【作者】 黄明华；

【导师】 欧进萍； 周智；

【作者基本信息】 哈尔滨工业大学 ， 防灾减灾工程及防护工程， 2014， 博士

【摘要】 我国是世界上地质灾害最为严重的国家之一。锚杆支护技术具有充分调动岩土体强度、减轻结构物自重以及节约工程材料等优点，近年来已逐渐发展为地质灾害预防与治理的主要技术手段，在边坡、基坑以及隧道等岩土工程领域得到了广泛应用。但是，由于加固对象和工作环境的复杂性，至今锚杆支护原理仍没有形成一个统一和全面的认识，对于复杂条件下锚杆的应力分布与传递规律以及检测与监测技术等问题亟需更为深入的研究。本文采用理论分析、试验实测以及工程应用相结合的方法，围绕锚杆拉拔荷载传递与内嵌光纤传感的全尺度监测验证展开了较系统研究，主要内容包括：首先，考虑界面非线性特性，从锚杆荷载位移的指数曲线关系出发，建立了锚固界面的曲线剪切滑移模型；采用荷载传递函数法推导了张拉荷载作用下锚杆的荷载传递解析解，并通过室内和现场实测锚杆拉拔试验数据进行了验证，对锚杆拉拔受力特征进行了分析。其次，考虑界面残余剪切强度影响，进一步拓展了锚固界面的曲线剪切滑移模型，利用切比雪夫多项式推导了该模型下锚杆的荷载传递解析解，分析了不同残余剪切强度条件下锚杆的拉拔受力特征，并通过实测数据对模型和荷载传递解答进行了验证。第三，考虑岩土局部脱空不连续特征，结合上述建立的曲线剪切滑移模型及分析方法，构建了局部脱空岩土锚杆锚固段的拉拔荷载传递解答，对局部脱空岩土锚杆锚固段的拉拔荷载传递特征进行了探讨，分析了局部脱空参数对锚杆锚固段拉拔荷载传递特征的影响。最后，针对实际工程锚杆拉拔受力长期测试的全尺度监测需求，在阐述光纤传感技术原理的基础上，研制了系列内嵌光纤FRP智能锚杆，并对其制备工艺进行了探讨；基于研制的智能锚杆，对均质和局部脱空岩土锚杆的受力特征进行了拉拔试验研究，分析了上述工况智能锚杆的应力分布和界面损伤特征，探讨了智能锚杆对应力分布和界面损伤的全尺度监测性能，并对比分析了智能锚杆的全尺度监测与理论计算结果，验证了智能锚杆的全尺度监测性能和解析解的有效性。在此基础上，结合某边坡工程的实际监测需求，采用内嵌光纤FRP智能锚杆对边坡加固锚杆的应力状态进行了监测，获得了边坡锚杆的应力分布特征和演化规律，验证了智能锚杆在实际工程中应用的有效性和可靠性。更多还原

【Abstract】 China is one of the countries influenced by geological disasters most seriously. With the advantages of strengthening soil, lightening structure, saving material and shortening period, geotechnical anchor, which has been becoming the major technology to prevent and deal with geological disasters, has been widely applied in geotechnical engineering such as slope, foundation pit and tunnel in recent years. However, due to the complexity of surrounding soil and environment, the principles of geotechnical anchor have not yet common and completely understood. Thus geotechnical anchor need more study on the stress distribution and transfer mechanism as well as the detecting and monitoring technologies under complex soil and environment. This study has focused on the pullout load transfer mechanism of geotechnical anchor under tension as well as its full-scale monitoring technology and validation based on optical fiber sensors by means of theoretical analysis, experimental measurement and engineering practice. The content of this study mainly contains:Firstly, a novel curvilinear shear stress-slip model is developed from exponential load-displacement relationship curve in consideration of interfacial nonlinearity. Adopting load transfer function method, load-transfer solution of the anchor is derived, which is verified by measuring result from both laboratory and field tests subsequently. Based on this solution, the pullout mechanical behavior of the anchor is analysis.Secondly, the developed curvilinear shear stress-slip model is expanded in consideration of interfacial residual strength. Subsequently, load-transfer solution of the anchor under the expanded model is derived by means of Chebyshev polynomial approximation. Then measuring results are applied to verify this model as well as solution and the pullout mechanical behavior of the anchor with different residual shear strengths are discussed.Thirdly, adopting the above method and curvilinear shear stress-slip models, load-transfer solutions of the anchors in imperfect soils are derived expandly considering the imperfect characteristics. Then the pullout mechanical behavior of the anchors in imperfect soils is discussed as well as the influences from the imperfect parameters.Finally, aiming at the full-scale monitoring requirement of the anchorage engineering, series of smart FRP anchors with built-in optical fiber sensor are developed after discussing the sensing principle of optical fiber sensor. The fabricating processes of these smart anchors are also discussed. Adopting these smart anchors, experiments on pullout load transfer mechanism of the anchors in homogeneous and imperfect soils are carried out in laboratory. The stress distributed and interfacial damage characteristics of the anchors in above cases are studied in sequence to test the performance of the smart FRP anchor on monitoring stress distributed and interfacial damage characteristics. The results from full-scale monitoring and theoretical calculation are compared to verify the effectiveness of both smart FRP anchor and developed solutions. Then the smart anchors are applied in one slope project to verify the effectiveness and reliability. The stress distribution and long-term evolution of the slope anchors are monitored and discussed.更多还原