Study of influence factors on tendons-soil interface characteristic
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摘要: 以整体式单向聚乙烯土工格栅与钢塑复合加筋带为加筋材料, 以含细粒土砂为填料, 设计了高速公路拓宽工程加筋边坡。通过室内拉拔试验对填料在不同含水量和不同压实度条件下与土工格栅之间的摩擦特性进行分析, 并对比了原样土工格栅、去除横肋的土工格栅和土工加筋带三者之间的界面摩擦特性。分析结果表明: 在填料含水量高于填料的最佳含水量时, 筋土界面强度随着含水量增加而降低, 且变化明显, 随着填料压实度的提高而不断增强, 加筋效果也明显增强; 土工格栅的横肋对筋土界面特性影响非常明显, 贡献率高达50%以上。Abstract: A rib-reinforced slope in expressway's widening engineering was designed, in which holistic and unilateral polyethylene geogrid and steel-plastic composite geobelt were taken as enhancement materials and sand with fine-grained soil was taken as fill.The friction performance of tendons-soil interface was analysed by pull-out test in laboratory under different water contents and compactions.The enhancement effects of original geogrid, the one without horizontal ribs and reinforcement geobelt were compared.It is found that when the fill's water content is higher than its optimum moisture content, the tendons-soil interface strength reduces with the increase of water content, which is obvious.With the rise of the fill's compaction, the interface strength increases unceasingly and the reinforcement effect is distinct.The horizontal ribs' contribution rate to the interface characteristic of reinforcement soil is over 50%.
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表 1 不同含水量和压实度下的拉拔试验对比方案
Table 1. Comparison of pull-out test programmes under different water contents and compactions
试验组号 填料 筋材 含水量/% 压实度/% T1 含细粒土砂 土工格栅 11.5 85 T2 14.5 T3 19.5 T4 11.5 80 T5 11.5 90 表 2 不同加筋材料拉拔试验对比方案
Table 2. Comparison of pull-out test programmes under different tendons materails
试验组号 填料 筋材 含水量/% 压实度/% T4 含细粒土砂 土工格栅 11.5 80 T6 拉筋带 表 3 含肋与去肋土工格栅拉拔试验对比方案
Table 3. Comparison of pull-out test programmes of geogrids with horizontal ribs or not
试验组号 填料 筋材 含水量/% 压实度/% T7 含细粒土砂 含肋土工格栅 19.5 85 T8 去肋土工格栅 表 4 不同含水量下的筋土界面参数
Table 4. Tendons-soil interface parameters under different water contents
含水量/% 11.5 14.5 19.5 粘聚力/kPa 2.81 2.80 1.92 界面摩擦系数 0.43 0.34 0.24 表 5 不同压实度下的筋土界面参数
Table 5. Tendons-soil interface parameters under different compactions
压实度/% 80 85 90 粘聚力/kPa 1.95 2.81 3.24 界面摩擦系数 0.31 0.43 0.52 表 6 不同加筋材料下的筋土界面参数
Table 6. Tendons-soil interface parameters under different tendons materials
筋材类型 土工格栅 拉筋带 粘聚力/kPa 2.01 0.61 界面摩擦系数 0.31 0.27 表 7 土工格栅含肋与否的筋土界面参数
Table 7. Tendons-soil interface parameters under geogrids with horizontal ribs or not
土工格栅类型 含肋格栅 去肋格栅 粘聚力/kPa 1.92 0.95 界面摩擦系数 0.24 0.12 -
[1] SOLDOSSER F, LONG N T. Recent results in French research on reinforced earth[J]. Journal of the Construction Division, 1974, 100(3): 223-237. doi: 10.1061/JCCEAZ.0000429 [2] 吴景海, 陈环, 王玲娟, 等. 土工合成材料与土界面作用特性的研究[J]. 岩土工程学报, 2001, 23(1): 89-93. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200101020.htmWUJing-hai, CHEN Huan, WANG Ling-juan, et al. Study on soil interaction characteristics of geosynthetics[J]. Chinese Journal of Geotechnical Engineering, 2001, 23(1): 89-93. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC200101020.htm [3] 邹静蓉, 刘拓瑜, 冷伍明. 土与土工格栅相互作用的模型试验研究[J]. 铁道科学与工程学报, 2005, 2(3): 51-55. https://www.cnki.com.cn/Article/CJFDTOTAL-CSTD200503009.htmZOUJing-rong, LI U Tuo-yu, LENG Wu-ming. The model test research oninteraction of soil and geogrid[J]. Journal of Rail way Science and Engineering, 2005, 2(3): 51-55. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-CSTD200503009.htm [4] 阎树旺, BEN B. 土工格栅与土相互作用的有限元分析[J]. 岩土工程学报, 1997, 19(6): 56-61. https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC706.009.htmYAN Shu-wang, BEN B. Finite-element modelling of soil-geogrid interaction with application to interpret the pullout behaviour of geogrids[J]. Chinese Journal of Geotechnical Engineering, 1997, 19(6): 56-61. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTGC706.009.htm [5] 桂晓刚, 邵生俊, 刘奉银. 加筋土钢塑筋带拉拔特性的室内模型试验研究[J]. 西安理工大学学报, 2007, 23(4): 422-426. doi: 10.3969/j.issn.1006-4710.2007.04.020GUI Xiao-gang, SHAO Sheng-jun, LI U Feng-yin. The inlab model test of the retaining wall of expansive reinforcement soil[J]. Journal of Xi an University of Technology, 2007, 23(4): 422-426. (in Chinese) doi: 10.3969/j.issn.1006-4710.2007.04.020 [6] 张孟喜, 孙遇祺, 李国祥, 加筋土挡墙工作机理的室内试验研究[J]. 铁道学报, 1999, 21(5): 79-82.ZHANG Meng-xi, SUN Yu-qi, LI Guo-xiang. Experi mental study of the fundamental mechanismof reinforced earth retain-ing walls[J]. Journal of the China Rail way Society, 1999, 21(5): 79-82. (in Chinese) [7] 杨果林, 王永和. 加筋土筋材工程特性试验研究[J]. 中国公路学报, 2001, 14(3): 11-16. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200103003.htmYANG Guo-lin, WANG Yong-he. Study of engineering char-acteristic of material used reinforced earth[J]. China Journal of Highway and Transport, 2001, 14(3): 11-16. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200103003.htm [8] 杨广庆, 周亦涛, 周乔勇, 等. 土工格栅加筋土挡墙试验研究[J]. 岩土力学, 2009, 30(1): 206-210. https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX200901047.htmYANG Guang-qing, ZHOU Yi-tao, ZHOU Qiao-yong, et al. Experi mental research on geogrid reinforced earth retaining wall[J]. Rock and Soil Mechanics, 2009, 30(1): 206-210. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-YTLX200901047.htm [9] 张茹, 何昌荣, 谢嘉琼, 等. 加筋土土工带的拉拔试验研究[J]. 四川大学学报: 工程科学版, 2002, 34(4): 26-29. https://www.cnki.com.cn/Article/CJFDTOTAL-SCLH200204006.htmZHANG Ru, HE Chang-rong, XIE Jia-qiong, et al. Study on geobelt reinforced soil by pul-out tests[J]. Journal of Sichuan University: Engineering Science Edition, 2002, 34(4): 26-29. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-SCLH200204006.htm [10] 高翔, 石名磊, 刘松玉. 加筋粘性土筋土界面剪切特性的试验研究[J]. 公路交通科技, 2002, 19(5): 8-10. https://www.cnki.com.cn/Article/CJFDTOTAL-GLJK200205002.htmGAO Xiang, SHI Ming-lei, LI USong-yu. Study on cohesive soil interaction shear characteristics of geosynthetics[J]. Journal of Highway and Transportation Research and Devel-opment, 2002, 19(5): 8-10. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GLJK200205002.htm [11] 凌天清. 公路高大加筋土挡墙设计方法的研究[J]. 中国公路学报, 2000, 13(2): 13-15, 19. https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200002003.htmLI NG Tian-qing. Research on high reinforced earth retaining wall design methods in highway engineering[J]. China Journal of Highway and Transport, 2000, 13(2): 13-15, 19. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-ZGGL200002003.htm [12] 冯光乐, 凌天清, 许志鸿, 等. 土工合成材料处理桥头过渡段路基离心模型试验研究[J]. 公路交通科技, 2003, 20(5): 10-14. https://www.cnki.com.cn/Article/CJFDTOTAL-GLJK200305003.htmFENG Guang-le, LI NG Tian-qing, XU Zhi-hong, et al. Centrifugal test study on bridge approach embankment disposed with geosynthetics[J]. Journal of Highway and Transportation Research and Development, 2003, 20(5): 10-14. (in Chinese) https://www.cnki.com.cn/Article/CJFDTOTAL-GLJK200305003.htm -