基于压力路径法钢筋混凝土梁的抗剪试验研究
发布时间：2018-12-06 16:44
【摘要】：钢筋混凝土梁的抗剪承载力研究是混凝土结构基本理论中的一个重要问题,各国学者对此问题做了广泛而深入的探索和试验研究。但是由于抗剪问题的影响因素众多且相互作用复杂,至今学术界尚未对剪切破坏机理得出一个统一的理论和计算模型。随着试验和理论的发展,提出的计算模型趋于合理,但包括我国规范在内的大部分国家的混凝土结构设计规范给出的受剪承载力计算公式仍是基于试验结果统计分析的具有一定保证率的半理论半经验公式。虽然我国现行规范公式的计算可靠度有了一定程度的提高,但箍筋用钢量比之前使用的规范计算值可能增加约25%。因此,我国规范需要一个更加合理有效的既可以保证承载力又能够合理配筋的新理论。压力路径理论认为,处于极限状态的钢筋混凝土梁对抗剪的主要受力区域位于压力路径上,这也导致该截面成为梁的危险截面,在这些位置加强箍筋配置可以提高梁的抗剪承载力。本文依据压力路径理论,设计了6组不同剪跨比的钢筋混凝土梁,每组2个试件,对比压力路径法配筋和我国现行规范方法配筋的效果。通过试验,分析极限荷载、试验梁的破坏过程和破坏模式、荷载-挠度曲线、荷载-应变曲线等力学性能。通过对压力路径法配筋梁的受剪机理的分析,验证压力路径法在实际应用中的有效性、安全性,研究不同剪跨比对压力路径配筋方法的影响,并与传统规范配筋梁的抗剪性能进行对比。试验结果表明:试件沿压力路径传递的应力是影响抗剪强度的主要因素,按照压力路径法配筋不但可以提高梁的抗剪强度,而且其配箍率也要低于我国传统方法。综合分析我国现行规范配筋方法的优缺点、实际应用中存在的不足和压力路径理论的适用性,提出安全性高、配筋合理的钢筋混凝土梁配筋计算方法及其受剪破坏机理,为我国钢筋混凝土梁的配筋计算方法研究和相关规范编制提供参考。
[Abstract]:The research of shear bearing capacity of reinforced concrete beams is an important problem in the basic theory of concrete structures. Scholars from all over the world have made extensive and in-depth exploration and experimental research on this problem. However, due to the large number of factors affecting shear failure and the complexity of interaction, the academic community has not yet come up with a unified theoretical and computational model for the shear failure mechanism. With the development of experiment and theory, the proposed calculation model tends to be reasonable. However, the calculation formula of shear capacity given by the code of concrete structure design in most countries, including the code of our country, is still a semi-theoretical and semi-empirical formula with certain guarantee rate based on the statistical analysis of test results. Although the calculation reliability of the current code formula in China has been improved to a certain extent, the amount of steel used for stirrups may increase by about 25% compared with the calculated value of the code used before. Therefore, China's code needs a more reasonable and effective new theory, which can guarantee both bearing capacity and reinforcement. According to the theory of pressure path, the main force area of reinforced concrete beam in ultimate state is located on the pressure path, which leads to the section becoming the dangerous section of the beam. Strengthening stirrups in these positions can improve the shear capacity of beams. Based on the theory of pressure path, six groups of reinforced concrete beams with different shear span ratios are designed. The ultimate load, failure process and failure mode, load-deflection curve, load-strain curve and so on are analyzed. Through the analysis of shear mechanism of reinforced beam with pressure path method, the effectiveness and safety of pressure path method in practical application are verified, and the influence of different shear span ratio on the reinforcement method of pressure path is studied. The shear behavior of reinforced beams is compared with that of traditional reinforced beams. The test results show that the stress transmitted by the specimen along the pressure path is the main factor affecting the shear strength. The reinforcement with the pressure path method can not only improve the shear strength of the beam, but also its hoop ratio is lower than that of the traditional method in China. Based on the comprehensive analysis of the advantages and disadvantages of the current code reinforcement methods in China, the shortcomings in practical application and the applicability of the pressure path theory, this paper puts forward the calculation method and shear failure mechanism of reinforced concrete beams with high safety and reasonable reinforcement. It provides a reference for the research of reinforcement calculation method and the compilation of relevant codes of reinforced concrete beams in China.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU375.1
本文编号：2366335
[Abstract]:The research of shear bearing capacity of reinforced concrete beams is an important problem in the basic theory of concrete structures. Scholars from all over the world have made extensive and in-depth exploration and experimental research on this problem. However, due to the large number of factors affecting shear failure and the complexity of interaction, the academic community has not yet come up with a unified theoretical and computational model for the shear failure mechanism. With the development of experiment and theory, the proposed calculation model tends to be reasonable. However, the calculation formula of shear capacity given by the code of concrete structure design in most countries, including the code of our country, is still a semi-theoretical and semi-empirical formula with certain guarantee rate based on the statistical analysis of test results. Although the calculation reliability of the current code formula in China has been improved to a certain extent, the amount of steel used for stirrups may increase by about 25% compared with the calculated value of the code used before. Therefore, China's code needs a more reasonable and effective new theory, which can guarantee both bearing capacity and reinforcement. According to the theory of pressure path, the main force area of reinforced concrete beam in ultimate state is located on the pressure path, which leads to the section becoming the dangerous section of the beam. Strengthening stirrups in these positions can improve the shear capacity of beams. Based on the theory of pressure path, six groups of reinforced concrete beams with different shear span ratios are designed. The ultimate load, failure process and failure mode, load-deflection curve, load-strain curve and so on are analyzed. Through the analysis of shear mechanism of reinforced beam with pressure path method, the effectiveness and safety of pressure path method in practical application are verified, and the influence of different shear span ratio on the reinforcement method of pressure path is studied. The shear behavior of reinforced beams is compared with that of traditional reinforced beams. The test results show that the stress transmitted by the specimen along the pressure path is the main factor affecting the shear strength. The reinforcement with the pressure path method can not only improve the shear strength of the beam, but also its hoop ratio is lower than that of the traditional method in China. Based on the comprehensive analysis of the advantages and disadvantages of the current code reinforcement methods in China, the shortcomings in practical application and the applicability of the pressure path theory, this paper puts forward the calculation method and shear failure mechanism of reinforced concrete beams with high safety and reasonable reinforcement. It provides a reference for the research of reinforcement calculation method and the compilation of relevant codes of reinforced concrete beams in China.
【学位授予单位】：长安大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TU375.1
【参考文献】
相关期刊论文 前5条
1 魏巍巍;贡金鑫;;基于修正压力场理论的有腹筋钢筋混凝土受弯构件受剪计算[J];建筑结构学报;2011年05期
2 邵永健,毛小勇;钢筋混凝土梁斜截面受剪承载力计算方法的改进[J];建筑结构;2003年08期
3 苏小卒,Ｄａｖｉｄ Ｈａｌｄａｎｃｅ,Ａｔａｌａｈ Ｓ Ｋｕｔａｂ;钢筋混凝土梁抗剪的一种机理[J];福州大学学报(自然科学版);1996年S1期
4 刘立新;钢筋混凝土深梁、短梁和浅梁受剪承载力的统一计算方法[J];建筑结构学报;1995年04期
5 刘立新，田秋;钢筋混凝土受剪构件和受扭构件的破坏机理及受力模型的探讨[J];郑州工学院学报;1994年04期
相关博士学位论文 前1条
1 魏巍巍;基于修正压力场理论的钢筋混凝土结构受剪承载力及变形研究[D];大连理工大学;2011年
相关硕士学位论文 前4条
1 王昱;骨料粒径对无腹筋梁抗剪性能影响的试验研究[D];湖南大学;2014年
2 王峥;钢筋混凝土梁斜截面受剪承载力研究[D];西安建筑科技大学;2012年
3 潘柏荣;高强混凝土梁抗剪性能试验研究[D];湖南大学;2009年
4 徐东坡;基于修正压力场理论的混凝土梁抗剪研究[D];大连理工大学;2006年
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