Application of Bamboo Joint Pile in Strengthening Composite Foundation of Variable Cross-Section Screw Pile
-
摘要: 沿海软土地区某料棚工程采用变截面挤密螺纹桩复合地基，在堆载高度到5～6 m时，未达到设计高度11 m，地面产生沉陷，最大沉陷量约1.30 m，网架立柱出现了较大的变形，最大水平位移超过680 mm，导致料棚处于超危状态。采用竹节桩对挤密螺纹桩复合地基进行加固，通过合理布置竹节桩打桩流向，采用长螺旋引孔、应力释放孔，减小竹节桩沉桩的挤土效应对原有挤密螺纹桩、边柱承台和基桩的影响。沉桩结束后，竹节桩单桩竖向承载力特征值不小于740 kN，满足竹节桩设计要求。加固后的竹节桩复合地基+筏板满足堆载的设计要求。Abstract: The composite foundation with variable cross-section compacted screw pile was conducted in soft soil area. When the stacking height reaching 5～6 m, which was below the design height of 11 m, the ground subsidence occurred and the maximum subsidence was about 1.30 m. The grid frame column had a large deformation, and the maximum horizontal displacement was more than 680 mm, which led to the material shed in an ultra dangerous state. Bamboo joint pile was used to reinforce the composite foundation of variable cross-section compacted screw pile. By reasonably arranging the driving direction of bamboo joint pile, adopting long auger and stress release hole, the influence of soil squeezing effect of bamboo joint pile on original compacted screw pile, side column cap and foundation pile was reduced. After the pile sinking, the characteristic value of the vertical bearing capacity of the single bamboo joint pile was not less than 740 kN, which meet the design requirements. The reinforced bamboo pile composite foundation+ raft meet the design requirements of surcharge.
-
表 1 土层基本物理力学性质指标
土层编号 土层名称 w/% γ/(kN·m−3) $ e $ fa/kPa qpa/kPa ② 软土 42.7 17.3 1.200 60 20 ③ 粉质黏土 34.6 17.9 1.003 80 40 ④ 粉土 24.0 18.0 0.826 100 26 ⑤ 粉质黏土 29.5 18.3 0.890 110 40 ⑥ 粉土 25.4 18.2 0.824 120 30 ⑦ 砂质粉土 22.4 18.6 0.741 170 50 ⑧ 粉质黏土 24.8 18.5 0.799 150 60 ⑨ 粉砂 200 70 ⑩ 粉质黏土 27.7 18.4 0.847 160 70 
下载: 导出CSV
-
[1] 孙文怀,张元冬. 螺纹桩在软弱地层中的应用[J]. 华北水利水电学院学报,2009,3(6):74-76. [2] 窦德功,高 倩. 螺纹桩竖向承载力及其影响因素研究[J]. 港口技术,2019,(6):55-59. [3] 冷伍明,魏广帅,聂如松,等. 螺纹桩竖向承载特性及承载机理研究[J]. 铁道工程学报,2020,260(5):1-6, 35. doi: 10.3969/j.issn.1006-2106.2020.05.001 [4] 钱建固,陈宏伟. 注浆成型螺纹桩接触面特性试验研究[J]. 岩石力学与工程学报,2013,32(9):1744-1750. doi: 10.3969/j.issn.1000-6915.2013.09.003 [5] 周敏明,钱建固,黄茂松,等. 注浆成型螺纹桩桩土接触面机制的离散元模拟[J]. 岩土力学,2016,37(1):591-597. [6] 周 杨,肖世国,徐 骏,等. 变截面螺纹桩竖向承载特性试验研究[J]. 岩土力学,2017,38(3):747-756. [7] HO H M,MALIK A A,KUWANO J,et al. Influence of helix bending deflection on the load transfer mechanism of screw piles in sand: experimental and numerical investigations[J]. Soils and Foundations,2021,61(3):874-885. doi: 10.1016/j.sandf.2021.04.001 [8] SALEEM M K,MALIK AA,KUWANO J,et al. Model study of screw pile installation impact on ground disturbance and vertical bearing behaviour in dense sand[J]. Conference Series: Earth and Environmental Science,2021,710(1):012056 (9pp). [9] 周佳锦,王奎华,龚晓南,等. 静钻根植竹节桩桩端承载性能试验研究[J]. 岩土力学,2016,37(9):2603-2610. [10] 周佳锦,龚晓南,严天龙,等. 软土地区填砂竹节桩抗压承载性能研究[J]. 岩土力学,2018,39(9):3425-3433. [11] 凌 造,吴江斌. 软土地层静钻根植桩承载性状数值模拟分析[J]. 建筑科学,2020,36(S1):94-103. [12] 郦 亮,叶俊能,周 晔,等. 软土地区竹节桩复合地基承载特性试验研究[J]. 地下空间与工程学报,2020,16(4):986-992. [13] 王忠瑾,方鹏飞,谢新宇,等. 带肋竹节桩竖向抗压承载力影响因素分析[J]. 岩土力学,2018,39(S2):381-388. [14] 何福渤. 长螺旋钻孔植桩工法竹节桩承载力试验研究[J]. 建筑科学,2021,37(1):50-56. -
图(8) / 表(1)
计量
- 文章访问数: 72
- HTML全文浏览量: 55
- PDF下载量: 25
- 被引次数: 0
