[1] LIU Bo, LIU Zhanlong, CHEN Shuo, PENG Chao, et al. Performances and environmental responses of a foundation pit with composite supporting mode in water-rich soft soil adjacent to the sea [J]. Journal of Southeast University (English Edition), 2026, 42 (3): 366-378. [doi:10.3969/j.issn.1003-7985.2026.03.009]
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Performances and environmental responses of a foundation pit with composite supporting mode in water-rich soft soil adjacent to the sea(
)
临海富水软土地层复合式支护基坑开挖性能及环境响应
)Journal of Southeast University (English Edition)[ISSN:1003-7985/CN:32-1325/N]
- Volumn:
- 42
- Issue:
- 2026 3
- Page:
- 366-378
- Research Field:
- Civil Engineering
- Publishing date:
- 2026-09-06
Info
- Title:
- Performances and environmental responses of a foundation pit with composite supporting mode in water-rich soft soil adjacent to the sea
- 临海富水软土地层复合式支护基坑开挖性能及环境响应
- Author(s):
- LIU Bo1, LIU Zhanlong2, CHEN Shuo2, PENG Chao2, ZHANG Dingwen3
- 1.College of Civil Engineering, Nanjing Forestry University, Nanjing 210037, China
2.CCCC Third Highway Engineering Co., Ltd., Beijing 101300, China
3.School of Transportation, Southeast University, Nanjing 211189, China
- Keywords:
- foundation pit; soft soil; pile-anchor; grading excavation; numerical simulation; tested performance
- PACS:
- TU473
- DOI:
- 10.3969/j.issn.1003-7985.2026.03.009
- Abstract:
- Foundation pits in coastal, water-rich soft soils face risks and challenges such as excessive deformation, severe seepage, and tight construction schedules. Considering the complex geological and hydrological conditions and the need to balance safety and economy, A composite support scheme that combines pile anchors with graded excavation was proposed. Numerical simulations were conducted to predict deformation of the retaining structure and associated environmental responses, thereby preliminarily verifying the feasibility of the proposed scheme. Finally, a real-time monitoring system was installed to record horizontal and vertical displacements of retaining piles, axial forces in anchor cables, ground settlement, and groundwater levels outside the pit. The temporal evolution and spatial distribution of these responses were analyzed and the effectiveness of the adopted design and construction schemes was validated. The results indicate that most deformation and environmental responses occurred during the dewatering-excavation stage. Anchor cables remained in tension, and tensile force correlated strongly with the deflection of retaining piles. Upper-level anchors developed greater tensile forces than lower-level anchors, reflecting the cantilever deformation mode of the retaining piles. After adopting the composite pile-anchor and grading excavation approach, the maximum retaining wall deflection, maximum ground settlement, and maximum groundwater level variation outside the pit were 28.0, 26.36, and 699 mm, respectively, all of which are within allowable safety thresholds.
- 临海富水软土地层某深基坑面临变形大、渗漏严重和施工工期紧等风险和挑战。基于复杂的地质、水文条件,综合考虑安全性和经济性,提出了桩锚联合放坡开挖的复合支护模式;然后,通过数值模拟预测该方案下施工引起的围护结构变形和环境响应,初步验证所提方案的可行性;最后,建立实时监测系统,对施工过程中的围护桩水平和竖向位移、锚索轴力、地表沉降、坑外地下水位进行监测,明确了其时间演化和空间分布特征,验证了所用方案的有效性。结果表明:基坑围护结构变形及环境响应主要发生在基坑降水开挖阶段;锚索呈受拉状态,且拉力与围护桩侧移相关性较强,上层拉力大于下层拉力;采用桩锚联合放坡开挖方案后,围护桩最大侧移为28.0 mm,地表最大沉降为26.36 mm,坑外水位最大变化量为699 mm,均在安全控制值范围内。
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Memo
- Memo:
-
Received: 2025-04-07; Revised: 2026-01-13.
Biography: LIU Bo(1989—), male, doctor, associate professor, boliu@ njfu.edu.cn.
Foundation items: The National Natural Science Foundation of China (No.52208334), the Jiangsu Urban Underground Space Development and Utilization and Safety Protection Engineering Research Center (No.2023-CSDXJJ-02), the Anhui Province Key Laboratory of Building Structure and Underground Engineering (No.KLBSUE-2023-1).
Citation: LIU Bo, LIU Zhanlong, CHEN Shuo, et al. Performances and environmental responses of a foundation pit with composite supporting mode in water-rich soft soil adjacent to the sea[J]. Journal of Southeast University (English Edition), 2026, 42(3): 366-378. DOI: 10. 3969/j. issn. 1003-7985. 2026. 03. 009.