The friction strength characteristics of gravity anchorages of suspension bridges at the contact surface between concrete and gravel soil have a decisive influence on the slip resistance stability of the anchorages. In order to study the friction strength characteristics of the contact surface between gravel soil and anchor concrete and to determine the friction coefficient of the contact surface, this paper carried out the shear fracture test, shear test, and reciprocating shear test of the contact surface between concrete and gravel soil, analyzed the change rule of the stress-displacement law of the three test phases, and utilized the least-squares method to fit the τ vs. σ relationship curve to obtain the friction coefficient of the contact surface. The result shows that in the shear resistance test, the contact surface showed strain softening phenomenon and pressure embedding effect in the shear damage process, and the depth of pressure embedding ranged from 2 mm to 5 mm; in the shear resistance test and reciprocating shear test, the contact surface did not show significant strain softening phenomenon, and the concrete was mainly sliding horizontally on the contact surface; in the shear section, the shear resistance, and the three phases of reciprocating shear test, the friction coefficient of the contact surface was calculated by the relationship curve between the concrete and the adhesion (c) of the contact surface decreased significantly, and the value of the friction coefficient f decreased at a rate of 1% to 2%, indicating that the occlusion and embedment of the contact surface was weakening; the value of the pure friction strength parameter f (0.48) in the reciprocating shear test was selected as the friction coefficient of the contact surface between concrete and gravel soil.
Yang Xingyu
,
Chen Peng
,
Guo Xifeng
,
Zeng Yong
,
Zhang Jianrong
. In-Situ Shear Test Study on the Contact Surface Between Gravity Anchor and Gravel Soil of a Suspension Bridge[J]. Chinese Journal of Underground Space and Engineering, 2024
, 20(6)
: 1928
-1934
.
DOI: 10.20174/j.JUSE.2024.06.18
[1] Potyondy J G. Skin friction between various soils and construction materials[J]. Geotechnique,1961,11(4):339-353.
[2] Chen X B, Zhang J S, Xiao Y J, et al. Effect of roughness on shear behavior of red clay-concrete interface in largescale direct shear tests[J]. Canadian Geotechnical Journal, 2015, 52(8): 1122-1135.
[3] Cen D F, Huang D, Ren F. Shear deformation and strength of the interphase between the soil-rock mixture and the benched bedrock slope surface[J]. Acta Geotechnica, 2017, 12(2):391-413.
[4] 杨忠平,蒋源文,李涛琪,等.土石混合体-基岩界面剪切力学特性试验研究[J].岩土工程学报,2020,42(10):1947-1954.(Yang Zhongping, Jiang Yuanwen, Li Shiqi, et al. Experimental study on shear mechanical properties of soil-rock mixture-bedrock interface[J]. Chinese Journal of Geotechnical Engineering, 2020, 42(10): 1947-1954.(in Chinese))
[5] 中华人民共和国住房和城乡建设部. 建筑地基基础设计规范(GB50007-2011)[S].北京:中国建筑工业出版社, 2011.(Ministry of Housing and Urban-Rural Development of the People's Republic of China. Code for design of building foundation[S]. Beijing: China Construction Industry Press, 2011. (in Chinese))
[6] 中华人民共和国交通运输部. 公路桥涵地基与基础设计规范(JTG3363-2019)[S].北京:人民交通出版社, 2019. (Ministry of Communications of the People's Republic of China. Specifications for design of foundation of highway bridges and culverts[S]. Beijing: China Communications Press, 2019. (in Chinese))
[7] 任明辉. 土石混合体剪切强度的尺寸效应研究[D].徐州:中国矿业大学, 2019.(Ren Minghui. Study on the scale effect on the shear strength of soil-rock mixture[D]. Xuzhou: China University of Mining and Technology, 2019. (in Chinese))
[8] 陈有亮. 虎门大桥东锚碇重力锚及基岩的稳定性[A]// 第五届全国结构工程学术会议论文集(第三卷)[C].1996:142-148.(Chen Youliang. Stability of the east gravity concrete anchor and bedrock of Humen Bridge[A]// Proceedings of the Fifth National Academic Conference on Structural Engineering[C]. 1996:142-148.(in Chinese))
[9] 王保田,朱珍德,张福海,等.花岗岩与混凝土胶结面抗剪强度的试验研究[J].岩土力学,2004,25(11):1717-1721.(Wang Baotian, Zhu Zhende, Zhang Fuhai, et al. Experiment on the resistance of the base-contact surface of the anchors and rocks surface of the anchors and rocks[J].Rock and Soil Mechanics, 2004, 25(11): 1717-1721. (in Chinese))
[10] 王艳芬,马远刚.西堠门大桥锚碇岩基原位试验[J].桥梁建设,2009(增2):67-71.(Wang Yanfen, Ma Yuangang. In-situ tests for rock foundation of anchorage of Xihoumen Bridge[J].Bridge Construction,2009(Supp. 2):67-71. (in Chinese))
[11] 刘洋,赵明阶,郑升宝.青草背长江大桥北锚碇摩阻力试验[J].重庆交通大学学报(自然科学版), 2011, 30 (5):911-915.(Liu Yang, Zhao Mingjie, Zheng Shengbao. Test study on the friction resistance of the north concrete anchor of Qingcaobei Yangtze River Bridge[J]. Journal of Chongqing Jiaotong University(Natural Science), 2011, 30(5):911-915.(in Chinese))
[12] 谭新,徐厚庆,彭伟.悬索桥重力式锚碇摩阻系数试验及取值方法[J].地下空间与工程学报,2015,11(增2):549-552, 584. (Tan Xin, Xu Houqing, Peng Wei. The test and calculating method for gravity anchorages frictional coefficient of suspension bridge[J]. Chinese Journal of Underground Space and Engineering,2015,11(Supp. 2):549-552, 584. (in Chinese))
[13] 朱武俊,王晅,张家生,等.弃渣混合料与混凝土接触面剪切力学特性[J]. 哈尔滨工业大学学报, 2023, 55 (2): 98-107. (Zhu Wujun, Wang Xuan, Zhang Jiasheng, et al.Shear mechanical behavior of interface between spoil mixture and concrete[J]. Journal of Harbin Institute of Technology, 2023,55(2):98-107.(in Chinese))
[14] 成浩,王晅,张家生,等.考虑粗糙度影响的不同土与混凝土界面大型直剪试验研究[J].工程科学与技术,2019,51(5):117-125.(Cheng Hao, Wang Xuan, Zhang Jiasheng, et al. Large-scale direct shear tests of interfaces between different soils and concrete considering roughness effect[J]. Advanced Engineering Sciences,2019,51(5):117-125. (in Chinese))
[15] 江强强,徐杨青,王浩.不同含石量条件下土石混合体剪切变形特征的试验研究[J].工程地质学报, 2020,28(5): 951-958.(Jiang Qiangqiang, Xu Yangqing, Wang Hao. Research on shear deformation characteristics of soil-rock mixtures under different stone contents[J].Journal of Engineering Geology, 2020, 28(5):951-958. (in Chinese))
[16] 杨忠平,李进,刘浩宇,等.土石混合体—基岩界面剪切力学特性块石尺寸效应[J].岩土力学, 2023, 44(4):965-974.(Yang Zhongping, Li Jin, Liu Haoyu, et al. Influence of the block stone size on shear mechanical behavior of soil-rock mixture-bedrock interface[J].Chinese Journal of Geotechnical Engineering, 2023,44 (4):965-974.(in Chinese))
