【作者】 张沛；

【导师】 潘景龙；

【作者基本信息】 哈尔滨工业大学 ， 结构工程， 2007， 硕士

【摘要】 既有钢筋混凝土柱后接梁是在原有柱侧后接梁的加固改造方法,一般是通过植筋技术在柱侧植筋后再接梁,希望梁柱接头能够成为刚性节点。为保证梁端剪力有效的传递,梁柱接头会采用不同的连接方式。但后接梁柱接头往往会成为结构的最薄弱环节,接头连接的好坏,将影响着结构的抗震性、整体性和稳定性。目前,对于既有钢筋混凝土柱后接梁接头的连接型式、受力性能特点及承载力计算方法研究的较少,因此设计时缺乏足够的理论基础。鉴于此,本文通过对齿槽式、外贴钢板齿槽式和无齿直缝后植弯起钢筋式三种不同柱后接梁接头型式共9个足尺试件的静力试验,研究了在不同剪跨比作用下三种型式接头的受力性能和变形特点,并将同一剪跨下不同型式接头以及不同剪跨下相同型式接头的受力性能进行了对比分析。对于齿槽式接头,当剪跨比λ< 0.5时,齿槽剪切破坏,齿槽截面是控制截面;当剪跨比λ≥0.5时,后接梁发生剪弯破坏,齿槽截面并不起主要控制作用,还取决于后接梁的强度。外贴钢板齿槽式接头在剪跨比λ≥0.5时,后接梁剪弯破坏,钢板未发生剪切滑移,接头承载力取决于后接梁的强度。对于无齿直缝植弯起钢筋式接头,当剪跨比λ≥0.5时,首先发生整浇梁的剪弯破坏,此时后接梁表现出剪弯的受力特征,接头截面不起主要控制作用。试验结果表明,无齿直缝植弯起钢筋式接头具有较高的抗剪承载力,且接头的整体性较好,刚性较高,可以达到整浇节点的抗剪水平。结合接头抗剪承载力实测结果,建立各种型式接头的抗剪承载力计算公式,且所提建议公式与试验结果吻合较好,从而能为实际工程中柱后接梁加固设计提供一些理论依据和实际参考。更多还原

【Abstract】 Post-casted beam connected on existing reinforced concrete column is a method of strengthening and rebuilding, it casts the beam onto the side of column through the technique of inserting reinforced bars, it is hoped that the joint of beam-column will be rigid. In order to transfer the shear of beam efficiently, different kinds of connections can be used in the joint of beam-column. But the joint of beam-column is always the weakest part of the structure, so the connections of beam-column will impact the seismic behavior, monolithic and stability of the whole structure.At present, the researches on the connections of beam-column, mechanics characteristic and the methods of shear calculation are few, so the theories for engineering design are scarce. Therefore, a total of 9 tests were conducted on three kinds of full scale beam-column connections, including tooth-grooved connection, sticking steel plate welded angle iron connection and roughened interface with inserting bent-up bars connection. Studied the mechanics behavior and deformation characteristic of the three kinds of connections at different shear-span ratios, compared the behavior of different connections at the same shear-span ratio, and the behavior of the same connection at different shear-span ratios.For the tooth-grooved connection, when the shear-span ratioλ< 0.5, it happens shear failure of the tooth-groove, the section of tooth-groove is the dominance section; when the shear-span ratioλ≥0.5, it happens shear-flexural failure of the post-casted beam, the section of tooth-groove is not only the dominating factor, it also depends on the strength of post-casted beam. For the sticking steel plate welded angle iron connection, when the shear-span ratioλ≥0.5, it happens shear-flexural failure of the post-casted beam, there is no shear slippage between steel plate and column, the shear capacity of connection lies on the strength of post-casted beam.For the roughened interface with inserting bent-up bars connection, when the shear-span ratioλ≥0.5, the monolithic beam shows shear-flexural failure, and the post-casted beam shows shear-flexural behavior. The section of connection can not mainly determine its shear capacity.The test results indicates that the roughened interface with inserting bent-up bars connection has higher shear capacity, and it shows better monolithic and higher rigidity, so this kind of connection has the same behavior as the monolithic joint.According to the test results, the formula used to calculate the shear capacity of connections are proposed in this paper, it is shown that the theoretical values are in good agreement with that of the test one, and it can be used as reference in engineering practice.更多还原