Mechanistic - Empirical Flexible Pavement Analysis Using Load Spectra

  • David O. Awosanya Ahmadu Bello University, Zaria
  • Abdulfatai A. Murana
  • Adekunle T. Olowosulu
Keywords: Multilayer Elastic theory; Layered Elastic Computer program (KENLAYER); Axle load distribution (Axle load spectra).


Prediction of pavement response based on the elasticity theory and multi-load response determined by superimposition of the tire stresses is at the heart of the mechanistic-empirical design procedure. The main focus was that the response of the pavement was modelled in such a way that tensile and compressive strains were predicted based on axle load spectra analysis for an elastic multi-layered system that was subjected to axle load spectra using a layered elastic analysis software program, KENLAYER (in conjunction with the input software LAYERINP and graphic software LGRAPH), which is part of the computer package called KENPAVE. To summarize the tensile and compressive strains results obtained for a Single Axle with Single Tire (SAST) from this study, the critical axle load magnitude for 100 kN is 226x10-6mm/mm and 237.70x10-6mm/mm respectively. For a Single Axle with Dual Tires (SADT), the critical axle load magnitude of 140kN is 243.00x10-6mm/mm and 244.00x10-6mm/mm respectively. For Tandem Axles with Dual Tires (TADT), the critical axle load magnitude of 240kN is 231.00x10-6mm/mm and 231.00x10-6mm/mm respectively.  For Tridem Axle with Dual Tires (TRDT), the critical axle load magnitude of 360kN is 226.60x10-6mm/mm and 229.70x10-6mm/mm respectively. The influence of axle load range is more pronounced for TADT, followed by TRDT. On the other hand, the smallest one is SADT, and SAST is closest to TRDT.


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