JRMGE / Vol 16 / Issue 12

Article

Experimental and numerical modeling on vacuum consolidation behavior of staged-filled soil slurry with prefabricated horizontal drain and flocculant

Ding-Bao Song, Yu Pan, Wen-Bo Chen, Zhen-Yu Yin, Wei-Qiang Feng, Jian-Hua Yin

Show More

a College of Civil and Transportation Engineering, Shenzhen University, Shenzhen, China
b Department of Civil and Environmental Engineering, The Hong Kong Polytechnic University, Hung Hom, Kowloon, Hong Kong, China
c Department of Ocean Science and Engineering, Southern University of Science and Technology, Shenzhen, China


2024, 16(12): 5231-5248. doi:10.1016/j.jrmge.2024.01.026


Received: 2023-09-05 / Revised: 2023-11-20 / Accepted: 2024-01-30 / Available online: 2024-06-13

2024, 16(12): 5231-5248.

doi:10.1016/j.jrmge.2024.01.026


Received: 2023-09-05

Revised: 2023-11-20

Accepted: 2024-01-30

Available online: 2024-06-13


Abstract:

The vacuum-assisted prefabricated horizontal drain offers a promising method for strengthening soil slurry, allowing simultaneous filling and vacuum-dewatering via staged construction. However, there is limited research on the unique characteristics of staged filling. This study aims to investigate the vacuum consolidation process of staged-filled soil slurry through laboratory model tests and numerical simulations, also assessing the impact of anionic polyacrylamide. Comparative analyses are conducted between vacuum consolidation with and without anionic polyacrylamide, as well as self-weight consolidation without anionic polyacrylamide. Results reveal contour lines of excess pore pressure, water content, and soil strength forming an ellipse around the prefabricated horizontal drain board. During the consolidation process, a higher degree of consolidation, lower water content, and higher soil strength were observed closer to the prefabricated horizontal drain board. After treatment, the uppermost filling layer exhibits an average water content that was approximately 40% higher than the lower filling layer, and its average strength was about 60% lower. This discrepancy is primarily due to the absence of sealing on the top surface and the relatively short vacuum consolidation time caused by staged filling. The introduction of anionic polyacrylamide-induced flocculation significantly improves the initial consolidation rate but minimally affects the dewatering capacity of vacuum preloading. Using flocculant can enhance both the staged filling rate and soil strength (by 1–2 times). Additionally, employing a staggered arrangement between different prefabricated horizontal drain layers is advisable to prevent top-down penetration in areas with low soil strength.

Download PDF:


Keywords: Flocculation, Model test, Numerical modeling, Prefabricated horizontal drains, Staged-filled slurry, Vacuum consolidation

Show Figure(s)


Supplementary Material

Download Document:


Share and Cite

Ding-Bao Song, Yu Pan, Wen-Bo Chen, Zhen-Yu Yin, Wei-Qiang Feng, Jian-Hua Yin, 2024. Experimental and numerical modeling on vacuum consolidation behavior of staged-filled soil slurry with prefabricated horizontal drain and flocculant. J. Rock Mech. Geotech. Eng. 16 (12), 5231-5248.

Author(s) Information

Ding-Bao Song

Dr. Ding-Bao Song received his PhD from Huazhong University of Science and Technology in China. He received his BEng and MEng degrees from Shandong University of Science and Technology and China University of Geosciences, respectively. He has more than 10 years of experience in geotechnical engineering, especially in terms of soil consolidation analysis, soft soil treatment, contaminated soil treatment, and interaction between soil and underground structures, etc. His research focus includes experimental and numerical investigations on the treatment of high-water content dredged materials and their beneficial reuse, and coupled consolidation and contaminant transport. He has published 38 journal papers, obtained 5 authorized national invention patents, and 10 authorized software copyrights.