Application of Fluidised Solidified Soil in Backfilling Narrow Foundation Pits and Trench Excavations

DOI: https://doi.org/10.62517/jcte.202606103

Author(s)

Huawei Qi, Fuqiang Wang

Affiliation(s)

Anhui Jiaokong Construction Engineering Group Co., Ltd., Hefei, China

Abstract

Addressing the challenges of backfilling deep, narrow trenches around new basement structures in urban renewal projects—where complex road layouts and environments, proximity to residential areas and municipal parks, and difficulties in ensuring adequate compaction with traditional backfill materials are prevalent—this paper systematically investigates the application of fluidised solidified soil in confined space backfilling. Taking the North Garden Renovation Project of Hefei DXL Hotel as a case study, the research focuses on: Through mix design and testing, a material ratio meeting strength and flowability requirements was established. A layered pumping construction technique and comprehensive quality control measures were proposed. Field practice demonstrated that fluidised solidified soil exhibits excellent self-compaction and workability, adapting to confined working environments less than 0.5m wide. Backfill compaction exceeded 98%, effectively mitigating settlement and leakage risks. Compared to conventional lime-soil backfilling, this technology reduces construction duration by approximately two-thirds and lowers overall costs by 18.2%. It minimises environmental impact while offering advantages in environmental protection, noise reduction, and safety, providing a reliable, efficient, and green solution for similar confined space backfilling projects.

Keywords

Fluidised Stabilised Soil; Confined Spaces; Manure Pit Backfilling; Pumped Construction

References

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