Shrinkage behaviour of crushed basaltic rock and residual clay mixture stabilized with cementitious binders

This laboratory investigation was focussed on shrinkage behaviour of stabilized crushed basaltic rock with varying quantities of fine-grained soil and cementitious binders drying under different conditions. The study is applicable to in-situ stabilization of degraded road pavements or construction of new pavements where the available material may have significant quantities of reactive fines. One conventional cementitious binder and two binders comprising industrial waste products were used as cementitious additives. Locally available basaltic crushed rocks and highly plastic basaltic clay were used as the host pavement material and the fine-grained soil, respectively. Shrinkage tests were carried out under two drying conditions, namely one- and three-dimensional drying. It was observed that inclusion of fine-grained soil had significant adverse effect on the shrinkage characteristics of stabilized pavement materials, particularly increasing the potential for cracking. One-dimensional drying featured slower rate of shrinkage development but higher final shrinkage in comparison to three-dimensional drying. This was validated by carrying out similar tests on clay soil only. Effects of different types and quantities of binders on shrinkage performance are presented in this paper.