Improving the shear resistance of ground technological quarry roads on loosely-bound subgrades

Abstract

The study aims to solve the urgent problem of strengthening the subgrade of roads for heavy-duty vehicles. In the case of a limited road service life, it appears economically unfeasible to provide a strong cement-concrete subgrade. This case requires a solution maximizing the use of both local materials and production wastes, available in the work area. In order to perform calculations of stresses, arising at a great depth in the subgrade of the technological road under the influence of heavy-duty vehicle wheels, it is necessary to use appropriate mathematical models. In the present study, the calculations were carried out using a software application that implements the method of discrete elements. Using this method, stresses in highly inhomogeneous granular media can be calculated using the first[1]principle approach. The design of road structural layers suggests the use of geocontainers, made of used polypropylene big bags at the subgrade, which, due to their large size, have a greater shear resistance when filled with any soil mixture. The durability of the polypropylene fabric in the roadbed can reach several decades. The main task of the study was to calculate the protective layer of alternated crushed stone, clay soil, and polypropylene fabric. The thickness of layers was selected such that the tensile stresses during the passage of vehicles on the surface of a geocontainer remain within the strength limits of the container shell material.