Partial replacement of normal sand with garnet waste for bedding sand layer of concrete block pavement

Abstract

Highway construction use river sand as a part of the materials. Due to fast developments, normal sand demand is increase and over exploited in construction. The increase in rate leads to increase in demand for raw materials which in turn leads to price hike of raw materials. Therefore this research aims to investigate the suitability of garnet waste to replace sand partially or fully as bedding materials. The objectives of the research are to determine the California Bearing Ratio (CBR) value at various content of sand-garnet ratio to be applied as bedding sand layer of concrete block pavement (CBP). Samples are labelled as 10S, 9S1G, 8S2G, 7S3G, 6S4G and 10G to differentiate the garnet waste content. Sieve analysis was carried out accordance to BS 882. Optimum moisture content (OMC) of sample was determined using compaction proctor test that refers to BS1377-2. Then the OMC used to determine CBR value of samples that accordance to BS1377-4. Experimental sieve analysis, OMC at maximum dry density (MDD) and CBR value were analysed and compared to the requirements to be applied as bedding sand layer. CBR value of sample type 10S, 9S1G, 8S2G, 7S3G, 6S4G and 10G were calculated 24.85%, 38.92%, 41.26%, 49.5% 47.83% and 42.67% respectively. Sample type 7S3G showed the highest CBR value of samples. However, only sample type 9S1G and 8S2G meet the requirements as materials for bedding sand layer application. Even all samples achieve acceptable CBR value for fine grained soil, but only sample type 9S1G and 8S2G meet the requirements of BS882 grading curve for bedding sand layer materials. Therefore, this research proposes the usage of 20% garnet waste for bedding sand layer application.