We have worked on research projects which have enabled the UK to move away from the historical approach of empirical pavement foundation design towards a performance specification approach that facilitates analytical design. This encourages greater use of secondary and recycled materials and facilitates optimisation of pavement foundation performance.
In order to fully encompass this method a simplified analysis technique was required to establish the resilient modulus and associated permanent deformation of the subgrade materials, as those currently available are confined to research laboratories utilising sophisticated cyclic triaxial testing techniques.
Through a rigorous testing programme a relationship was found between threshold stress and shear strength, alongside confirmation that resilient modulus values can be obtained from a comparative psuedostatic triaxial test method. This research suggests that a simple test method can therefore be used to assist in the mechanistic design of pavement foundations.
Download research paper : Mechanistic Design of Pavement Foundations