高温（火灾）下植筋式后锚固连接的抗剪机理研究

Although the post-installed adhesive connection has been accepted widely in retrofitting and reconstruction works, most existing research focused on its tensile resistance under high temperature, no available studies referring to its shear resistance can be found in literature.. Accordingly, this project will carry out a comprehensive experimental, numerical and analytical study on the shear resistance mechanism of the post-installed adhesive connection under high temperature due to fire. The post-installed adhesive connection with a single bolt will be investigated firstly. The relation between the failure mode, the loss in its shear capacity or deformability and the temperature will be investigated, and the influence of the embedment depth will also be observed. Then the effect of bolt group caused by different bolt spacing and edge distance on the shear performance will be studied as well. The performance of the bolted-side-plated RC beams with the post-installed adhesive connection will also be studied. The main achievements of this project will include the formulae used to compute the shear capacity and deformability of the post-installed adhesive connection under high temperature, and the simplified design method for the bolted-side-plated RC beams.. The outcome of this project will be the theoretical basis for the further research of the performance of post-installed adhesive connection under high temperature; it can also provide guideline for the strengthening design. Thus it is of great value for both scientific research and engineering practice.

虽然植筋式后锚固连接在加固和改造中已得到广泛应用，但对其抗高温性能的现有研究均侧重于考察抗拉拔性能，尚未见有对其抗剪性能的研究成果发表。.　　本项目旨在通过试验、数值仿真和理论分析相结合的方法，系统地研究高温（火灾）下植筋式后锚固连接的抗剪机理。以高温下植筋式单锚为研究起点，探讨其破坏形式、抗剪承载力及剪切变形能力损失与温度之间的关系，及其受植筋深度的影响；然后进一步考察植筋式群锚的抗剪性能受群锚效应的影响，即随不同锚栓间距和边距而改变的规律；此外还将研究高温下采用该连接技术的梁侧锚固钢板加固混凝土梁的受力性能。最后，本项目将提出高温下植筋式后锚固连接的抗剪承载力和变形能力计算公式，建立高温下梁侧锚固钢板加固梁的承载力计算方法。.　　本项目的成果可作为植筋式后锚固连接抗高温性能进一步研究的基础，也可作为植筋式后锚固连接加固设计的依据和参考，因而具有重要的科研意义和工程应用价值。

植筋式后锚固技术在对旧有建筑的加固和改造中的应用日趋广泛,但对于其高温性能的研究较多地侧重于抗拉拔性能，缺乏对于其抗剪性能的研究。为了探究高温对于植筋式后锚固连接性能的影响，分别进行了单锚和群锚的高温剪切试验，得到了其抗剪性能随温度、边距、埋深和间距等因素变化的规律。.在植筋式后锚固技术研究的基础上，对梁侧锚固钢板法加固混凝土梁的抗弯性能进行了试验研究、数值模拟和理论分析。.针对梁侧锚固钢板加固混凝土梁的抗弯性能进行了高温后的试验研究。由于国内关于在加劲措施下梁侧锚固钢板的受压屈曲特性以及钢筋混凝土梁抗弯性能的研究工作还没有相关的文献报道，所以常温下试验主要研究加劲措施对BSP法加固混凝土梁抗弯性能的影响。为研究梁侧锚固钢板加固火灾后受损混凝土梁的受弯性能，设计6个混凝土梁试件，预先按照ISO834国际标准升温曲线对其进行受火试验，然后采用梁侧锚固钢板加固其中5根受损梁，并对所有试件进行静力试验。分析了螺栓间距、角钢、梁侧钢板高度与厚度等因素对加固梁受弯承载力、刚度及耗能能力的影响。 .通过以上的试验研究，数值模拟及理论推导，最终本课题建立了一套BSP梁受弯加固设计的计算方法，对BSP法在实际工程中的应用具有良好的指导意义。