Subject Areas: Materials; Pavements; Railroads;

Filing Info

• Accession Number: 01776891
• Record Type: Publication
• Files: TRIS
• Created Date: Jul 23 2021 3:23PM