【作者】 张向冈；

【导师】 薛建阳； 陈宗平；

【作者基本信息】 广西大学 ， 结构工程， 2014， 博士

【摘要】 钢管再生混凝土结构是钢管普通混凝土结构和再生混凝土结构相结合而产生的一种新型结构体系,它不仅继承了钢管普通混凝土结构的承载力高、抗震性能好等优点,而且有效地解决了建筑垃圾的资源化再利用问题。课题组已对钢管再生混凝土构件的基本受压性能进行了研究,在此基础上本文对钢管再生混凝土构件及其框架的抗震性能进行了深入、系统的研究。以再生粗骨料取代率、长细比、轴压比和含钢率为变化参数,进行了低周反复荷载作用下10个圆形和6个方形钢管再生混凝土柱试件的抗震试验。观察了试件受力的全过程和破坏形态,获取了滞回曲线、骨架曲线、延性、耗能、强度衰减和刚度退化等各项抗震性能指标。结果表明：试件的滞回曲线饱满；圆形试件的位移延性系数大于3,方形试件接近3；圆形试件破坏时位移转角介于1/28～1/17之间,方形试件介于1/21～1/17之间；破坏时圆形试件的等效粘滞阻尼系数介于0.305～0.460之间；方形试件介于0.323～0.360之间；基于抗震性能指标需求,再生混凝土用于钢管混凝土工程承重结构之中是可行的。以100%为再生粗骨料取代率,进行了低周反复荷载作用下一榀圆钢管再生混凝土柱-钢筋再生混凝土梁和一榀方钢管再生混凝土柱-钢筋再生混凝土梁框架试件的抗震试验。结果表明：框架在设计方法上满足了“强柱弱梁、强剪弱弯、强节点,弱构件”等抗震设计要求；框架滞回曲线对称,呈现出比较饱满的梭形；框架位移延性系数均大于3；圆形试件破坏位移转角为1/33,方形试件为1/24；破坏时圆形试件等效粘滞阻尼系数为0.243,方形试件为0.216。钢管再生混凝土柱-钢筋再生混凝土梁框架表现出了良好的抗震性能。根据等效塑性铰理论,计算得到的圆形钢管再生混凝土柱试件的塑性铰长度介于(0.45～0.95)h之间,方形试件介于(0.65～0.75)h之间；通过采用定点指向、位移幅值承载力突降、模型软化点等特殊处理方法,建立了低周反复荷载作用下钢管再生混凝土构件的三折线恢复力模型,较好地反映了构件荷载与位移的滞回关系；通过引入多种地震损伤评估模型,全方位的评价了钢管再生混凝土构件损伤发展过程和抗震能力。考虑了取代率影响因子,修正了现有的核心混凝土的受压本构关系,并采用有限元软件Abaqus对钢管再生混凝土构件进行抗震性能分析,计算得到的滞回曲线与实测结果吻合较好。在现有有限元模型的基础之上,进行了抗震性能拓展分析,得到了不同单参数变化试件的抗震性能指标,探讨了再生粗骨料取代率、含钢率、钢材牌号、轴压比、长细比以及截面高宽比对抗震性能指标的影响规律。根据实测滞回曲线、骨架曲线以及刚度退化规律,建立了低周反复荷载作用下钢管再生混凝土框架的三折线恢复力模型,较好地反映了框架荷载与位移的滞回关系；基于试验结果,探讨了单层单跨钢管再生混凝土框架的层间受剪承载力的设计计算方法；通过引入基于变形和累积耗能控制的双参数地震损伤模型,有效的评价了钢管再生混凝士框架损伤发展过程和抗震能力；基于性能设计,划分钢管再生混凝土结构的性能水准为正常使用、暂时使用、修复后使用、生命安全和防止倒塌五档,选用水平位移角和损伤变量作为量化指标,确定了基于一定保证率下的水平位移角和损伤指标限值,建立了在不同地震设防水准下不同性能水准所对应的性能目标。更多还原

【Abstract】 Recycled aggregate concrete filled steel tube(RACFST) structure is a new system for the combination of concrete filled steel tube structure and recycled aggregate concrete(RAC) structure. It not only inherits the advantages of concrete filled steel tube structure, such as high bearing capacity, good seismic performance and so on, but also solves the resource recycling problem of construction waste effectively. Research group has carried out research about the basic compression behavior of RACFST component. Based on such research, in-depth and systematic study about seismic behavior of RACFST component and frame structure was carried out in this paper.Under the cyclic reversed loading, ten circular specimens and six square specimens were tested. Replacement rate, recycled coarse aggregate, slenderness rate, axial compression rate and steel rate were taken as design parameters. The entire loading process and failure mode were observed, the seismic behavior indexes including hysteretic curve, skeleton curve, ductility, dissipation capacity, strength attenuation and stiffness degeneration were obtained. It is shown that the hysteretic curves are plump; The displacement ductility factors of circular specimens are more than three, and ones of square specimens are closed to three; The displacement angle of circular specimens at failure point are between1/28 and1/17, ones of square circular specimens are between1/21and1/17; The equivalent viscous damping coefficients of circular specimens at failure point are between0.305and0.460, ones of square circular specimens are between0.323and0.360; Based on the seismic behavior indexes, RAC could be used to engineering capacity-bearing structure of concrete filled steel tube.With replacement rate of100%, RAC filled circular steel tube column versus reinforced RAC beam frame and RAC filled square steel tube column versus reinforced RAC beam frame were tested under the cyclic reversed loading. It is shown that the design methods of strong column and weak beam, strong shear capacity and weak bending capacity, strong node and the weak components are met; The hysteretic curve like a full fusiform is symmetrical; The displacement ductility factors are all more than three; The displacement angle of circular specimen at failure point is1/33, and one of square specimen is1/24; The equivalent viscous damping coefficient of circular specimen at failure point is0.243, and one of square specimen is0.216. The frame of RACFST column versus reinforced RAC beam shows excellent seismic behavior.Based on the theory of equivalent plastic hinge, the calculated plastic hinge length of circular specimens are between0.45h and0.95h, and ones of square specimens are between0.65h and0.75h; According to special method including fixed point, dropped bearing capacity of displacement amplitude and model softening point, restoring force model of a trilinear model was established for RACFST component under cyclic reversed loading, such model expressed well the hysteretic relation between load and displacement; Damage development process and seismic capacity of RACFST component was evaluated comprehensively by various earthquake damage models.The present relation between compressive stress and strain was revised by factor of replacement rate, the seismic behavior of RACFST component was analyzed by Abaqus, and the calculated hysteretic curve agreed well with the measured hysteretic curve. Based on existing finite element model, expanded analysis of seismic behavior was carried out, the seismic behavior indexes of one-parameter specimens were obtained, the influence rule replacement rate of recycled aggregate coarse, steel rate, steel type, axial compression rate and slenderness rate made on the seismic behavior indexes was discussed.According to measured hysteretic curve, skeleton curve and stiffness degradation rule, restoring force model of a trilinear model was established for RACFST frame structure under cyclic reversed loading; such model expressed well the hysteretic relation between load and displacement; Based on test result, the one-story, one-bay RACFST frame calculation method about the shear bearing capacity between the layers was discussed; Damage development process and seismic capacity of RACFST frame structure was evaluated effectively by double parameters including deformation and accumulated energy dissipation earthquake damage models. Based on performance design, performance level of RACFST structure was divided into normal use, temporary use, use after repair, life safety and collapse prevention, displacement angle and damage index were taken as quantitative index for performance level, and based on the considerable probability, the limit of the displacement angle and damage index were determined, performance goals were established under different performance levels and different seismic fortification levels.更多还原