Laboratory vibration testing and analysis of hot mix asphalt mixture under different loading patterns

Analyzing asphalt mixtures' dynamic behavior under loading conditions is a highly effective way to predict pavement service life and minimize failures. The most effective method to understand a structure's dynamic behavior in mechanics is to propagate waves and vibrations and observe their structural response. The present study uses a vibration system to simulate stress from multiple-axle configurations on asphalt pavement by propagating three haversine waves. The speed and mixture design are the two main variables in this research. The mixture designs used in this study are divided into two categories: dense and open-graded. In each category, parameters such as penetration grade, percentage of asphalt, effective asphalt content, particle size effects, and Marshall Parameters have been investigated. Additionally, this experiment examines the dynamic response of the asphalt sample in the form of two dependent variables: the maximum recorded acceleration in each pulse and the ratio between these accelerations in tension and compression. The results indicate that the phenomenon of wave interference has either constructive or destructive effects at certain speeds. This phenomenon may increase the impact of a tridem axle load compared to a tandem axle load, assuming their total weight remains constant. The rate of acceleration during tridem axle passage is higher compared to tandem axle passage. Wave interference has been primarily influenced by vehicle’s speed and air void percentage in asphalt mixture. The study indicated that critical speeds of 60 and 100 Km/h had the greatest amplification coefficients of 1.88. The air void percentage is a crucial design factor that directly affects wave interference. In simpler terms, a dense mixture design reduces the amplification of multi-axial stress. More importantly, the bitumen penetration grade and effective bitumen percentage in the mixture had a major effect on stress absorption and maximum acceleration reduction.

Language

  • English

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Filing Info

  • Accession Number: 01912084
  • Record Type: Publication
  • Files: TRIS
  • Created Date: Mar 18 2024 5:19PM