Effect of Melon Husk and Cocoa Pod Ashes on Compaction and Strength Characteristics of Lateritic soil

Abstract

Stabilization of weak lateritic soils using melon husk and cocoa pod
ash (MHA and CPA) was studied and reported in this paper. The
MHA was considered as a Class C group of the ASTM (American
Society for Testing and Materials) pozzolan. The soils used in the
study were obtained from depth of exhausted good quality materials
of borrow pits at Auchi Polytechnic, Area II, Auchi South-south
Nigeria. The materials were analyzed for main geotechnical index
properties, compaction and strength (CBR) characteristics. The
MHA and CPA pozzolan stabilizer was administered to the soil
samples up to 12% and at a rate of 2%. The experimental results
comparing the strength of the natural soil samples with the MHA-
CPA-stabilized samples revealed that MHA-CPA increases the
California Bearing Ratio (CBR). AASHTO (American Association
of State Highway and Transportation Officials) classified A-5 and
A-5 subgrade soils. An optimum stabilizer content of 8% was
determined with about 50% advantages in the CBR (increase in
CBR of stabilized soil / CBR of raw soil × 100) for unsoaked
conditions. At the established optimum stabilizer content, the weak
hitherto unsuitable soils have been improved to meet the
requirements for Type 2 subbase road development soils.