预应力锚固研究与工程应用

发布时间：2018-01-09 01:16

本文关键词：预应力锚固研究与工程应用　出处：《中国水利水电科学研究院》2013年博士论文　论文类型：学位论文

【摘要】：随着我国经济建设的快速发展,城市化进程的不断加快,我国的基础设施建设正处于一个蓬勃发展的时期,在诸如水电、交通、能源等各种基础设施建设中产生了大量的高边坡和基坑工程。预应力锚索锚固系统能够有效的激发岩土体潜在承载能力,充分发挥岩土体自身强度,提高岩土体的自身稳定性,且其施工工程量小、安全性高、工期快、消耗小,具有极高的投入产出比。该锚固技术自诞生以来就颇受工程设计者及施工人员的青睐,在诸如水利、公路、铁路等各种工程的滑坡治理、高边坡支护工程中广泛应用。本文针对预应力锚索的荷载传递机理、预应力锚索的应力亏损机理及预应力锚索长期性能进行系统研究。结合实际高边坡预应力锚索加固工程提出边坡变形机制分析方法及边坡稳定性分析方法,并基于发明专利“压力分散型锚索的内锚固承载体”进行预应力锚索的设计,同时对预应力锚索施工过程进行探讨研究。在预应力锚索监测方面,文章分析了基十磁通量传感器的检测系统,并主要对光纤光栅的检测手段进行研究。本文具体研究内容包括以下几个方面： (1)对预应力锚索锚固段荷载传递解析进行探索,基于弹性力学凯尔文(kelvin)问题弹性解推导预应力锚索内锚固段应力分布弹性解。根据压力型锚索的主要失效模式从理论上分析了压力型锚索荷载传递机制。在考虑灌浆体三向受力状态的前提下,选择合适的荷载传递模型建立反映压力型锚索灌浆体与岩体粘接界面相互作用规律的基本方程,求解界面剪应力分布规律以及灌浆体中轴向应力应变分布规律。同时,分析了不同岩体、锚固体材料参数对应力分布的影响。理论上解释了压力型预应力锚索的荷载传递特点及主要影响因素。基于明德林解,采用积分法分析压力型岩锚锚固段周围岩体中的应力分布情况 (2)从预应力锚索锚固材料性质、被锚固介质力学性质、施工工艺及运行管理水平等多方面对预应力锚索预应力亏损进行分析研究。对锚墩基础沉降量引起的预应力亏损进行研究,考虑了预应力锚墩下土体在三向应力作用下的变形影响,引入土体弹塑性本构关系来阐述土体的变形特性,进而研究锚墩基础沉降引起的锚索预应力亏损。 (3)针对预应力锚索锚固的预应力亏损,讨论预应力锚索长期性能的综合控制措施,为工程设计及施工提供一定的参考依据。 (4)结合实际工程,对高边坡进行预应力锚固设计,在地质分析的基础上,选择典型剖面计算不同工作状态下的应力、应变,总结出边坡破坏模式,利用反演法推导力学参数计算边坡稳定加固荷载。基于发明专利“压力分散型锚索的内锚固承载体”进行预应力锚索的设计,同时对预应力锚索施工技术要领进行分析研究。 (5)对预应力锚索的监测进行研究,包括监测内容、项目、监测的基本要求等方面,研究基于磁通量的预应力锚索监测系统,主要对光纤光栅的检测手段进行研究,改进现有预应力锚索钢绞线形成基于光纤光栅传感器的智能钢绞线,对智能钢绞线的应力传感性能、温度传感性能等方面进行试验,证明智能钢绞线完全能满足用于拉索测量的基本条件。
[Abstract]:With the rapid development of China's economic construction, city urbanization process accelerating, the infrastructure construction of our country is in a period of vigorous development, such as hydropower, traffic, a large number of high slope and foundation pit engineering to produce energy and other infrastructure construction. The pre stress anchorage system can stimulate the potential bearing the ability of rock and soil effectively, give full play to the strength of rock and soil, improve soil stability, and the construction quantity is small, high safety, short construction period, low consumption and high input-output ratio. The anchoring technology since the birth of popular engineering designers and construction personnel in favor of highway such as water conservancy, landslide, railway engineering, application of high slope supporting engineering.
In this paper, according to the load transfer mechanism of prestressed anchor cable system, research the long-term performance of power loss mechanism and prestressed anchor for prestressed anchor cable. Combined with the actual high prestressed anchor cable in slope engineering is proposed analysis method of slope deformation mechanism and slope stability analysis method, and based on the design of a patented invention of pressure dispersion type anchorage cable internal anchoring bearing carrier of prestressed anchor cable at the same time, to study the construction process of prestressed anchor cable in prestressed anchor cable monitoring, this paper analyzes the detecting system based on ten magnetic flux sensor, and the main detection methods of fiber grating are studied.
The specific research contents of this paper include the following aspects:
(1) on the anchorage load transfer analysis to explore the elastic Kelvin (Kelvin) is based on the prestressed anchor within the anchorage section stress distribution of elastic solution of elastic solution. According to the main failure mode of the pressure type cable from the theoretical analysis of the pressure type cable load transfer mechanism. Considering the grouting condition to three the stress state of the transfer, basic equation model can reflect the law of pressure type anchor grouting and rock bonding interface interaction by selecting the appropriate load, solving the interfacial shear axial force distribution and grouting in stress and strain distributions. At the same time, analyzes the influence of different rock mass, anchor solid material parameters on the stress distribution. The theory explains the characteristics and main influencing factors of load transfer pressure type prestressed anchor. Based on Mindlin solution, using integral method around the analysis of compression rock anchor anchorage Stress distribution in rock mass
(2) from the properties of the prestressed anchorage materials, anchored medium mechanical properties analysis of prestressed anchor cable prestress loss on construction technology and operation management level. To study the loss caused by prestressed anchor pier foundation settlement, considering the prestressed anchor pier in soil under three to be deformation under the action of stress the deformation characteristics, the elastoplastic constitutive relationship of soil, and study the anchor pier prestress loss caused by foundation settlement.
(3) in view of the prestress loss of prestressed anchor cable, the comprehensive control measures for long-term performance of prestressed anchor cable are discussed, which will provide some reference for engineering design and construction.
(4) combined with the actual engineering, prestressed anchor design of high slope, on the basis of geological analysis, selecting typical sections are calculated in different working condition of stress, strain, summed up the failure mode of the slope, calculation of slope reinforcement load using the inversion method is designed. The mechanical parameters of prestressed anchor cable in Anchorage "invention patent pressure dispersion type anchorage cable carrier" based on the analysis and research of prestressed anchor cable construction technology essentials.
(5) study on monitoring of prestressed anchor rope, including monitoring content, monitoring project, the basic requirements, the research of prestressed anchor cable monitoring system based on the magnetic flux, the fiber grating detection method research, improvement of existing prestressed anchor cable steel strand formed intelligent steel strand based on fiber grating sensor, the intelligent steel strand the stress sensing properties, temperature sensing performance and other aspects of the test, that smart steel strand can meet the basic conditions for the measurement of the cable.

【学位授予单位】：中国水利水电科学研究院
【学位级别】：博士
【学位授予年份】：2013
【分类号】：TU476

【参考文献】