Centrifuge modelling of traffic simulation on a construction waste layer

This paper describes a set of physical modelling laboratory tests on recycled construction and demolition waste (RCDW) in Paraná, Brazil. The physical modelling tests were conducted in the geotechnical beam centrifuge at the Federal University of Rio de Janeiro. The main idea of the tests was to run a wheel cyclically forward and backward on a strip over the RCDW layer applying a constant force corresponding to approximately 1 and 2 t in prototype scale. The force was kept constant through a specially designed control system that moves the actuator up and down in order to compensate for force variations due to horizontal movements. A total cell placed at the bottom of the RCDW layer, just above the middle of the track where the wheel runs, measured the increase in vertical stress. Comparison with a simplified analytical solution results in a slight underestimation of the total stress in the RCDW layer, whereas comparison with a classical elastic solution results in overestimation of the total stress. The permanent wheel track deformation due to the applied load was also measured during the cycles. The deformations observed in the centrifuge tests were higher than those obtained in the cyclic triaxial test.