Research on Construction Technology and Stress of Retaining Structure System with Recoverable Soil Nail Wall
-
摘要: 基于绿色环保与碳中和理念，提出一种可回收的土钉墙支护结构体系，对该体系构件及施工工艺流程进行了介绍，依托实际工程，探讨了1∶0.30、1∶0.50、1∶0.70支护坡比下土钉轴力、主动土压力的变化规律，分析了不同支护坡比对土钉轴力、主动土压力的影响，与规范中的修正公式计算出的理论值进行对比。研究表明，同一深度的主动土压力和土钉轴力随坡比增加而增加，同一坡比下的主动土压力和土钉轴力随深度增加而增加；主动土压力的实测值与计算值随深度变化呈现相同趋势，计算值略大于实测值，土钉轴力的实测值与计算值随深度变化亦呈现相同趋势，但计算值远大于实测值。Abstract: Based on the concept of green environmental protection and carbon neutrality, a recyclable soil nail wall supporting structure system was proposed, and the composition and construction process of the supporting structure system were introduced. The new supporting structure system was applied to practical engineering, and its mechanical performance was discussed. The variation laws of soil nailing axial force and active earth pressure under 1∶0.30, 1∶0.50 and 1∶0.70 supporting slopes were discussed, and the influences of different supporting slopes on soil nailing axial force and active earth pressure were analyzed, which were compared with the theoretical values calculated by modified formula in the code. The test results show that the axial force of soil nailing and active earth pressure increase with the increase of slope in the same depth. For the earth pressure at the same slope, the axial force of soil nailing increases with the increase of depth. According to the change of depth, comparing the actual value with the theoretical value, it can be concluded that the theoretical value and the actual value of active earth pressure have the same trend with the change of depth, and the theoretical value is slightly larger than the actual value. The theoretical value and actual value of axial tensile force of soil nailing show the same trend with the increase of depth. There is a big difference between the calculated axial force and the actual monitored axial force, and the theoretical calculation is relatively conservative.
-
表 1 剖面土层参数
序号 土类名称 土层厚度/m 密度/(g·cm−3) c/kPa $ \varphi $/(°) 1 杂填土 4.20 1.80 10.00 18.00 2 粉砂 2.00 2.00 0.00 28.00 3 砂质粉土 1.60 1.98 10.00 28.50 4 粉质黏土 2.20 2.06 24.50 20.60 5 黏质粉土 4.20 2.04 24.00 19.40 6 粉质黏土 4.00 2.04 26.00 21.55 7 粉砂 1.50 2.00 0.00 28.00 8 黏土 2.80 1.83 50.50 12.50 9 细砂 7.20 2.05 0.00 32.00 10 卵石 2.15 0.00 36.00 
下载: 导出CSV
表 2 郎肯主动土压力值
深度/m φ/(°) Ka,i σak/kPa ci/kPa Pa,k/kPa 5 28 0.361 91.6 0 33.068 6.4 28.5 0.354 133.68 10 35.424 7.8 28.5 0.354 147.28 10 40.237 9.2 20.6 0.479 176.12 20.6 55.851
下载: 导出CSV
表 3 不同坡比下主动土压力折减系数
$ \zeta $ (坡比1∶0.30) $ \zeta $ (坡比1∶0.50) $ \zeta $ (坡比1∶0.70) 0.642 0.481 0.359
下载: 导出CSV
表 4 修正后的主动土压力
深度/m $p{'_{\rm{a}}}$/kPa 坡比1∶0.30 坡比1∶0.50 坡比1∶0.70 5 21.23 15.906 11.871 6.5 22.531 17.039 12.717 7.8 25.832 19.354 14.445 9.2 35.856 26.864 20.051
下载: 导出CSV
表 5 土钉轴向拉力标准值
深度/m ${N_{{\rm{k}},j} }$/kN 坡比1∶0.30 坡比1∶0.50 坡比1∶0.70 5 54.166 40.582 30.289 6.5 51.547 38.370 28.384 7.8 53.465 40.057 29.897 9.2 65.575 49.130 36.669
下载: 导出CSV
-
[1] 何江飞. 土钉墙支护结构的作用机理及面层受力分析研究[D]. 兰州: 兰州理工大学, 2010. [2] 柳颂丹. 绿色土钉墙支护结构体系施工工艺及经济性分析[D]. 北京: 北京建筑大学, 2020. [3] SEED H B,REESE L C. The action of soft clay along fraction piles[J]. ASCE Translation,1957,122:92-101. [4] 张建龙,何家柱. 基坑土钉支护结构受力及变形分析[J]. 工程勘察,2003,(2):39-41. [5] 胡 渊,张福龙,王 旭,等. 土钉墙支护技术室内模型试验对比研究[J]. 兰州工业学院学报,2015,22(1):23-28. doi: 10.3969/j.issn.1009-2269.2015.01.006 [6] JGJ 120—2012 建筑基坑支护技术规程[S]. 北京: 中国建筑工业出版社, 2012. [7] 林宗元. 岩土工程治理手册[M]. 北京: 中国建筑工业出版社, 2005. -
图(12) / 表(5)
计量
- 文章访问数: 161
- HTML全文浏览量: 33
- PDF下载量: 28
- 被引次数: 0
