Title: A Study On The Effect Of Calcium Chloride As A Dust Suppresant On The Engineering Properties Of Gravel On Unpaved Roads
Authors: Serunkuuma ibra
Volume: 6
Issue: 9
Pages: 51-62
Publication Date: 2022/09/28
Abstract:
The quality of the gravel used on roads will greatly influence the service life of the road. Addition of calcium chloride as a dust suppressant to the gravel can affect the quality of the gravel. This study was performed to evaluate the effect of calcium chloride on the engineering properties of gravel. Grading, Atterberg limits, maximum dry density, optimum moisture content and California Bearing Ratio values characteristics were determined for the natural gravel and the gravel - calcium chloride mixtures with varying quantities of calcium chloride. Calcium chloride was mixed with gravel in the percentages 2, 3 and 4 by weight of dry soil. The particle size distribution and Atterberg limits did not change significantly. The OMC and MDD reduced and increased respectively on addition of calcium chloride. The OMC reduced from 9.2% to 7.6%, 7.4%, and 7.2% and the MDD increased from 2.15Mg/m3 to 2.31 Mg/m3, 2.34 Mg/m3 and 2.35 Mg/m3 for the respective mix ratios of calcium chloride. The CBR at 95% compaction increased from 25% to 29%, 32% and 36% for the respective mix ratios of calcium chloride. The increase in the dry density is attributed to the increased bonding of the particles and reduction in the air voids due to the hygroscopic nature of the calcium chloride. The increase in dry density facilitates an increase in the CBR due to a change in the soil structure from dispersed to flocculate. This means that calcium chloride can be used in chemical stabilization of gravel wearing course for unpaved roads.