冻土地基中锥管板条装配式基础抗拔承载性能试验研究

张学礼; 崔强; 张树林

doi:10.19509/j.cnki.dzkq.2022.0050

冻土地基中锥管板条装配式基础抗拔承载性能试验研究

doi: 10.19509/j.cnki.dzkq.2022.0050

张学礼^1,,
崔强^2, ,,
张树林³

基金项目:

国家电网公司科技项目"特高压直流工程换流站与线路基础的装配式模块关键技术研究" GCB17201700134

详细信息

作者简介:
张学礼(1982-), 男, 高级工程师, 主要从事电力线路工程设计工作。E-mail: zhangxueli310@163.com

通讯作者:
崔强(1980-), 男, 正高级工程师, 主要从事输变电工程试验检测及科研工作。E-mail: everjsl@126.com

中图分类号: TU432
计量
- 文章访问数: 421
- PDF下载量: 30
- 被引次数: 0
出版历程
- 收稿日期: 2021-02-05

Experimental research on uplift bearing capacity of the assembled foundation with cone tube and slab in frozen subsoil

摘要

摘要: 为了分析冻土地基中输电线路基础发生冻拔破坏的科学问题, 以锥管板条装配式基础为研究对象, 采用室内模型试验测试及分析的研究方法, 开展了不同环境温度下, 冻土地基的冻结试验和基础的上拔加载试验, 分析了地基温度场、位移场的分布特征以及基础抗拔承载力与温度之间的关系, 揭示出上拔荷载作用下冻土地基的破坏模式。研究结果表明: 冻结试验中, 模型基础的冻拔位移均小于周围地基土体的冻胀位移, 基础对地基土体的冻胀存在反约束作用, 距离基础越近, 约束作用越明显; 不同冻结环境温度下基础的上拔加载试验中, 抗拔极限承载力均随环境温度的降低近似呈线性增大, 增加速率接近1.8 kN/℃; 在冻结与上拔力双重作用下, 地基土体首先出现局部张拉破坏, 随着上拔荷载的不断增加, 地基土体逐渐由局部张拉破坏过渡为整体剪切破坏。研究成果可为这种形式的基础在冻土地基中的应用提供理论依据和实践经验。
- 冻土地基 /
- 锥管板条装配式基础 /
- 模型试验 /
- 冻胀量 /
- 荷载-位移曲线 /
- 抗拔承载性能
Abstract: Aiming at the scientific problem of transmission line foundation freeze-thaw failure in frozen subsoil, this paper takes an assembled foundation with cone tubes and slabs as the research object. The research method of the indoor model test and analysis is adopted, and a series of freezing tests and uplift loading tests of the model foundation are carried out under different ambient temperatures. The distribution characteristics of the temperature field and displacement field of the foundation and the relationship between the ultimate uplift capacity and temperature are analysed. Simultaneously, the failure mode of the frozen soil foundation under uplift load is also revealed. The research results show that in the freezing test, the displacement of the model foundation is less than the frost heave displacement of the surrounding foundation soil; the closer the distance from the foundation is, the stronger the frost heaving anti-restraint effect of the foundation is.In the uplift loading test of the foundation under different freezing ambient temperatures, the ultimate uplift capacity increases approximately linearly with the decrease in the ambient temperature, and the increase rate is close to 1.8 kN/℃. Under the double action of freezing and uplift, the foundation soil first exhibits local tensile failure, and with the increasing uplift load, the foundation soil gradually transitions from local tensile failure to overall shear failure. The results of this paper can provide a theoretical basis and practical experience for the application of this type of foundation in frozen subsoil.
- frozen subsoil /
- assembled foundation with cone tube and slab /
- model test /
- frost heaving /
- uplift load-displacement curve /
- ultimate uplift capacity

HTML全文

图 1 锥管板条装配式基础示意图

Figure 1. Schematic diagram of the assembled foundation with a cone tube and slab

下载: 全尺寸图片幻灯片

图 2 取样现场

Figure 2. Sampling site

下载: 全尺寸图片幻灯片

图 3 试验装置

Figure 3. Test device

下载: 全尺寸图片幻灯片

图 4 位移传感器布置示意图(数值单位: mm)

Figure 4. Schematic diagram of the displacement sensor layout

下载: 全尺寸图片幻灯片

图 5 温度传感器布置示意图(数值单位: mm)

Figure 5. Schematic diagram of the temperature sensor layout

下载: 全尺寸图片幻灯片

图 6 环境温度随时间变化曲线(图 5中T0传感器)

Figure 6. Change curve of ambient temperature with test time

下载: 全尺寸图片幻灯片

图 7 不同位置处地基温度随时间变化曲线(-10℃)

Figure 7. Change curve of soil surface temperature with time at different positions(-10℃)

下载: 全尺寸图片幻灯片

图 8 基础顶部与地基表面处上拔位移随时间的变化曲线

Figure 8. Change curve of foundation top and soil surface uplift displacements with test time

下载: 全尺寸图片幻灯片

图 9 地基上拔位移与距基础边缘距离之间的关系曲线

Figure 9. Relation curve between freeze-drawing displacement and distance from foundation edge

下载: 全尺寸图片幻灯片

图 10 地基基础表面最终冻胀量随温度变化曲线

Figure 10. Change curve of the final freeze-drawing of the foundation and soil surface with temperature

下载: 全尺寸图片幻灯片

图 11 地表冻胀裂缝

Figure 11. Frost heave cracks distributed on the soil surface

下载: 全尺寸图片幻灯片

图 12 不同环境温度下基础的荷载-位移曲线

Figure 12. Load-displacement curves of the test foundations under different ambient temperatures

下载: 全尺寸图片幻灯片

图 13 试验基础的抗拔极限承载力与环境温度关系曲线

Figure 13. Relation curve between the ultimate uplift capacity of the test foundation and ambient temperature

下载: 全尺寸图片幻灯片

图 14 试验结束后地表裂缝分布(-15℃)

Figure 14. Distribution of surface cracks after the test (-15℃)

下载: 全尺寸图片幻灯片

表 1 地基土样的物理力学指标

Table 1. Physical and mechanical indexes of the soil sample

指标	数值
相对密度	2.5
含水率/%	10.4
密度/(g·cm^-3)	1.5
液限/%	25.6
塑限/%	15.1
黏聚力/kN	5.9
内摩擦角/(°)	10.4
冻胀率/%	6.2

下载: 导出CSV

表 2 地基土样中可溶盐质量分数

Table 2. Percentage content of soluble salt in the soil sample

指标	w_B/%
Na⁺	0.015 6
K⁺	0.020 9
Mg²⁺	0.014 5
Ca²⁺	0.30
SO₄^2-	0.85
Cl^-	0.038 2

下载: 导出CSV

表 3 本次模型试验的相似参数

Table 3. Similar parameters of these model tests

参数	几何比C_l	时间比C_t	应力比C_σ	应变比C_ε
数值	1∶10	1∶100	1	1

下载: 导出CSV

表 4 3种不同温度下试验基础抗拔极限承载力及极限位移

Table 4. Ultimate uplift capacity and ultimate displacement of the test foundation at three different temperatures

参数	-5℃	-10℃	-15℃
抗拔极限承载力/kN	27	35	45
极限位移/mm	31	34	44

下载: 导出CSV

参考文献(27)

[1]	周盛涛, 方文, 蒋楠, 等. 冻融循环作用下砂岩单轴压缩破坏断口特征分形研究[J]. 地质科技通报, 2020, 39(5): 61-68. https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ202005009.htm Zhou S T, Fang W, Jiang N, et al. Fractal geometry study on uniaxial compression fracture characteristics of sandstone subjected to freeze-thaw cycles[J]. Bulletin of Geological Science and Technology, 2020, 39(5): 61-68(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DZKQ202005009.htm
[2]	朴昇昊, 张伟丽, 王永一, 等. 冻融循环对GFRP锚杆锚固性能影响的试验研究[J/OL]. 地质科技通报, 2021: 1-7[2022-03-11]. doi: 10.19509/j.cnki.dzkq.2021.0055 Piao S H, Zhang W L, Wang Y Y, et al. Experimental study on the influence of freeze-thaw cycles on the anchoring performance of GFRP bolts[J/OL]. Bulletin of Geological Science and Technology, 2021: 1-7[2022-03-11]. doi: 10.19509/j.cnki.dzkq.2021.0055(Chinese with English abstract).
[3]	Isaev O N, Volkov F E, Minkin M A. Static-penetration determination of the bearing capacity of piles in plastic-frozen soils[J]. Soil Mechanics and Foundation Engineering, 1987, 24(5): 194-198. doi: 10.1007/BF01787142
[4]	Thompson S R, Tart R G. Driven pile capacities in warm permafrost in Komi republic, Russia[C]//Anon. Proceedings of the 8th International Conference on Cold Regions Engineering. Alaska, USA: ASCE, 1996: 254-265.
[5]	Titi H, Wathugala G. Numerical procedure for predicting pile capacity-setup/freeze. Transportation Research Record[J]. Journal of the Transportation Research Board, 1999, 1663: 25-32. doi: 10.3141/1663-04
[6]	Li N, Xu B. A new type of pile used in frozen soil foundation[J]. Cold Reg. Sci. Technol., 2008, 53(3): 355-368. doi: 10.1016/j.coldregions.2007.10.005
[7]	Chen G S, Davis D, Hulsey J L. Measurement of frozen soil-pile dynamic properties: A system identification approach[J]. Cold Reg. Sci. Technol., 2012, 70: 98-106. doi: 10.1016/j.coldregions.2011.08.007
[8]	Gu Q, Yang Z, Peng Y. Parameters affecting laterally loaded piles in frozen soils by an efficient sensitivity analysis method[J]. Cold Reg. Sci. Technol., 2016, 121: 42-51. doi: 10.1016/j.coldregions.2015.10.006
[9]	赖远明, 朱元林, 吴紫汪. 桩基冻胀力三维问题的积分方程解法[J]. 铁道学报, 1998, 20(6): 432-437. https://www.cnki.com.cn/Article/CJFDTOTAL-TDXB806.015.htm Lai Y M, Zhu Y L, Wu Z W. A simple integral equation method for three-dimensional frost heaving force problem of piles[J]. Journal of the China Railway Society, 1998, 20(6): 432-437(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-TDXB806.015.htm
[10]	李洪升, 刘增利, 朱元林. 冻土断裂学在桩基冻拔稳定性计算中的应用[J]. 冰川冻土, 1998, 20(2): 112-115. Li H S, Liu Z L, Zhu Y L. Application of the fracture Mechanics of frozen soil to the calculation of stability of pile foundation uplift[J]. Journal of Glaciology and Geocryology, 1998, 20(2): 112-115(in Chinese with English abstract).
[11]	程永锋, 鲁先龙, 刘华清, 等. 青藏铁路110 kV输电线路冻土桩基模型试验研究[J]. 岩石力学与工程学报, 2004, 23(增刊1): 4378-4382. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2004S1023.htm Chen Y F, Lu X L, Liu H Q, et al. Model test study on pile foundation of 110 kV transmission line of Qinghai-Tibet railway in frozen soils[J]. Chinese Journal of Rock Mechanics and Engineering, 2004, 23(S1): 4378-4382(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2004S1023.htm
[12]	汪仁和, 王伟, 程永锋. 冻土中单桩抗拔承载力的模型试验研究[J]. 冰川冻土, 2006, 28(5): 766-771. doi: 10.3969/j.issn.1000-0240.2006.05.021 Wang R H, Wang W, Cheng Y F. Model study of tensile bearing capacity of a single pile under frozen condition[J]. Journal of Glaciology and Geocryology, 2006, 28(5): 766-771(in Chinese with English abstract). doi: 10.3969/j.issn.1000-0240.2006.05.021
[13]	蒋代军, 郭春香. 青藏高原多年冻土区单桩承载力的长期稳定性[J]. 长安大学学报: 自然科学版, 2016, 36(1): 59-65. https://www.cnki.com.cn/Article/CJFDTOTAL-XAGL201602009.htm Jiang D J, Guo C X. Long-term stability of bearing capacity of single pile in permafrost area on Qinghai-Tibetan Plateau[J]. Journal of Chang'an University: Natural Science Edition, 2016, 36(2): 59-65(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-XAGL201602009.htm
[14]	王腾飞, 刘建坤, 邰博文. 螺旋桩冻拔特性的模型试验研究[J]. 岩土工程学报, 2018, 40(6): 1084-1092. Wang T F, Liu J K, Tai B W, et al. Model experiment on frost jacking behaviors of helical steel pile[J]. Chinese Journal of Geotechnical Engineering, 2018, 40(6): 1084-1092(in Chinese with English abstract).
[15]	周有才. 基侧斜面基础克服切向冻胀力的最小夹角[J]. 建筑技术, 1990, 17(10): 23-25, 54. https://www.cnki.com.cn/Article/CJFDTOTAL-JZJI199010004.htm Zhou Y C. The minimum angle between the tangent frost heaving force and the slope foundation on the base side[J]. Building Technology, 1990, 17(10): 23-25, 54(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-JZJI199010004.htm
[16]	王力生, 张云芳, 刘鸿绪. 斜面基础防切向冻胀力的受力分析[J]. 低温建筑技术, 1995(3): 30-32. https://www.cnki.com.cn/Article/CJFDTOTAL-DRAW503.012.htm Wang L S, Zhang Y F, Liu H X. Stress analysis of anti-tangential frost heave force of inclined foundation[J]. Low Temperature Building Technology, 1995(3): 30-32(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-DRAW503.012.htm
[17]	何晓光, 张洪玉, 于宏伟. 桩基冻拔及补救措施[J]. 水利科技与经济, 2002, 8(3): 184-185. https://www.cnki.com.cn/Article/CJFDTOTAL-SLKY200203035.htm He X G, Zhang H Y, Yu H W. Pile foundation freeze drawing and remedial measures[J]. Water Conservancy Science and Technology and Economy, 2002, 8(3): 184-185(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-SLKY200203035.htm
[18]	苏凯, 张建明, 冯文杰, 等. 多年冻土区斜坡地带锥柱基础初始回冻过程模型试验[J]. 岩土工程学报, 2013, 44(4): 794-799. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201304030.htm Su K, Zhang J M, Feng W J, et al. Model tests on initial freezing process of column foundation on slope in permafrost regions[J]. Chinese Journal of Geotechnical Engineering, 2013, 44(4): 794-799(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201304030.htm
[19]	徐会永, 孙义红, 张家琦, 等. 季节性冻土地区通信铁塔地基设计及施工处理探讨[J]. 特种结构, 2008, 25(2): 29-31. https://www.cnki.com.cn/Article/CJFDTOTAL-TZJG200802013.htm Xu H Y, Sun Y H, Zhang J Q, et al. Discussion on foundation design and construction treatment of communication tower in seasonally frozen soil area[J]. Special Structures, 2008, 25(2): 29-31(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-TZJG200802013.htm
[20]	李孝臣. 季节冻土区高压输电杆塔斜面基础研究[D]. 哈尔滨: 哈尔滨工业大学, 2008. Li X C. Study on slope foundation of high voltage transmission tower in seasonal frozen soil area[D]. Harbin: Harbin University of Technology, 2008(in Chinese with English abstract).
[21]	中国电力科学研究院有限公司. 一种高寒地区特高压直流输电线路铁塔的装配装置[P]. 中国, 201911318829.5, 2019-12-19. China Electric Power Research Institute Co., Ltd. A kind of assembling device for UHVDC transmission tower in high cold area[P]. Chinese, 201911318829.5, 2019-12-19(in Chinese with English abstract).
[22]	建设综合勘查研究设计院. 岩土工程勘察规范: GB 50021-2001[S]. 北京: 中国建筑工业出版社, 2009. Comprehensive Institute of Geotechnical Investigation and Surveying. Code for investigation of geotechnical engineering: GB 50021-2001[S]. Beijing: China Construction Industry Press(in Chinese).
[23]	中国电力科学研究院有限公司. 一种多功能冻土模型试验装置及其试验方法[P]. 中国, 201911015894.0, 2019-12-19. China Electric Power Research Institute Co., Ltd. A multifunctional frozen soil model test device and its test method[P]. Chinese, 201911015894.0, 2019-12-19(in Chinese with English abstract).
[24]	天气网, http://www.tianqi.com/qiwen/city_hailaer/
[25]	中华人民共和国行业标准编写组. 架空输电线路基础设计技术规程: DL/T 5219-2014[S]. 北京: 中国电力出版社, 2015. The Professional Standards Compilation Group of People's Republic of China. Technical code for design of foundation of overhead transmission line: DL/T 5219-2014[S]. Beijing: China Eclectic Power Press, 2015(in Chinese).
[26]	李东庆, 朱林楠. 荷载作用下冻土模型试验相似分析[J]. 自然科学进展, 1994, 4(3): 322-327. https://www.cnki.com.cn/Article/CJFDTOTAL-ZKJZ199403011.htm Li D Q, Zhu L N. Similitude analysis of modeling test for pressure in the freezing-thawing process of soil[J]. Journal of Glaciologyand Geocryology, 1994, 4(3): 322-327(in Chinese with English abstract). https://www.cnki.com.cn/Article/CJFDTOTAL-ZKJZ199403011.htm
[27]	马巍, 王大雁. 冻土力学[M]. 北京: 科学出版社, 2014. Ma W, Wang D Y. Frozen soil mechanics[M]. Beijing: Science Press, 2014(in Chinese).