【作者】 王浩；

【导师】 王海超；

【作者基本信息】 山东科技大学 ， 结构工程， 2020， 硕士

【摘要】 现阶段为了有效地改善混凝土柱的力学性能,通常采取各种措施,使混凝土处于三向受力状态,从而提高混凝土的强度和变形能力,已得到学术界的广泛认可。现如今,已初步形成了钢管约束混凝土柱、FRP约束混凝土柱和箍筋约束混凝土柱三大约束混凝土柱体系。对于箍筋约束混凝土柱的研究,主要考虑混凝土强度、配箍类型、箍筋强度和间距等影响箍筋约束效果的因素。本文分析了各配箍类型的约束机理,并将配置复合箍筋的试件和配置S-Clip加强筋的试件试验和数值模拟结果进行对比分析,验证了本文有限元分析方法的可行性和合理性。整理分析了配置S-Clip加强筋约束对钢筋混凝土试验柱抗震性能的影响,并在此基础上,通过ABAQUS有限元分析软件,进一步分析了在低轴压比下一种新型配箍类型即配置横向放置的S-Clip加强筋约束对钢筋混凝土柱抗震性能的影响,并和采用其他不同配箍类型(S-Clip加强筋、复合箍筋、S-Clip加强筋与交叉拉筋结合、横向S-Clip加强筋与交叉拉筋结合)的钢筋混凝土桥柱试件的抗震性能进行了对比分析,得出了各试件的应力云图、受压、受拉损伤云图、滞回曲线、骨架曲线、延性系数、刚度退化和耗能能力,表明了新型加强钢筋,即横向S-Clip加强筋对钢筋混凝土柱抗震性能的影响。通过对比观察发现,A、AS、B和BS的模拟曲线与试验曲线较符合,误差在15%以内。在相同纵向钢筋配筋率的条件下,配置横向S-Clip筋约束的试件滞回曲线面积最大,荷载降低速度最为缓慢,反映了刚度减小速度最慢。同时采用横放S-Clip加强筋约束的配箍方式使得试件具有更好的能量耗散能力。另外,试件的配筋率越高,极限荷载越大,试件刚度也越大。通过分析延性系数可知,在低轴压比下,AS’的延性系数比A高3.9%,BS’的延性系数比B高1.3%。因此与BS’对于B延性改善的效果相比,AS’对 A的延性改善效果更为明显。表明了在低轴压比下,AS’试件新型箍筋的配置方式最有利于改善钢筋混凝土桥柱的延性性能。最后,选择配置横向S-Clip加强筋的试件AS’作为研究对象,对其在不同轴压比作用下的滞回抗震性能进行了分析,得出了配置横向S-Clip加强筋试件的轴压比限值。在实际应用中,要合理限制轴压比,保证AS’柱的延性性能。更多还原

【Abstract】 At present,in order to effectively improve the mechanical properties of concrete columns,various measures are usually taken to make the concrete in a three-dimensional stress state,so as to improve the strength and deformation capacity of concrete,which has been widely recognized by the academic community.Now there are three kinds of confined concrete column systems:steel tube confined concrete column,FRP confined concrete column and stirrup confined concrete column.For the study of stirrup confined concrete columns,the main factors that affect the effect of stirrup are concrete strength,stirrup type,stirrup strength and spacing.In this paper,the restraint mechanism of each type of stirrup is analyzed,and the test and numerical simulation results of composite stirrup and S-Clip stiffener are compared to verify the feasibility and rationality of the finite element analysis method in this paper.Based on the analysis of the influence of S-Clip stiffener on the seismic performance of reinforced concrete test columns,under the low axial compression ratio,the influence of a new type of stirrup,i.e.S-Clip stiffener restraint placed transversely on the seismic performance of reinforced concrete columns,is further analyzed by using ABAQUS finite element analysis software,and compared with other types of stirrups(S-Clip stiffener,composite stirrup,combination of S-Clip reinforcement and cross tie,and combination of transverse S-Clip reinforcement and cross tie).And the stress nephogram,compression nephogram,tensile damage nephogram,hysteretic curve,skeleton curve,ductility coefficient,rigidity degradation and energy consumption capacity of each specimen are obtained,which show the influence of seismic performance of the new type of reinforcement,i.e.transverse S-Clip reinforcement on concrete columns.Through comparative observation,it is found that the simulation curves of A,AS,B and BS are in good agreement with the test curves,and the error is within 15%.The area of hysteretic curve of specimens restrained by transverse S-Clip reinforcement is the largest,and the speed of load reduction is the slowest,reflecting the slowest speed of stiffness reduction.At the same time,the stirrup with transverse S-Clip stiffeners makes the specimen have better energy dissipation capacity.In addition,the higher the reinforcement ratio,the greater the ultimate load and the greater the rigidity of the specimen.By analyzing the ductility coefficient,we can see that under the low axial compression ratio,the ductility coefficient of AS ’ is 3.9%higher than that of A,and the ductility coefficient of BS ’is 1.3%higher than that of B.Therefore,compared with the effect of BS’ on ductility improvement of B,AS’ has more obvious effect on ductility improvement of A.The results show that the new stirrup configuration of AS’ specimen is most beneficial to improve the ductility of reinforced concrete columns under the low axial compression ratio.Finally,AS’ with transverse S-Clip stiffeners is selected as the research object,and its hysteretic seismic performance under different axial compression ratio is analyzed,and the axial compression ratio limit value of transverse S-Clip stiffeners is obtained.In practical application,the axial compression ratio should be reasonably limited to ensure the ductility of AS ’ columns.更多还原