Open Access

ARTICLE

Improved Geotechnical Behavior of an Expansive Soil Amended with Cationic Polyacrylamide

by Shengquan Zhou¹, Minjie Shi^1,*, Wei Chen¹, Yongfei Zhang¹, Weijian Wang¹, Haojin Zhang¹, Dongwei Li²

1 School of Civil Engineering and Architecture, Anhui University of Science and Technology, Huainan, 232001, China
2 School of Civil and Architectural Engineering, East China University of Technology, Nanchang, 330013, China

* Corresponding Author: Minjie Shi. Email:

Journal of Renewable Materials 2021, 9(11), 1941-1957. https://doi.org/10.32604/jrm.2021.015693

Received 06 January 2021; Accepted 01 April 2021; Issue published 04 June 2021

Abstract

The characteristics of soil treated with cationic polyacrylamide (CPAM) mass content of 0%, 0.2%, 0.4%, 0.6%, 0.8%, and 1% were investigated through a series of laboratory tests to explore the practical engineering effect of an expansive soil amended with environmental protection material CPAM. The results indicate that with the increasing CPAM content, the liquid limit and plasticity index of soil decrease, the plastic limit increases, and the free swelling ratio and loaded swelling ratio decrease. Besides, the improved soil has less disintegrating property and better water stability. The shear strength increases as the content increases, and the optimal content is 0.6%. Meanwhile, the cohesion of the soil first increases and then decreases, and the internal friction angle increases. Additionally, the unconfined compressive strength first increases and then decreases. The improved soil presents the characteristics of brittle failure and reaches the peak value (410.1 kPa) at the content of 0.8% after curing for 14 days. Scanning electron microscope (SEM) exhibits that the number of curved and wrinkled sections of the expansive soil is reduced after CPAM improvement. Simultaneously, the arrangement of the superimposed polymer changes from face-face to side-angle or side-face-angle, and the reticular structure formed improves the strength and spatial stability of the soil. Therefore, adding appropriate cationic polyacrylamide could improve expansive soil in engineering.

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