Mechanical characteristic test of tunnel support structure in weak loess stratum
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摘要: 为研究软弱黄土隧道支护结构的受力特性, 优化黄土隧道设计理论, 以西宁过境高速公路某黄土隧道为依托, 选取杂填土段、深埋段和浅埋段进行了大规模的现场测试, 从支护受力的空间分布、时间分布、计算方法以及对比验证等方面, 对围岩与初支接触压力、初支与二衬接触压力及二衬和仰拱混凝土的应变进行了系统的研究。分析结果表明: 拱顶、拱肩处的压力值较大, 是黄土隧道最危险的部位, 容易发生坍塌; 围岩压力计算值与实测值相差较大, 现有方法在计算黄土断面围岩压力时存在较大的误差; 深埋段围岩压力稳定时间最短, 浅埋段次之, 杂填土段时间最长; 软弱黄土隧道“新奥法”原理指导下, “强初支, 弱二衬”设计理念的采用, 使二衬荷栽承担比例控制在11%~36%范围内, 充分发挥了初支对围岩变形的抑制作用, 二衬仍作为安全储备。Abstract: In order to analyze the mechanical characteristics of tunnel support structure in weak loess stratum and optimize the design theory of loess tunnel, large scale field tests of the sections of miscellaneous fill, deep depth and shallow depth were conducted for a loess tunnel of the highway through Xining City. In the aspects of space distribution, time distribution, calculation method and contrast verification, the contact pressure between surrounding rock and primary liner, the contact pressure between primary liner and secondary liner, and the strains of secondary liner and inverted arch were systematically studied. Analysis result shows that the vault and spandrel are the most dangerous parts of loess tunnel for their large pressures and prone to collapse. The calculated values of surrounding rock pressure are very different from the measured values, and the existing method has a big error in the calculation of surrounding rock pressure at the loess section. The time for surrounding rock pressure to stabilize is shorter at deep depth section than the value at shallow depth section, and the time at the section of miscellaneous fill is the longest. Following the guidance of New Austrian Tunnelling Method for the loess tunnel and the design concept of "strong primary liner and weak secondary liner", the loading proportions of the secondary liner have been kept in the range of 11%-36% and the primary liner has played an important role in controlling the deformation of surrounding rock. The secondary liner has played as safety reserve.
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Key words:
- highway tunnel /
- weak loess /
- support structure /
- mechanical characteristic
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图 3 各断面位置的初支压力分布
Figure 3. Distributions of primary liner pressures at different sections
图 4 围岩与初支接触压力-时间曲线
Figure 4. Contact pressure-time curves between surrounding rock and primary liner
图 6 初支与二衬接触压力分布
Figure 6. Distributions of contact pressures between primary liner and secondary liner
图 7 各断面位置初支与二衬接触压力分布
Figure 7. Distributions of constact pressures between primary liner and secondary liner at different sections
图 8 初支与二衬接触压力-时间曲线
Figure 8. Contact pressure-time curves between primary liner and secondary liner
表 1 隧道支护参数
Table 1. Parameters of tunnel liner and support
表 2 测试断面上覆土层厚度
Table 2. Thicknesses of covering soils at test sections
表 3 竖向围岩压力
Table 3. Pressures of vertical surround ling rocks
表 4 杂填土段断面初支与二衬接触压力
Table 4. Contact pressures of primary liner and secondary liner at miscellaneous fill sections
表 5 深埋段断面初支与二衬接触压力
Table 5. Contact pressures of primary liner and secondary liner at deep depth sections
表 6 浅埋段断面初支与二衬接触压力
Table 6. Pressures of primary liner and secondary liner at shallow depth sections
表 7 黄土隧道二衬承受的荷载比
Table 7. Load ratios of secondlary liners of loess tunnels
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[1] 韩桂武, 刘斌, 范鹤. 浅埋黄土隧道衬砌结构受力分析[J]. 岩石力学与工程学报, 2007, 26(增1): 3250-3256. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2007S1098.htmHAN Gui-wu, LIU Bin, FAN He. Mechanical characteristics of tunnel lining structure in shallow-buried loess area[J]. Chinese Journal of Rock Mechanics and Engineering, 2007, 26(S1): 3250-3256. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX2007S1098.htm [2] 李鹏飞, 张顶立, 赵勇, 等. 大断面黄土隧道二次衬砌受力特性研究[J]. 岩石力学与工程学报, 2010, 29(8): 1690-1696. https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201008026.htmLI Peng-fei, ZHANG Ding-li, ZHAO Yong, et al. Study of mechanical characteristics of secondary lining of large-section loess tunnel[J]. Chinese Journal of Rock Mechanics and Engineering, 2010, 29(8): 1690-1696. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YSLX201008026.htm [3] KRUSE G A M, DIJKSTRA T A, SCHOKKING F. Effects of soil structure on soil behaviour: illustrated with loess, glacially loaded clay and simulated flaser bedding examples[J]. Engineering Geology, 2007, 91(1): 34-45. doi: 10.1016/j.enggeo.2006.12.011 [4] LI Rong-jian, LIU Jun-ding, YAN Rui, et al. Characteristics of structural loess strength and preliminary framework for joint strength formula[J]. Water Science and Engineering, 2014, 7(3): 319-330. [5] DUSAN B, ZORAN B, ĈEBAŠEK V, et al. Characterisation of collapsing loess by seismic dilatometer[J]. Engineering Geology, 2014, 181: 180-189. doi: 10.1016/j.enggeo.2014.07.011 [6] 赵占厂, 谢永利, 杨晓华, 等. 黄土公路隧道衬砌受力特性测试研究[J]. 中国公路学报, 2004, 17(1): 66-69. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200401016.htmZHAO Zhan-chang, XIE Yong-li, YANG Xiao-hua, et al. Observation research on the mechanical characteristic of highway tunnel lining in loess[J]. China Journal of Highway and Transport, 2004, 17(1): 66-69. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200401016.htm [7] 来弘鹏, 谢永利, 杨晓华. 黄土公路隧道受力特性测试[J]. 长安大学学报: 自然科学版, 2005, 25(6): 53-56. https://www.cnki.com.cn/Article/CJFDTOTAL-XAGL200506012.htmLAI Hong-peng, XIE Yong-li, YANG Xiao-hua. Mechanical characteristic of highway tunnel in loess[J]. Journal of Chang'an University: Natural Science Edition, 2005, 25(6): 53-56. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-XAGL200506012.htm [8] 陈建勋, 姜久纯, 罗彦斌, 等. 黄土隧道洞口段支护结构的力学特性分析[J]. 中国公路学报, 2008, 21(5): 75-80. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200805015.htmCHEN Jian-xun, JIANG Jiu-chun, LUO Yan-bin, et al. Mechanics characteristic analysis of support structure of loess tunnel entrance[J]. China Journal of Highway and Transport, 2008, 21(5): 75-80. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200805015.htm [9] 杨建民, 喻渝, 谭忠盛, 等. 大断面深浅埋黄土隧道围岩压力试验研究[J]. 铁道工程学报, 2009, 2: 76-79. https://www.cnki.com.cn/Article/CJFDTOTAL-TDGC200902018.htmYANG Jian-min, YU Yu, TAN Zhong-sheng, et al. Experimental research on the surrounding rock pressure of large sectional loess tunnel under deep and shallow submersion[J]. Journal of Railway Engineering Society, 2009, 2: 76-79. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-TDGC200902018.htm [10] 李鹏飞, 赵勇, 张顶立, 等. 基于现场实测数据统计的隧道围岩压力分布规律研究[J]. 岩石力学与工程学报, 2013, 32(7): 1392-1399. doi: 10.3969/j.issn.1000-6915.2013.07.014LI Peng-Fei, ZHAO Yong, ZHANG Ding-li, et al. Study of distribution laws of tunnel surrounding rock pressure based on field measured data statistics[J]. Chinese Journal of Rock Mechanics and Engineering, 2013, 32(7): 1392-1399. (in Chinese) doi: 10.3969/j.issn.1000-6915.2013.07.014 [11] 马士伟, 韩学诠, 廖凯. 浅埋大断面黄土隧道防塌方实时监测预警[J]. 现代隧道技术, 2014, 51(2): 11-15, 22. https://www.cnki.com.cn/Article/CJFDTOTAL-XDSD201402003.htmMA Shi-wei, HAN Xue-quan, LIAO Kai. Real-time monitoring and early alarms for collapse prevention in a shallow loess tunnel with a large section[J]. Modern Tunnelling Technology, 2014, 51(2): 11-15, 22. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-XDSD201402003.htm [12] 黄运章, 刘春龙, 张群, 等. 某黄土隧道塌方处理措施及原因分析[J]. 土工基础, 2012, 26(6): 30-33. https://www.cnki.com.cn/Article/CJFDTOTAL-TGJC201206011.htmHUANG Yun-zhang, LIU Chun-long, ZHANG Qun, et al. Analyses and mitigations of a tunnel collapse in loess[J]. Soil Engineering and Foundation, 2012, 26(6): 30-33. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-TGJC201206011.htm [13] 李烨, 许崇帮. 大酉山隧道围岩长期变形分析[J]. 公路交通科技, 2013, 30(12): 120-124. https://www.cnki.com.cn/Article/CJFDTOTAL-GLJK201312018.htmLI Ye, XU Chong-bang. Analysis of long-term deformation of tunnel surrounding rock of Dayoushan Tunnel[J]. Journal of Highway and Transportation Research and Development, 2013, 30(12): 120-124. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GLJK201312018.htm [14] LUO Yan-bin, CHEN Jian-xun. Calculation method of horizontal surrounding rock pressure for tunnel[J]. Journal of Traffic and Transportation Engineering, 2012, 12(2): 10-17. [15] 赖金星, 杨晓华. 丹(东)拉(萨)国道主干线西宁过境公路大有山隧道监控量测报告总结[R]. 西安: 长安大学, 2010.LAI Jin-xing, YANG Xiao-hua. Monitoring and measuring report of Dayoushan Tunnel[R]. Xi'an: Chang'an University, 2010. (in Chinese) [16] FENG Shi-jin, DU Feng-lei, SHI Zhen-ming, et al. Field study on the reinforcement of collapsible loess using dynamic compaction[J]. Engineering Geology, 2015, 185(1): 105-115. [17] 谢家烋. 浅埋隧道的地层压力[J]. 土木工程学报, 1964, 10(6): 58-70. https://www.cnki.com.cn/Article/CJFDTOTAL-TMGC196406006.htmXIE Jia-xiao. Stratum pressure of shallow tunnel[J]. China Civil Engineering Journal, 1964, 10(6): 58-70. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-TMGC196406006.htm [18] TERZAGHI K. Theoretical Soil Mechanics[M]. New York: Wiley, 1943. [19] 赵占厂. 黄土公路隧道结构工程性状研究[D]. 西安: 长安大学, 2004.ZHAO Zhan-chang. Study on engineering properties of highway tunnel in loess[D]. Xi'an: Chang'an University, 2004. (in Chinese) [20] 来弘鹏, 谢永利, 刘苗, 等. 黄土地区浅埋暗挖地铁隧道衬砌受力分析[J]. 岩土工程学报, 2011, 33(8): 1167-1172. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201108005.htmLAI Hong-peng, XIE Yong-li, LIU Miao, et al. Mechanical characteristics for linings of shallow excavation metro tunnel in loess region[J]. Chinese Journal of Geotechnical Engineering, 2011, 33(8): 1167-1172. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC201108005.htm -
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