Development of a test method to identify erosion characteristics

Abstract

Paper presented at the 31st Annual Southern African Transport Conference 9-12 July 2012 "Getting Southern Africa to Work", CSIR International Convention Centre, Pretoria, South Africa.Erosion of the sub-base material in concrete pavements leads to a loss in slab support and thus cracking of the concrete slab itself. This occurrence is indicated when pumping occurs at the joints in the concrete slab and needs to be predicted in the design stage. Current test methods used to evaluate erosion and durability properties, such as the wet and dry durability test takes weeks to conclude and are highly influenced by human factors. This paper describes the design and construction of a Rotational Shear Device (RSD) that can be used to identify erosion characteristics of sub base materials. Results from a series of tests are presented that indicate a potential benefit in the characterisation of erosion properties of sub base materials.