GEOTECHNICAL EVALUATION OF SOFT SOIL IN MADA REGION: A CASE STUDY FROM KAMPUNG TAJAR, KEDAH

Abstract

Soft soils have emerged as a critical constraint in paddy cultivation within the Muda Agricultural Development Authority (MADA) region, affecting over 8,000 hectares and continuing to expand. Despite recognition of their low strength and high compressibility, limited studies have systematically examined their geotechnical parameters in active paddy fields of Malaysia. This study addresses this gap by assessing moisture content (MC), organic content (OC), maximum dry density (MDD), and optimum moisture content (OMC) of soft soils compared to normal paddy soils. Soil samples were collected from Kampung Tajar, Pendang, Kedah, at two depths (0–20 cm and 20–40 cm) and analyzed in accordance with BS 1377 standards. Results showed that soft soils exhibited consistently higher MC and OC but lower MDD than normal soils, leading to weaker compaction behaviour. Elevated OC was positively associated with MC, while MC showed an inverse relationship with MDD, confirming their causal role in reducing soil strength. These findings highlight the limitations of conventional land preparation and mechanization practices in soft soils. The study provides practical insights for farmers, engineers, and policymakers in designing adaptive soil management and stabilization strategies, and mechanization usage to enhance paddy productivity and ensure long-term soil sustainability.