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贮液结构是一种极为重要的构筑物,与人民群众日常生产和生活息息相关。随着贮液不同,贮液结构广泛应用于生命线工程和能源与化工领域,如水塔、水箱、储油罐、储酸罐、消化池、降温池、冷凝器等,其结构形式也多种多样,包括半地下式、立式、卧式、支承式等。由于存在液固耦合作用,这种结构动力响应极为复杂,尤其是强地震动作用下,引起的震害现象千差万别。历次震害表明,高烈度区大量贮液结构受到破坏,如浮放支座移位、支 相似文献
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储液池的抗震问题探讨 总被引：1，自引：0，他引：1
应用流体固体动力耦合统一分析模型的有限元法，进行了储液池的抗震分析。分别探讨了储液池内液体的液面大幅波动、池壁刚度变化、池的深宽比等对地震响应的影响。研究结果表明：储液池壁刚度是比较敏感的物理量，弹性比刚性池壁与液体相互作用的非线性行为强，池壁所受流体的作用力大；液面波的影响也有同样规律，刚性池壁情况下考虑面波与否影响不太大，但弹性池壁却有较大影响；另外宽池比窄池的响应强。 相似文献
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本文考虑液固耦联及底板几何非线性与土壤弹性，建立了液－固－土耦合的储液罐翘离分析力学模型。算例表明，恢复力矩与翘离角之间的关系可以表达为分段线性，翘离将使地震响应增大。 相似文献
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15×104m3储罐的动特性分析 总被引：3，自引：1，他引：2
立式钢制圆柱形储罐向着大型化和浮放式发展,其动力特性参数,如结构的固有频率和固有振型,在地震工程中经常被使用,以15×104m3储罐为例,应用ADINA有限元程序,采用弹簧单元来模拟地基,考虑液固耦合效应对其进行了模态分析.结果表明:采用弹簧单元来模拟地基进行储罐的分析时,有限元与规范近似算法比较接近;15×104m3储罐液固耦合振动低频的振动形式比较丰富,以 cosnθ、sinnθ型梁式振动为主,液体晃动低频的振动形式比较单一,即cosnθ、sinnθ型梁式振动;液固耦合振动频率对地基刚度最为敏感,储液高度与储罐高径比次之,受罐壁厚度的影响比较小;液体晃动频率对罐壁厚度和地基刚度不敏感,对储液高度与高径比则比较敏感. 相似文献
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为研究不同贮料状态下钢筋混凝土柱承式立筒群仓结构的动力特性及其在地震作用下的动力响应规律,对缩尺比例为1:25的3×3组合柱承式立筒群仓结构模型进行了振动台试验。试验结果表明:柱承式筒仓结构具有“上刚下柔”的特性,使其加速度响应和整体变形均沿高度呈折线型,折点在刚度突变的柱顶和仓壁连接部位;贮料状态对立筒群仓结构动力特性的影响较大,随着贮料质量的增加,群仓模型加速度响应、位移响应的弯折效应均更加明显,边仓和角仓的加速度响应均逐渐增大;贮料及其与仓体间相互作用对耗能的贡献随着台面加载等级的增加而逐渐加大。 相似文献
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立式钢制圆柱形储罐向着大型化和浮放式发展,其动力特性参数,如结构的固有频率和固有振型,在地震工程中经常被使用,以15×104m3储罐为例,应用ADINA有限元程序,采用弹簧单元来模拟地基,考虑液固耦合效应对其进行了模态分析。结果表明:采用弹簧单元来模拟地基进行储罐的分析时,有限元与规范近似算法比较接近;15×104m3储罐液固耦合振动低频的振动形式比较丰富,以cosnθ、sinnθ型梁式振动为主,液体晃动低频的振动形式比较单一,即cosnθ、sinnθ型梁式振动;液固耦合振动频率对地基刚度最为敏感,储液高度与储罐高径比次之,受罐壁厚度的影响比较小;液体晃动频率对罐壁厚度和地基刚度不敏感,对储液高度与高径比则比较敏感。 相似文献
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针对大型超高压换流变压器的地震响应问题,以一超高压±800kV换流变压器为研究对象,考虑其本体中油与箱壁的相互作用建立三维有限元分析模型,采用LS-DYNA分析换流变压器的自振特性、地震作用下的动力响应规律以及换流变压器的薄弱部位。研究结果显示,对于大型超高压换流变压器,本体中油与箱壁的相互作用对结构动力响应有一定的放大作用,进行自振特性和地震响应分析时应考虑;套管体系的薄弱部位为套管的底部和中间部位,在这两个位置拉应力和压应力最大值交替出现;换流变套管体系在地震作用下的位移较大,套管顶部的导线应设置足够大的伸缩距离。 相似文献
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建立设备-结构耦合隔震体系模型,选取近断层脉冲型和非脉冲型地震波各50条,计算耦合隔震体系的动力响应。分析表明,近断层脉冲型地震动对耦合隔震体系的影响大于非脉冲型地震动,且对主体结构的影响大于对设备的影响;近断层脉冲型地震作用下的隔震层位移、层间位移、楼层加速度、设备加速度和设备位移的平均响应分别达到非脉冲型地震作用的2.25倍、2.17倍、2.24倍、1.17倍和1.20倍。进行设备-结构耦合隔震体系设计时,需考虑近断层地震动脉冲作用的影响,同时需注意引起主体结构和设备最大响应的地震动不一定相同。 相似文献
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中国核电厂抗震设计规范推荐采用的Housner模型不适用于复杂形状核电储液结构的流固耦合分析。对于AP1000和CAP1400核电站屏蔽厂房顶部非能动安全壳冷却系统重力水箱(简称PCS水箱),基于圆柱形水箱的Housner等效质量-弹簧模型,通过引入水箱体积修正参数,提出PCS水箱的三维等效质量-弹簧模型。采用有限元软件ADINA建立水箱结构流固耦合整体有限元模型以进行模态分析,计算分析PCS水箱和对应环形水箱在不同尺寸和液体深度条件下的液体晃动自振特性。对比整体有限元模型与三维等效质量-弹簧模型计算结果发现,提出的PCS水箱三维等效质量-弹簧模型能给出其内液体晃动各阶振型的液动压力合理估计值,适用于具有复杂形状的PCS水箱液动压力分析。本文的等效模型方法可推广应用于其他复杂形状水箱的液动压力分析。 相似文献
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应变率对钢筋混凝土剪力墙动态性能的影响 总被引：1，自引：0，他引：1
采用有限元软件ABAQUS中的显示动力分析模块ABAQUS/Explicit,分别对钢筋混凝土剪力墙准静态和高应变率动力荷载作用下的响应进行了数值模拟;通过比较高应变率与准静态加载下的分析结果,探讨了地震作用下应变率对钢筋混凝土剪力墙动态性能的影响。研究结果表明,受应变率效应的影响,混凝土和钢筋的动态力学行为发生了变化,动力荷载作用下的钢筋混凝土剪力墙的承载能力有一定程度的提高,故在对钢筋混凝土结构进行抗震分析时,应适当考虑应变率效应。 相似文献
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本文对板采用四结点分层板弯曲单元,对柱采用八结六面体等参单元,建立了钢筋混凝土板柱节点有限元非线性计算模型,编制了反复荷载下钢筋混凝土非线性有限元计算程序。文中介绍了作者进行的板柱节点在反复荷载作用下的试验结果,用试验数据合流验证了所建立的有限元程序的可靠性。文反柱中节点和边节 竖向剪力和低周反复水平茶叶工共同作用下的受力性能进行了全过程计算分析。 相似文献
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Most buildings in Singapore are lightly reinforced concrete structures, which are mainly designed for gravity loading only, because Singapore is an island country located in a low‐to‐moderate seismic region. The dynamic properties of a typical high‐rise residential building with a long, narrow rectangular floor plan are studied using both experimental and numerical methods. The effects of the brick infill walls and the flexible diaphragms on the dynamic characteristics of the building are discussed in detail. The results from the ambient vibration tests are correlated with the numerical results of three different finite element models with different levels of sophistication. They include a bare frame model, a frame model with brick infill walls, and a frame model with both brick infill walls and flexible diaphragms. The dynamic properties of the third model match very well with the measured results in terms of both the natural frequencies and the mode shapes. The correlation results demonstrate the respective effects of the brick infill walls and the flexible diaphragms on the dynamic characteristics of the narrow‐rectangle building structure. Copyright © 2006 John Wiley & Sons, Ltd. 相似文献
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钢筋混凝土开洞剪力墙结构抗震非线性有限元分析 总被引：6，自引：1，他引：6
本文以钢筋混凝土开洞剪力墙结构为研究对象，建立了该类结构动力非线性有限元分析计算及该类结构静力非线性pushover有限元分析计算的基本过程，并编制了相应的计算机程序．通过与实验分析结果的比较，检验了本文动力非线性有限元分析计算方法的准确程度，验证了静力非线性pushover有限元分析方法应用于开洞剪力墙抗震非线性性能评估的可靠性。 相似文献
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By advancing the technologies regarding seismic control of structures and development of earthquake resistance systems in the past decades application of different types of earthquake energy dissipation system has incredibly increased. Viscous damper device as a famous and the simplest earthquake energy dissipation system is implemented in many new structures and numerous number of researches have been done on the performance of viscous dampers in structures subjected to earthquake. The experience of recent severe earthquakes indicates that sometimes the earthquake energy dissipation devices are damaged during earthquakes and there is no function for structural control system. So, damage of earthquake energy dissipation systems such as viscous damper device must be considered during design of earthquake resistance structures.This paper demonstrates the development of three-dimensional elasto-plastic viscous damper element consisting of elastic damper in the middle part and two plastic hinges at both ends of the element which are compatible with the constitutive model to reinforce concrete structures and are capable to detect failure and damage in viscous damper device connections during earthquake excitation. The finite element model consists of reinforced concrete frame element and viscous damper element is developed and special finite element algorithm using Newmark׳s direct step-by-step integration is developed for inelastic dynamic analysis of structure with supplementary elasto-plastic viscous damper element. So based on all the developed components an especial finite computer program has been codified for “Nonlinear Analysis of Reinforced Concrete Buildings with Earthquake Energy Dissipation System”. The evaluation of seismic response of structure and damage detection in structural members and damper device was carried out by 3D modeling, of 3 story reinforced concrete frame building under earthquake multi-support excitation. 相似文献
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针对当前钢筋混凝土震后存活预测相关方法存在预测值与实际值拟合度低的问题,提出基于有限元的钢筋混凝土框架结构震后可存活概率预测方法。利用混凝土本构模型关联数值和钢筋本构模型数值计算,实现钢筋混凝土框架材料本构模型关联数值分析。结合建筑和结构施工图实现钢筋混凝土有限元模拟,将钢筋混凝土框架有限元模型的最大竖向荷载作为结构整体构造竖向极限承载力,并引入随机Pushdown方法及随机竖向IDA法得到钢筋混凝土框架震后可存活概率。经实验证明,将有限元应用至钢筋混凝土框架结构震后可存活概率预测中切实可行;预测值与实际值拟合度高于目前常用方法。所提方法的性能完善,可为该领域发展提供可借鉴的信息。 相似文献
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Most of the finite element analyses of reinforced concrete structures are restricted to two‐dimensional elements. Three‐dimensional solid elements have rarely been used although nearly all reinforced concrete structures are under a triaxial stress state. In this work, a three‐dimensional solid element based on a smeared fixed crack model that has been used in the past mainly for monotonic static loading analysis is extended to cater for dynamic analysis. The only material parameter that needs to be input for this model is the uniaxial compressive strength of concrete. Steel bars are modelled as uniaxial elements and an embedded formulation allows them to have any orientation inside the concrete elements. The proposed strategy for loading or unloading renders a numerical procedure which is stable and efficient. The whole process is applied to two RC frames and compared against existing experiments in the literature. Results show that the proposed approach may adequately be used to predict the dynamic response of a structure. Copyright © 2005 John Wiley & Sons, Ltd. 相似文献
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基于响应面的预应力混凝土桥动力有限元模型研究 总被引：1，自引：0，他引：1
建立了基于正交实验的响应面模型和精细有限元模型,并将其用于中华大桥的有限元模型修正,通过实测动力数据对修正后的有限元模型计算结果进行了验证。基于修正后的有限元模型,分析了预应力对预应力钢筋混凝土桥梁模态信息（频率和振型）的影响,以及单元类型对桥梁模态频率的影响。结果表明,修正后的有限元模型能够比较准确地反映桥梁实际结构的动力特性,基于响应面模型和遗传算法的修正方法可有效地用于大桥的健康监测和状态评估;预应力对预应力钢筋混凝土桥梁模态信息的影响较小,建模时可不予精确考虑;对于由多根预应力混凝土梁组成的桥梁体系,采用实体单元分析较好。 相似文献
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Finite element analysis of damage and failure of reinforced concrete members under earthquake loading 
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下载免费PDF全文 This paper presents a three‐dimensional analysis framework, based on the explicit finite element method, for the simulation of reinforced concrete components under cyclic static and dynamic loading. A recently developed triaxial constitutive model for concrete is combined with a material model for reinforcing steel which can account for rupture due to low‐cycle fatigue. The reinforcing bars are represented with geometrically nonlinear beam elements to account for buckling of the reinforcement. The strain penetration effect is also accounted for in the models. The modeling scheme is used in a commercial finite element program and validated with the results of experimental static and dynamic tests on reinforced concrete columns and walls. The analyses are supplemented with a parametric study to investigate the impact of several modeling assumptions on the obtained results. 相似文献