腹板开大洞口RC梁外贴CFRP和钢板加固性能研究

发布时间：2018-07-04 08:47

本文选题：碳纤维布 + 钢板　；参考：《烟台大学》2017年硕士论文

【摘要】：对房屋进行管道安装改造时,为了不影响层高需要在梁的腹板上开较大的洞口,以满足多管或大口径管道穿过的需求,具有良好的综合经济效益。然而在腹板上开洞会严重削弱梁的抗剪承载力,因此必须对开洞梁采取一定的加固措施来提高梁的整体受力性能。展开对开大洞口钢筋混凝土梁的加固研究,找到合理高效的开洞加固形式,为工程的实际应用提供可靠的理论基础,具有非常重要的意义。本文通过对3组试件进行弯曲试验,探讨了在不同孔洞参数和加固形式下RC开洞梁的裂缝开展破坏情况,并进行了受力性能的对比分析。试验分析结果表明:分别粘贴碳纤维布和钢板对开洞梁加固,都有效地约束了裂缝的开展,使开洞梁的抗剪承载力得到显著提高。二者对承载能力的提高幅度相差不大,采用碳纤维布加固相对偏高。就施工工艺而言,采用碳纤维布加固更为简便经济,但钢板加固对梁刚度增强较为显著。洞口大小的变化对开洞梁的加固效果具有较大的影响,会使加固梁最终发生不同的破坏形态。此外,加固材料与混凝土之间的粘结作用也是影响开洞梁加固的效果一个重要因素。在试验的基础上,采用TNO DIANA软件建立有限元模型对腹板开洞钢筋混凝土梁进行研究,利用试验结果对有限元模型进行了有效性检验和参数校正。通过分别对碳纤维布和钢板加固的开洞梁孔洞参数(包括开洞高度、开洞长度等)的设置分析,探讨了孔洞参数的改变对开洞加固梁受力性能的影响。结果表明:碳纤维布和钢板对开洞RC梁的加固效果都非常明显,但开洞不易过大,过长或过高都会对加固效果产生很大的影响,开洞高度相比开洞长度对加固梁的抗剪承载能力和剪切刚度的影响更大。本文基于试验结果与有限元参数分析,对分别采用碳纤维布和钢板加固的较大洞口的开洞梁的抗剪性能进行了深入研究,探索了不同开洞参数对加固效果的影响,为腹板开洞RC梁加固的实际工程应用提供了可靠的理论基础。
[Abstract]:In order to avoid the influence of floor height on the installation and reconstruction of the building, a large opening should be opened on the web of the beam to meet the needs of multi-pipe or large-caliber pipeline, which has good comprehensive economic benefits. However, opening a hole in the web will seriously weaken the shear capacity of the beam, so it is necessary to take some reinforcement measures to improve the overall mechanical performance of the beam. It is of great significance to study the reinforcement of reinforced concrete beams with large openings and find a reasonable and efficient reinforcement form for the practical application of the project. Based on the bending tests of three groups of specimens, the fracture failure of RC beams with open holes under different hole parameters and reinforcement forms is discussed, and the mechanical properties of RC beams are compared and analyzed. The experimental results show that the crack development is restrained effectively and the shear bearing capacity of the open beam is improved significantly by bonding carbon fiber sheet and steel plate respectively to strengthen the open hole beam. The increase of bearing capacity is not different between them, and the reinforcement of CFRP is relatively high. In terms of construction technology, it is more convenient and economical to reinforce with carbon fiber sheet, but the rigidity of beam strengthened by steel plate is obvious. The change of the hole size has a great influence on the reinforcement effect of the beam, which will lead to different failure patterns of the strengthened beam. In addition, the bond between reinforcement material and concrete is also an important factor affecting the reinforcement effect of open beam. On the basis of the experiment, the finite element model of the web opening reinforced concrete beam is established by TNO Diana software. The validity of the finite element model and the parameter correction are verified by the test results. Through setting and analyzing the hole parameters (including the height and length of the hole) of the beam strengthened with carbon fiber sheet and steel plate respectively, the influence of the change of the hole parameters on the mechanical performance of the beam strengthened with the hole is discussed. The results show that the reinforcement effect of carbon fiber sheet and steel plate is very obvious, but the hole opening is not easy to be too large, too long or too high will have a great effect on the reinforcement effect. The height of the hole has more influence on the shear bearing capacity and shear stiffness of the strengthened beam than the length of the hole. Based on the experimental results and finite element parameter analysis, the shear behavior of large hole beam strengthened with carbon fiber sheet and steel plate is studied in this paper, and the influence of different hole opening parameters on the reinforcement effect is explored. It provides a reliable theoretical basis for the practical engineering application of RC beams strengthened with web openings.
【学位授予单位】：烟台大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU375.1

【参考文献】