【作者】 邓艳青；

【导师】 韦锋； 白绍良；

【作者基本信息】 重庆大学 ， 结构工程， 2010， 硕士

【摘要】 当前我国建筑业对钢材的需求大,为了保持经济的可持续发展、节约资源利用,国家研制了HRB500高强钢筋。高强钢筋具有可以提高构件强度、减低用钢量以及减少构件截面尺寸等优点,但同时也具有极限变形大等弱点。再加上我国钢筋混凝土结构普遍使用的非预应力钢筋强度跟发达国家相比都要低,为了把HRB500钢筋纳入新的规范,推广HRB500钢筋在实际工程中的应用,很有必要对配置HRB500钢筋混凝土构件的受力性能进行检验。通过对各国规范中柱子箍筋加密区的构造对比,我国规范与国外规范在配箍特征值的取值上有较大差别,为此应对不同配箍特征值柱的抗震性能进行检验。此外,在钢筋混凝土柱中采用更高强度的HRB500钢筋后,按照我国现行规范设计的柱子其抗震性能能否达到要求也应进行验证。本文进行了4根配置HRB500纵筋柱的低周反复荷载试验,分析了配箍率、配箍特征值、箍筋强度以及配箍形式等因素对柱的破坏状态、P?△滞回曲线、延性、刚度退化以及耗能能力的影响;对比分析了条件基本相同情况下配置HRB500纵筋柱与配置HRB335纵筋柱受力性能的差异。试验分析结果表明:①与欧美国家的规范对比发现中国规范中柱子加密区配箍特征值限值普遍要小,且随轴压比的增大差值越大。②配箍特征值高的试件,其延性能力有明显的提高,承载力退化有较明显的改善,具有较好的抗震性能。③对于HRB500钢筋混凝土柱,在配箍特征值相当的条件下,采用复合配7箍的试件比普通配箍试件的延性有明显改善。④从现有两个试件的试验对比发现封闭“”字形复合箍筋与拉结筋“”字形复合箍筋二者在滞回曲线、滞回耗能以及刚度退化等抗震性能各方面差异并不明显。⑤在钢筋混凝土柱中采用HRB500级纵筋,对柱的位移延性系数有一定的影响,但是能够满足变形能力及位移延性的要求。更多还原

【Abstract】 Now there is great demand for steel construction industry, so in order to keep economic continued developing and save resources, The high-strength reinforced HRB500 is made. The high-strength reinforced have advantage of enforcing specimen’s strength, decreasing the amount of reinforced and reducing specimen’s sectional dimension and so on, but it also have some questions, for example,the ultimate deformation is large. Moreover the non-prestressed reinforced strength of reinforced concrete structure which used in general in China is relatively low compared with that of the developed countries. It is necessary to kown the mechanical behavior of reinforced concrete specimens with HRB500 reinforced for bringing it into specification and promoting its’application in the actural project.In the specifications on detailing of stirrups and Minimum Hoop Characteristic Factors in column hoop densified regions, there exists large difference between Chinese Codes and related codes of other countries. So it is necessary to check the seismic behaviors of columns with different transverse reinforcement schemes in different codes. Moreover, it is also needed to verify the seismic behaviors of columns, designed by Chinese Codes, using HRB500 bars with a higher strength as longitudinal reinforcements. Cyclic loading tests of 9 RC column specimens reinforced with HRB500 steel bar were conducted. The test parameters included the transverse reinforcement ratio, hoop characteristic value, stirrup strength and arrangement of stirrups. The effects of these parameters on the failure mechanism, load-deflection hysteretic-curve, ductility, stiffness degradation and energy-dissipating capacity are analyzed. Different behaviors between the columns with HRB500 bars and those with HRB335 bars are discussed, with other parameters remaining the same.Experimental results show that:①Compared with codes of other countries in the specifications on detailing of stirrups and Minimum Hoop Characteristic Factors in column hoop densified regions, the limit value of hoop characteristic value of Chinese codes is lower,especiclly when axial compression ratio is higher.②The specimens which have high reinfoceing steel indexes own higher ductility, improve its’capacity degradation apparently and have better seismic behaviors.③For HRB500 reinforced concrete column, the specimen with composite stirrups have better ductility compared with the specimen with ordinary stirrups when their reinfoceing steel indexes about the same.④Compared the specimen of“”shape closed composite stirrups with the specimen of“”shape composite stirrups with tie wire, we can find that there are not apparently difference in the factor of seismic behaviors which conclude hysteretic curve,hysteretic energy dissipation,stiffness degradation and so on.⑤Though the reinforced concrete columns with HRB500reinforced has influence on their ductility, it can satisfied the requirements of deformation and ductility. .更多还原