Utilizing Calcium Carbide Residue and Coconut Shell Ash as Admixture for Tropical Black Clay Stabilization
Abstract:
This study focuses on a Tropical Black Clay (TBC) sourced from Gwako village in Abuja, Nigeria, extracted through disturbed sampling at depths ranging from 0.5m to 1.5m. The TBC was subjected to varying proportions (0%, 2%, 4%, 6%, 8%, and 10%) of Calcium Carbide Residue (CCR) and Coconut Shell Ash (CSA) as additives. The investigation assessed the impact of these additives on key soil characteristics, including Maximum Dry Density (MDD), Optimum Moisture Content (OMC), and Unconfined Compressive Strength (UCS) over curing periods of 1, 7, 14, 28, 60, and 90 days.
The initial analysis of the soil’s index properties revealed its classification as CH and A-7-5 under the Unified Soil Classification System (USCS) and American Association of State Highway and Transportation Officials (AASHTO), respectively. With increasing additive dosages, the MDD of the treated soil exhibited a consistent decrease, ranging from 1.784 g/cm³ at 0% CSA and 0% CCR to a minimum of 1.666 g/cm³ at 8% CSA and 4% CCR. Conversely, the OMC increased from 18.0% (0% CSA and 0% CCR) to a peak of 23.7% (4% CSA and 8% CCR).
In terms of UCS, the treated soil’s strength displayed a general uptrend as both additive dosage and curing period increased. The UCS values rose from 19.196 kN/m² (0% CSA and 0% CCR) to a maximum of 1194.972 kN/m² (0% CSA and 10% CCR) following 90 days of curing. Although the achieved Unconfined Compressive Strength fell short of the 1710 kN/m² requirement for base materials, it comfortably met the range of 687-1373 kN/m² specified for sub-base materials within the tested additive compositions. Consequently, the treated soil holds potential as a suitable sub-base material for lightly trafficked roads.
Utilizing Calcium Carbide Residue and Coconut Shell Ash as Admixture for Tropical Black Clay Stabilization, GET MORE, ACTUARIAL SCIENCE PROJECT TOPICS AND MATERIALS
