Treatments to improve the aeolian sand foundation in solar park construction

Abstract

The aeolian sand in the Mohammad bin Rashid Al Maktoum (MBR) Solar Park Phase IV Project site in Dubai, United Arab Emirates, is cohesionless, uniformly graded, non-plastic fine sand, with high permeability, low shear strength and low bearing capacity, which are properties that cause many geotechnical and structural challenges. With aeolian sand used as backfill soil, sandstone and sabkha (gatch, gypsum) excavated during field levelling were used as sand fixation material to improve the aeolian sand foundation. In a field compaction test, the compaction method, moisture content, paving thickness, number of rolling passes, backfill layer deformation, compaction coefficient and California bearing ratio were analysed to summarise the technological aspects of the compaction process. Rolling greatly improved the aeolian sand foundation, achieving the required capacity for various projects. The surface layer was stabilised by sandstone–gatch, which had the strongest resistance to wind erosion. By contrast, the resistance of the sandstone–gypsum layer to wind erosion was moderate, and that of the sandstone layer was weak. The experiments used to improve the aeolian foundation in this study can be applied to similar desert areas on the Arabian Peninsula and in North Africa.