Effect of Compaction Moisture Content on the Resilient Modulus of Unbound Aggregates from Senegal (West Africa)

Makhaly Ba, Meissa Fall, Oustasse Abdoulaye Sall, Fatou Samb

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DOI: 10.4236/gm.2012.21003                

Abstract

This paper presents the results of research conducted to investigate the effect of compaction moisture content on Resil- ient Modulus (Mr) of unbound aggregates. Three different aggregates (GRB, Basalt and Bandia limestone) was collect- ed from different sites within Senegal and then subjected to repeated load triaxial tests. Test results showed that the ef- fect of compaction water content is more significant in the dry side than in the wet side. The compaction water content has less effect on the GRB and the Basalt than on the Bandia limestone. GRB and Basalt are cohesionless materials and allow water to drain even during the compaction procedure. Change in water content increases as the compaction water content increases because of the drainage of the excess water during the compaction and loading procedures. For GRB and Basalt, at Wopt + 1.5%, most of the excess water is drained during the compaction of the sample and continue to be drained during the Resilient Modulus test. For the Bandia limestone, this drainage is less significant due to cohesion, absorption and hydratation.

Keywords

Resilient Modulus; Summary Resilient Modulus; Quartzite; Basalt; Bandia Limestone

Conflicts of Interest

The authors declare no conflicts of interest.

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