Experimental Assessment of Coal-based Solid Waste Improved Loess Model Test under Freeze–thaw Action

• Main Authors: WU Libo, LIU Huiyang, LIN Zhanju, YANG Jiawei, CHEN Hongxin
• Format: Article in Journal/Newspaper
• Language: English; Chinese
• Published: Editorial Department of Journal of Sichuan University (Engineering Science Edition) 2025
• Subjects: freeze - thaw action; coal gasification slag; coal gangue; loess; subgrade model; hydrothermal distribution; deformation; Engineering (General). Civil engineering (General); TA1-2040; Hydraulic engineering; TC1-978; permafrost
• Online Access: https://doaj.org/article/10301913c25e4b8085d18d082d18ee2f

ObjectiveThe influence of cyclic freeze-thaw cycles has been identified as a primary factor contributing to the susceptibility of subgrades in loess areas of Northwest China to freeze-thaw diseases. Additionally, frost heave and thaw subsidence have been recognised as significant engineering challenges in road construction in cold regions. The quality of the soil constituting the subgrade is a pivotal factor in determining its vulnerability to freeze-thaw disease. However, the current civil engineering industry in cold regions and road projects are confronted with a scarcity of sand and gravel and other raw materials. Consequently, in loess areas, improved loess as a filler is frequently the preferred material for road construction. However, the utilisation of cement, lime and other inorganic binding materials to enhance loess can result in environmental degradation, while the employment of microorganisms and other novel materials to improve loess is more costly. Consequently, the present study aims to address the pressing issues of coal gangue, coal gasification coarse slag resourceful use and ecological environmental protection in Ningxia and other regions, by exploring the potential of combined utilisation of these novel materials. The study focuses on the utilisation of coal gangue and coal gasification coarse slag in the enhancement of loess subgrades, particularly in the context of freezing and thawing, moisture changes, displacement, and the underlying mechanisms that facilitate these processes. The objective is to mitigate the freezing and thawing disease afflicting the seasonal permafrost area loess subgrades, thereby broadening the scope of the utilisation of coal-based solid waste and offering a novel approach as a reference.MethodsThe research findings on the mechanical properties of gangue and coal gasification coarse slag-improved loess, along with the pre-test results and extant research results, were taken into consideration. The study determined three coal-based solid waste improved loess ...