Characterization of expansive soils treated with lignosulfonate

Abstract

The current study examines the potential of lignosulfonate to enhance the engineering behavior of two locally available expansive soils. The expansive soils were collected from Vijayawada and Amaravathi, located in the Capital Region of Andhra Pradesh, India. The soils were treated with four different percentages (0.5, 1, 2, and 4) of lignosulfonate and were allowed to interact for 7 and 28 days. A series of laboratory tests such as unconfined compressive strength, cation exchange capacity and scanning electron microscopy were carried out on the soil specimens. The results indicated that lignosulfonate has significant influence on the strength behavior of expansive soils. The amount of fines content present in soils defines the optimum percentage of lignosulfonate. Lignosulfonate treatment resulted in reduced negative surface charge of soils and formation of Polymer chain microstructure along with flocculated or aggregated particle microstructure, which may attribute to the enhanced strength of the expansive soils.

An Eco-Sustainable Stabilization of Clayey Road Subgrades by Lignin Treatment: An Overview and a Comparative Experimental Investigation

“…Similar results were reported by Chavali and Reshmarani [67] in their study on an expansive clayey soil treated by lignosulfonates. SEM images showed the formation of polymeric chains in the microstructure of the lignosulfonate soil.…”

Field Test on Soybean-Urease Induced Calcite Precipitation (SICP) for Desert Sand Stabilization against the Wind-Induced Erosion

“…In such conditions, a chemical solidification approach is employed [6,7]. In the chemical modification method, different organic and inorganic materials, namely cements, products of petroleum, and synthetic polymers as stabilizers, are employed [8][9][10][11]. These stabilizers avoid wind-induced soil erosion by immobilizing sandy soils.…”

Experimental Study on Expansive Soil Improved by Lignin and Its Derivatives

“…In the direct shear test, the stress condition is set to low everyday stress, achieved by the sandbag equivalent substitution method. The downward vertical normal pressure is set to 15,25,35, and 50kPa, a total of 4 levels. The test instrument is a ZJ type of strain-controlled direct shear apparatus produced by Nanjing Soil Instrument Factory, and the hand wheel speed is 4r/min.…”

“…The results showed that the negative charge on the surface of the improved soil was reduced, and the microstructure of the polymer chain was formed. The amount of modifier was related to the particle size of the soil [15]. Wang et al used lignin to improve expansive soil.…”