Study on recyclable precast-slab-fabricated road based on arching effect theory

Abstract

Precast slab parameters are important factors affecting the mechanical performance and service life of precast-slab-fabricated recyclable roads. To clarify the force mechanism of recyclable precast-slab-fabricated roads and provide a basis for selecting slab parameters, a field test of a recyclable road fabricated using a large-scale precast slab was conducted in this study. The horizontal and vertical stresses on the top and bottom surfaces of the precast slab are determined. The stress-time history curves show that the horizontal and vertical stresses have peak values corresponding to the time at which the axle acts directly on the precast slab. Based on the arching effect theory, the mechanical mechanism of a precast-slab-fabricated recyclable road was analyzed. Owing to the arching effect between the precast slabs, they were cooperatively stressed. Compared with precast slab bearing vehicle load independently, When the arch effect works, both the maximum horizontal stress and the vertical stress decrease. According to the field test results, the influence laws of the material, size, thickness, and shape of the precast slab on precast slab stress were obtained. In order to achieve maximum service life and road performance of recyclable Precast-Slab-Fabricated road, the characteristic parameters of the precast slab are suggested as follows. The grade of concrete used for the precast slab should be more than C30, the size of precast slab can be 2 m, large thickness of precast slab should be used(e.g.0.2 m), and square precast slab with width-length ratio of 1 should be adopted as far as possible.