Tropical Residual Soil Stabilization: A Powder Form Material for Increasing Soil Strength
Nima Latifi1; Amin Eisazadeh2; Aminaton Marto3; Christopher L. Meehan4
1Post-Doctoral Researcher, Mississippi State University, Dept. of Civil and Environmental Engineering, Starkville, MS 39762, U.S.A.
E-mail:
nlatifi@cee.msstate.edu (corresponding author)
2Senior Lecturer, Universiti Teknologi Malaysia, Dept. of Geotechnic & Transportation, Faculty of Civil Engineering, 81310 UTM Skudai, Johor, Malaysia.
E-mail:
a.eisazadeh@yahoo.com
3Professor, Universiti Teknologi Malaysia, Dept. of Geotechnic & Transportation, Faculty of Civil Engineering, 81310 UTM Skudai, Johor, Malaysia.
E-mail:
aminaton@utm.my
4Bentley Systems Incorporated Chair of Civil Engineering & Associate Professor, University of Delaware, Dept. of Civil and Environmental Engineering,
301 DuPont Hall, Newark, DE 19716, U.S.A.
E-mail:
cmeehan@udel.edu
Construction and Building Materials, 2017, Volume 147, pp. 827-836
Abstract
Stabilization of problematic soils for earthwork applications can be performed using a variety of chemical
additives, with lime, cement, or fly ash all being traditionally employed for this purpose. More recently,
various new calcium-based additives have been actively marketed by a number of companies for soil stabilization
applications. The stabilizing mechanisms of these commercially available products are not fully
understood, and their proprietary chemical composition makes it difficult to predict their effectiveness.
The current study examines the effectiveness of SH-85, a new calcium-based powder additive which is
prepared from biomass silica, for stabilization of a tropical residual laterite soil. At the macro-level,
changes in soil strength due to additive stabilization were assessed using a series of unconfined compression
strength (UCS) tests. The underlying mechanisms that contributed to the stabilization process were
explored using spectroscopic and microscopic techniques, including X-ray diffractometry (XRD), energy-dispersive
X-ray spectrometry (EDAX), field emission scanning electron microscopy (FESEM), and Fourier
transform infrared spectroscopy (FTIR). The UCS test results indicated that the addition of SH-85 powder
had a significant stabilizing effect on the laterite soil, with the UCS values increasing fivefold after a 7-day
curing period. At the micro-level, addition of SH-85 had a weathering effect on the clay minerals, changing
the peak intensities of the observed minerals in the XRD spectrums as the stabilized soil was cured. A
significant change in the soil fabric was also observed with curing time in the FESEM tests, with additive
stabilization yielding a less porous and denser soil fabric, and changes in the surface appearance of treated clay particles. This research study confirms the potential of SH-85 as an alternative to traditional stabilizers
for construction involving tropical residual soils.
Keywords
Laterite soil;
Non-traditional additive;
Unconfined compression strength (UCS);
X-ray diffractometry (XRD);
Energy-dispersive X-ray spectrometry
(EDAX);
Field emission scanning electron
microscopy (FESEM);
Fourier transform infrared spectroscopy
(FTIR)
Reference
Latifi, N., Eisazadeh, A., Marto, A., and Meehan, C. L. (2017). “Tropical Residual Soil Stabilization: A Powder Form Material for Increasing Soil Strength.” Construction and Building Materials, Elsevier, 147, 827-836. (doi:10.1016/j.conbuildmat.2017.04.115)
