This paper describes the evaluation of five unbound granular basecourse materials for use in permeable pavements. The materials tested comprised a DGB20 crushed rock and four materials derived from the crushed rock by progressive scalping out of the fines and by reducing the maximum particle size to 13 mm. The materials were evaluated in terms of their permeabilities and their mechanical properties in repeated triaxial loading tests. The mechanical properties could be conveniently represented by the resilient modulus and a simple model of high predictive value was formulated to relate the modulus to the applied stresses. It was found that the coefficient of uniformity represented a simple means of characterising the materials that could be related to both the permeability and the resilient modulus. The paper shows that the choice of permeable base represents a compromise between high permeability and low structural stiffness. (a)
Samenvatting