朱鸿鹄1,2，张诚成1，裴华富3，周游1，施斌1
(1. 南京大学地球科学与工程学院，江苏 南京 210093；2. 地质灾害防治与地质环境保护国家重点实验室（成都理工大学），四川 成都 610059；3. 香港理工大学土木及结构工程学系，香港)
摘要 由于传统土钉材料存在易腐蚀、耐久性差等缺点，近年来以GFRP为代表的新型土钉材料得到了高度重视。针对GFRP土钉受力特性，运用双曲线模型描述其在拉拔过程中剪应力–剪应变关系，采用数值方法求解拉拔控制方程，从而确定轴力、剪应力及位移沿钉长的分布。同时，通过室内GFRP模型土钉的拉拔试验，验证了该模型预测结果的准确性。在此基础上，对土钉直径、土–钉界面抗剪强度、土–钉模量比等参数进行了参数分析，并针对GFRP土钉容许拉拔力的确定提出了按位移控制的思路。
关键词 ： 土钉, 玻璃纤维复合材料（GFRP）, 双曲线关系, 拉拔试验, 抗剪强度
作者简介: 朱鸿鹄(1979– )，男，江苏苏州人，博士，副教授，主要从事岩土工程及光纤监测技术等方面的研究与教学工作。
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引用本文: 朱鸿鹄, 张诚成，裴华富，周游，施斌. GFRP土钉拉拔特性研究[J]. 岩土工程学报, 2012, 34(10): 1843-1849. ZHU Hong-hu, ZHANG Cheng-cheng, PEI Hua-fu, ZHOU You, SHI Bin. Pullout mechanism of GFRP soil nails. Chinese J. Geot. Eng., 2012, 34(10): 1843-1849.
Pullout mechanism of GFRP soil nails
ZHU Hong-hu1, 2, ZHANG Cheng-cheng1, PEI Hua-fu3, ZHOU You1, SHI Bin1
1. School of Earth Sciences and Engineering, Nanjing University, Nanjing 210093, China;
2. State Key Laboratory of Geohazard Prevention and Geoenvironment Protection, Chengdu University of Technology, Chengdu 610059, China;
3. Department of Civil and Structural Engineering, The Hong Kong Polytechnic University, Hong Kong, China
Abstract：Recently, great attention has been drawn to the new soil nail materials represented by glass fiber reinforced polymer (GFRP) as the traditional materials show certain disadvantages, including low corrosion resistance and poor durability. According to the loading characteristics of GFRP soil nails, a model using a hyperbolic shear stress-shear strain relationship is proposed to describe the pullout performance of GFRP soil nails during pullout. Numerical analysis is made to solve the pullout governing equation, based on which the distribution of axial force, shear stress and displacement along the nail length is calculated. Besides, laboratory pullout tests on a model soil nail are conducted, and the accuracy of the predicted results by the proposed model is verified by the test results. Furthermore, a parametric study of the pullout model is conducted to analyze the influence of nail diameter, shear resistance of soil-nail interface, and modulus ratio between soil and nail. Finally, the allowable pullout resistance of GFRP soil nails is suggested to be determined using the displacement control approach.
Key words： soil nail glass fiber reinforced polymer (GFRP) hyperbolic relationship pullout test shear resistance