In light of the issues of slow strength enhancement and complex construction associated with traditional expansive soil improvement methods, high-water grouting materials were chosen to improve expansive soil, and then its engineering characteristics under different amendment dosages and different curing ages were investigated. To this end, a series of studies, including slurry compressive and bending tests, unconfined compressive tests, and triaxial tests, were conducted. Experimental results indicate that the use of high-water grouting materials to improve expansive soil can significantly enhance the early strength of expansive soil and reduce its expansibility. As the content of grouting materials increases, the compressive and flexural strength of the modified expansive soil is significantly improved. As the curing age increases, the expansibility of the improved soil gradually decreases, and the strength continues to increase, basically reaching the optimal value at 7 days of curing and tending to stabilize after 7days of curing, demonstrating good early-strength characteristics. The stress-strain curve of the improved soil exhibits a strain-hardening type, and the shear strength increases significantly with the increase in confining pressure. The research results provide a certain reference value for enhancing the engineering application of expansive soil.

Zhenqi Li, Jianfu Zhou, Yuguo Zhang, Jinshuai Kou, Zhenqi Cai, Huijie Zhang. Experimental study on the engineering characteristics of improved expansive soil with high-water grouting materials. Academic Journal of Architecture and Geotechnical Engineering (2026), Vol. 8, Issue 1: 74-79. https://doi.org/10.25236/AJAGE.2026.080109.

[1] Sun De'an, Zhang Junran, Lu Haibo, et al. Soil-water characteristic curve of Nanyang expansive soil in full suction range[J]. Rock and Soil Mechanics, 2013, 34(07): 1839-1846. DOI:10.16285/j.rsm.2013.07.005.

[2] Wang Chenghan, Cha Wenhua, Wang Jingjiu. Review of expansion and contraction mechanism and new treatment methods of expansive soil[J]. Subgrade Engineering, 2020, (02): 6-11. DOI:10.13379/j.issn.1003-8825.2020.02.02.

[3] You Bo, Xu Hongzhong, Dong Jinmei, et al. Triaxial experimental study of basalt fiber reinforced expansive soil[J]. Journal of Disaster Prevention and Mitigation Engineering, 2015, 35(04): 503-507+514.

[4] Wang Huan, Cao Yikang, Ren Junxi, et al. Effect of dry-wet cycle on cracks and strength of improved expansive soil in silt soil[J]. Journal of Building Science and Engineering, 2022, 39(05): 213-221.

[5] LI Jia-ming, TANG Shi-bin, SONG Huai-bo, et al. Engineering properties and microstructure of expansive soil treated with nanographite powder[J]. Journal of Central South University, 2022, 29(02): 499-514.

[6] Fu Ce Ling, Zeng Zhaotian, Mo Hongyan, et al. Experimental study on engineering characteristics of lime modified expansive soil[J]. Journal of Guangxi University (Natural Science Edition), 2019, 44(02): 524-533.

[7] Suo Wentao, Li Xinming, Sun Yuzhou. Strength characteristics and microscopic mechanism of lime-modified Nanyang expansive soil[J]. Subgrade Engineering, 2018, (05): 30-34+64.

[8] Lu Y, Liu S, Zhang Y, et al. Freeze-thaw performance of a cement-treated expansive soil[J]. Cold Regions Science and Technology, 2020, 170: 102926.

[9] Du Jing, Zhou Dong. Experimental study on microbial modified expansive soil[J]. Water Conservancy and Hydropower Technology, 2012, 43(07): 103-105+87.

[10] Ouyang Q, Xiao H, Li Z, et al. Experimental study on the influence of microbial content on engineering characteristics of improved expansive soil[J]. Frontiers in Earth Science, 2022, 10: 863357.

[11] Li Yun-fat, Wang Guiyao, Zhang Yongjie, et al. Experimental study on the effect of planting vetiver roots on expansive soil characteristics[J]. Highway Traffic Science and Technology, 2020, 37(05): 43-52.

[12] Li Zhengyin, Zhang Bin, Zhao Wei, et al. Experimental Study on the Engineering Properties of Cement-Modified Expansive Soil [J]. Comprehensive utilization of fly ash, 2025, 39(05): 97-102.

[13] ZHANG Yuguo, ZHAO Chunhao, ZHANG Zhaobin, et al. Research on the strength characteristics and microscopic mechanism of improved expansive soil with lime-zeolite powder[J]. Silicate Bulletin, 2024, 43(11): 4167-4176.

[14] Chai Shiyu, Zhang Lingkai. Comparative analysis of the influence of different improvement methods on the mechanical properties and physical mechanism of expansive soil[J]. Hydropower and Energy Science, 2023, 41(4): 190-194.

[15] Technical Specifications for Buildings in Expansive Soil Areas: GB50112-2013[S]. Beijing: China Building Industry Press, 2013.