钢板混凝土连梁抗剪性能试验与设计方法

发布时间：2018-08-17 15:39

【摘要】：高层建筑结构中,连梁对剪力墙的承载力、刚度、延性等具有重要影响。利用连梁的延性与耗能能力,耗散地震能量,连梁是剪力墙结构实现二道设防设计的重要构件。在连梁两端作用有反向弯矩,连梁截面厚度较小,对剪切变形敏感、容易剪切破坏。通过在连梁中配置钢板,使钢板和钢筋混凝土共同参与抗剪,从而改善普通钢筋混凝土连梁的抗剪性能。完成了跨高比为1.5的12个不同配板率的钢板混凝土连梁试件的拟静力试验。试验结果表明,由于内置钢板的存在,钢板混凝土连梁的抗剪承载力、位移延性和耗能能力明显高于钢筋混凝土连梁。配置钢板后,连梁的承载力得到了明显提高,并且承载力随配板率的增大而提高,当配板率增大到一定程度时,承载力提高的不再明显,继续增大配板率承载力反而下降；钢板混凝土连梁试件的滞回曲线包围的面积明显大于普通混凝土连梁,说明前者耗能能力远大于后者,而且随着配板率的增大,滞回曲线包围的面积增大。连梁中配置钢板后耗能能力显著提高,强度和刚度退化较慢,具有较好的抗震耗能能力,但配板率对连梁的耗能影响不大。对试验量测结果进行了详细的应变分析和抗剪承载力分析。实测应变表明,试件屈服之前,连梁反弯点位于跨中附近,而且连梁截面上的正应变分布基本满足平截面假定；在试件屈服之后,连梁反弯点逐渐向受压区移动,钢板截面高度中间具有较大的正应变,说明试件屈服后,该处钢板具有较大的轴力,而钢板截面上下边缘正应变相对较小,因此,钢板参与部分抗弯,其抗弯承载力由两部分组成,一部分是钢板截面模量抵抗的弯矩,一部分是钢板的轴力对混凝土受压区合力点产生的力矩。对试件中钢板和箍筋各自承担的剪力进行了定量的分析,并且分析了配板率对钢板抗剪所做贡献的影响,分析结果表明,在试件屈服之前,主要由混凝土抗剪,钢板与箍筋的主要作用是约束裂缝的开展；试件屈服之后,混凝土开裂并逐渐退出抗剪工作,原来由混凝土承担的剪力转移给箍筋和钢板,当连梁中钢板的抗剪能力发挥到一定程度时,箍筋的抗剪作用相对减弱。基于此,提出了钢板混凝土连梁的抗剪承载力计算公式以及合理的配板率范围。利用ABAQUS有限元程序,对试验中的试件进行了非线性有限元分析,分析结果与试验基本符合。对不同配板率的钢板混凝土连梁试件进行有限元模拟,根据分析结果,验证了本文提出的抗剪承载力计算公式的正确性,提出了钢板混凝土连梁的设计建议,以期为工程设计提供参考。
[Abstract]:In high-rise buildings, connecting beams have an important influence on the bearing capacity, stiffness and ductility of shear walls. Using the ductility and energy dissipation capacity of the connecting beam and dissipating seismic energy, the connected beam is an important component of the shear wall structure to realize the design of the second channel fortification. There is reverse bending moment at both ends of the connecting beam, the thickness of the connecting beam section is small, it is sensitive to shear deformation and easy to shear failure. The shear resistance of ordinary reinforced concrete beams can be improved by placing steel plate in the connecting beam and making the steel plate and reinforced concrete participate in the shear resistance together. The pseudostatic tests of 12 steel plate concrete beams with different ratio of span to height of 1.5 were carried out. The test results show that the shear capacity, displacement ductility and energy dissipation capacity of steel plate concrete connecting beam are obviously higher than that of reinforced concrete connecting beam due to the existence of built-in steel plate. The bearing capacity of the steel plate is obviously increased, and the bearing capacity increases with the increase of the plate distribution ratio. When the plate ratio increases to a certain extent, the increase of the bearing capacity is no longer obvious, but the bearing capacity decreases with the increasing of the plate distribution ratio. The area surrounded by hysteretic curve of steel plate concrete connecting beam is obviously larger than that of ordinary concrete connecting beam, which shows that the former's energy dissipation ability is much larger than the latter, and the area surrounded by hysteretic curve increases with the increase of plate matching ratio. The energy dissipation capacity of the steel plate in the connecting beam is obviously increased, the degradation of strength and stiffness is slow, and the energy dissipation ability is better, but the ratio of plate matching has little effect on the energy dissipation of the connected beam. The test results are analyzed in detail by strain analysis and shear capacity analysis. The measured strain shows that the reverse bending point of the connecting beam is near the middle of the span before the specimen yielding, and the normal strain distribution on the section of the connecting beam basically meets the assumption of the plane section, and after the specimen yielding, the reverse bending point of the connected beam moves gradually to the compression zone. There is a large positive strain in the middle of the section height of the steel plate, which indicates that after the specimen yield, the steel plate has a larger axial force, while the positive strain of the upper and lower edge of the steel section is relatively small, so the steel plate takes part in the partial bending resistance. The flexural bearing capacity is composed of two parts, one is the bending moment of the steel plate section modulus resistance, the other is the moment caused by the axial force of the steel plate to the point of joint force in the concrete compression zone. The shear forces of steel plate and stirrups in the specimens are quantitatively analyzed, and the effect of plate ratio on the shear resistance of steel plate is analyzed. The results show that the shear resistance of concrete is the main factor before the specimen yield. The main function of steel plate and stirrups is to restrain the crack development; after the specimen yield, the concrete cracks and gradually withdraw from the shear work, the shear force originally carried by the concrete transferred to the stirrups and steel plates. When the shear resistance of steel plate in the beam reaches a certain extent, the shear resistance of stirrups is relatively weakened. Based on this, the formula of shear bearing capacity of steel plate concrete connecting beam and the reasonable range of plate ratio are put forward. The nonlinear finite element analysis of the specimen in the experiment is carried out by using the ABAQUS finite element program. The results of the analysis are in good agreement with the test results. The finite element simulation of steel plate concrete connecting beam specimens with different slabs ratio is carried out. According to the analysis results, the correctness of the formula of shear bearing capacity proposed in this paper is verified, and the design suggestion of steel plate concrete connecting beam is put forward. In order to provide reference for engineering design.
【学位授予单位】：沈阳建筑大学
【学位级别】：硕士
【学位授予年份】：2014
【分类号】：TU398.9

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