Strength and Road Performance of Superabsorbent Polymer Combined with Cement for Reinforcement of Excavated Soil

The process of road construction is often accompanied by a large number of excavation work, and most of the excavated soil has poor engineering performance and needs to be transported away. It has the significance of environmental protection and cost saving to treat the excavated soil as pavement materials. The aim of this study is to present laboratory experiments into the mechanical properties, engineering properties, and microstructure of excavated soil stabilized by ordinary Portland cement (OPC) and superabsorbent polymer (SAP). Laboratory experiments were performed to determine unconfined compressive strength (UCS), compactness, durability after wetting and drying cycles, drying shrinkage, and California bearing ratio (CBR). Apart from these, X-ray diffraction (XRD) and scanning electron microscopy (SEM) were used for the microstructure analysis to understand the impact of SAP on cemented excavated soil. It shows that SAP can effectively improve the strength and the compaction of cemented excavated soil with good durability. Although SAP will reduce the CBR value of cemented excavated soil, it still meets the requirements of engineering acceptance. Microscopic analysis shows that SAP absorbs water in the cemented excavated soil and plays a filling role.