【作者】 车承志；

【导师】 易志坚；

【作者基本信息】 重庆交通学院 ， 工程力学， 2005， 硕士

【摘要】 本文简要总结了传统钢筋混凝土结构的优缺点,介绍了FRP片材应用于钢筋混凝土结构的发展历史和研究现状。在课题组前期研究的基础上,本文基于断裂力学基本原理归纳了GFRP复合钢筋混凝土梁用到的三个力学机理,并对新结构的界面问题进行了简单分析。应用有限元方法建立复合钢筋混凝土新结构的简化模型,为复合梁提供了一个新的分析方法。本文为了更深入了解复合钢筋混凝土新结构的力学性能,开拓工程应用的前景,对尺寸为(4000mm×180mm×450mm)的复合钢筋混凝土新结构构件进行了抗弯试验,进一步验证复合钢筋混凝土新结构的优良的力学性能,并在此基础上对“放”与“阻”相结合结构设计思想进行试验研究。实验结果表明:复合钢筋混凝土新结构能够发挥各种材料的各自特点,承载力较普通钢筋混凝土受弯构件大大提高,使受弯构件中的裂缝得到了极大改善,开裂后的刚度显著改善。对“放”与“阻”相结合的结构设计思想进行试验研究,研究结果表明:新结构的极限承载力提高;新结构的刚度增大,由于采取了裂缝封闭技术,其整体刚度将得到提高,从而提高在挠度控制标准下的使用性能;新结构的抗裂性能提高,表现为同等荷载水平下的裂纹宽度要小;新结构的老裂纹在裂纹封闭后,基本不发展。并推导了体现“放”与“阻”相结合结构设计思想的新结构的极限承载能力计算公式。本文得到国家自然科学基金项目“基于断裂力学原理的钢筋混凝土复合新结构设计理论研究”和重庆市教委科技项目“基于破坏力学原理的桥梁损伤机理与维护加固技术”的资助。更多还原

【Abstract】 In the paper the advantages and disadvantages of traditional reinforced concrete (RC) structures are summarized in brief, and the developing history and research status of application of FRP material to RC structures introduced.Based on the previous achievements of the research team, three mechanical mechanisms are generalized for the GFRP composite RC beams according to the fracture mechanics in the paper, and the interface problem of the new structure preliminarily analyzed. The simplified model for the new composite RC beam was built with finite elements to provide a new analytical approach. To further explore the mechanical behavior of the new composite RC beam and promote its future engineering application, a number of specimen beams of big dimensions (4000mm×180mm×450mm) have been tested in flexure, the excellent mechanical properties of the new beam verified and the design idea combining‘release’with‘prevent’checked. The experimental results indicate that, in the new composite RC beam the advantages of each material can be fully exploited to give much higher bearing capacity than common RC beams, at the same time the crack distribution as well as the post-cracking rigidity of the new beam greatly improved. The experimental research of the structure design idea combining‘release’with‘prevent’proved the remarkable increase of the new beam’s ultimate bearing capacity, the improvement of the new beam’s post-cracking rigidity and anti-deflection properties due to closure of the cracks, and the enhancement of anti-crack performance which is shown by the smaller crack widths under the same load levels and the tiny development of the cracks after they have been closed at their lower openings. In addition, the calculating formula of the ultimate bearing capacity for the new beam with the design idea combining‘release’with‘prevent’is deduced in the paper.更多还原