Modelling of unbound base layer aggregate shape and structure by discrete numerical methods

Abstract

From the point of view of road network infrastructure, the load-bearing capacity of the pavement structure is ensured by general safety, durability, smoothness, noise, economy and other requirements. However, in most cases, these aspects are considered only in the pavement layers of road structures. To date, scientific work has been done to review the upper layers of road construction, i.e. functionality of asphalt or other pavement layers, but little is known about the performance of the base layers. Hence the need to implement an optimal base layer design model. The functionality of unbound base layers, exclusively for the upper base layers, depends not only on the compaction grade and layer thickness, but also on unbound material type, shape, fines content and mechanical properties of aggregates. The response of the pavement structure to loads is expressed through deformations and stresses, which are determined by analytical models. Two typical numerical models are used in the mechanics of materials: continuum and particle interactions. The aim of this research is to define, analyse and systematize the results of scientific research of discrete numerical methods used to model unbound base layers, aggregates based on their shape and structure. Based on the results of the research, conclusions and recommendations for further research of the effect of particle shape and structure on the stiffness modulus of upper unbound base layer are presented.