Improving strength and hydraulic characteristics of regional clayey soils using biopolymers

This paper portrays a unique demonstration of sustainable low-cost ground improvement for regional soil deposits, by comparing locally sourced biopolymer soil stabilisation soil with im-ported biopolymer stabilisation. The conventional materials often utilized for soil and ground improvement come with major challenges of large carbon footprints and some negative envi-ronmental impacts. As a result, suitable eco-friendly and sustainable materials are necessary. In this study, the potential use of Rice Husk Powder (RHP), Cassava Peel Powder (CPP) and Car-boxymethyl Cellulose (CMC), as biopolymer-based materials to improve the engineering prop-erties of a regional clay was investigated using a gamut of geotechnical compaction, strength and hydraulic conductivity tests according to BS 1377, 1990. The results revealed that locally sourced CPP performed better than both imported CMC and local RHP in improving the engineering properties of the regional clay. The shear strength value of the natural clayey soil (43.5 kPa) increased twenty and ten times respectively when treated with CPP (893 kPa) and CMC (450 kPa). One percent content of CPP and CMC performed optimally among the (0.5, 1.0, 1.5, 2 and 2.5) percent studied in improving the engineering properties of the case study regional clay.

Automated summary

This study investigated the potential of using locally sourced biopolymer soil stabilisation materials to improve the engineering properties of regional clay soils. The results showed that the use of locally sourced materials significantly enhanced the engineering properties of the clay, with cassava peel powder performing the best.