Application of Portable Soil Strength Probe on Bengkalis' Peat

Abstract

Peat shear strength measurement in the laboratory is very challenging because undisturbed sampling of very soft peat is very difficult to get. Traditional in-situ test such as standard penetration test (SPT) and cone penetration test (CPT) on peat also have problems i.e. they are very heavy and the measurement is not sensitive on very soft peat. This study described the application of portable soil strength probe on peat. The tool can measure penetration resistance in term of stress and torsion in newton meter. Peat samplings and physical laboratory tests were also conducted. The location of the study is Bengkalis Regency, Riau Province. The result revealed that peat (up to 6-meter depth) at the location is mainly sapric, low ash content with water content more 1000%. Penetration resistance is predominantly 400 kPa. While shear test depicts that peat is mainly frictional with friction angle mainly between 17-21 degrees and very low cohesion i.e. 0.8-3kPa. This study revealed that fibre content correlate moderately with penetration resistance and shear strength. this preliminary work suggested that soil strength probe may be useful for peat characterization.