Test of the influence from mica and LWA on permanent deformations and calculation of the elastic and permanent response under HVS testing

摘要

A major distress problem on roads is rutting. Especially for roads with thin asphalt layers this is a typical problem when permanent deformation occurs in the unbound material under loads from heavy vehicles. Two frequent problems for the SNRA are addressed in this paper. The first is that high mica content in the unbound materials is believed to have a strong negative effect on the plastic deformations. The second problem is that roads with a light weight clay aggregate (LWA) as filling displays frequent problems with rutting. These two problems were addressed at a full-scale test with the Swedish/Finnish HVS during the summer of 2003. The test was conducted in connection with a large motorway project (E6). Four test sections with varying mica content in the unbound base and four sections with light weight clay aggregate (LWA) were constructed for HVS testing. Elastic and permanent response were measured under the HVS as well as extensive laboratory material testing and FWD loading. The project was subject to an international workshop in September 2003 were invited researcher compared response models to the test results. The major findings from this workshop are presented in the paper.