Simplified Mechanistic Rut Depth Prediction Procedure for Low-Volume Roads

摘要

A procedure for predicting the number of passes of a wheel load that will cause a specified rut depth was developed, using information which includes the base layer thickness, the resilient moduli and general classification of the granular base course and the subgrade soils. Pavement materials were retrieved from six farm-to-market road sections and permanent deformation tests and resilient modulus tests were carried out. The permanent deformation behavior was modeled as a straight line in a logarithmic plot of the residual strain and the number of load repetitions. Typical slopes and intercepts of this line were determined for various soil materials. Expressions are giving for the intercept as a function of the resilient modulus and the soil classification. The Mechano-lattice approach, which takes into account the realistic interaction effects of the permanent deformation behavior of the individual layers, is shown to produce results which differ from the more commonly used approximate method of superposition.