Volume 34, Issue 4 (July 2011)
Accelerated Laboratory Pavement Model Test on Cemented Base and Clay Subgrade
This paper examines the pavement model test box (PMTB) testing method and its suitability for determining the stiffness modulus, fatigue and permanent deformation properties of a pavement structure constructed with a cementitiously stabilized granular base layer of 250 mm thickness and a clay subgrade layer of 330 mm thickness that are required for the design of a pavement structure involving these materials. A new laboratory PMTB test setup with extensive instrumentations to measure soil deformations and strains is presented in this paper. The suitability of this testing arrangement for determining the stiffness, fatigue and permanent deformation characteristics of a pavement structure was examined by studying the characteristics of a granular base material stabilized with 1.5 % general blend (GB) cement-flyash and a clay subgrade material. The test was continued at a frequency of 3 Hz up to 8 millions load cycles and measured horizontal tensile strain at the bottom of the stabilised base layer was used to determine the fatigue life of the stabilised layer. This study indicates that the deformation and strain measurement setups used for PMTB testing is suitable for undertaking cyclic load PMTB tests to determine the stiffness, fatigue and permanent deformation properties of the materials reliably.