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1.
研究目的:为多塔斜拉桥在一致激励和非一致激励下地震响应的研究提供地震模拟振动台全桥试验方法,并有助于加强多塔斜拉桥抗震性能和抗震设计的认识。创新要点:1.建立了地震模拟振动台多台阵试验方法,并首次将其应用于多塔斜拉桥全桥比例缩尺模型的地震响应分析之中;2.通过地震模拟振动台试验,揭示了多塔斜拉桥在多点一致激励和多点非一致激励的地震响应特性并提出了多塔斜拉桥在强震下的破坏模式。研究方法:1.基于动力相似理论,设计与制作了多塔斜拉桥的全桥比例缩尺模型(图2);2.利用地震模拟振动台多台阵试验,根据在不同地震波作用下和考虑行波效应后多塔斜拉桥模型的主梁和主塔响应,分析了多塔斜拉桥在多点一致激励和多点非一致激励的地震响应特性(图5~图8);3.根据在地震波不同强度作用下多塔斜拉桥模型的主梁和主塔响应,分析了多塔斜拉桥在强震下的破坏模式和地震响应(图9)。重要结论:1.江心波作用下该多塔斜拉桥的地震响应大于其他三种地震波;2.多塔斜拉桥在抗震设计时需要考虑行波效应的影响;3.在El-Centro波的加速度峰值高达4.0 m/s2时,多塔斜拉桥模型出现了支座破坏。 相似文献
2.
研究目的：创新要点：为多塔斜拉桥在一致激励和非一致激励下地震响应的研究提供地震模拟振动台全桥试验方法,并有助于加强多塔斜拉桥抗震性能和抗震设计的认识。1．建立了地震模拟振动台多台阵试验方法,并首次将其应用于多塔斜拉桥全桥比例缩尺模型的地震响应分析之中;2．通过地震模拟振动台试验,揭示了多塔斜拉桥在多点一致激励和多点非一致激励的地震响应特性并提出了多塔斜拉桥在强震下的破坏模式。研究方法：1．基于动力相似理论,设计与制作了多塔斜拉桥的全桥比例缩尺模型（图2）;2．利用地震模拟振动台多台阵试验,根据在不同地震波作用下和考虑行波效应后多塔斜拉桥模型的主梁和主塔响应,分析了多塔斜拉桥在多点一致激励和多点非一致激励的地震响应特性（图5～图8）;3．根据在地震波不同强度作用下多塔斜拉桥模型的主梁和主塔响虚,分析了多塔斜拉桥在强震下的破坏模式和地震响应（图9）。重要结论：1．江心波作用下该多塔斜拉桥的地震响应大于其他三种地震波;2．多塔斜拉桥在抗震设计时需要考虑行波效应的影响;3．在El-Centro波的加速度峰值高达4．0m／s^2时,多塔斜拉桥模型出现了支座破坏。 相似文献
3.
程怡 《福建工程学院学报》2018,(4):320-325
以某跨径为110 m的独塔异形斜拉桥为工程背景,通过非线性有限元分析对斜拉桥在强震作用下的地震响应特性及减震措施进行了研究,得出如下结论:相比Lander-amboy波,卓越周期与桥梁固有周期较为接近的Cerro Prieto波能够引起结构较大的地震响应。行波效应能够显著增大工程背景斜拉桥的地震响应,且随着视波速的增大,桥梁的加速度响应明显增大。阻尼系数25 000 kN·s/m为工程背景斜拉桥的最优粘滞阻尼器设计参数,且在塔梁连接处安装该参数粘滞阻尼器后,斜拉桥减震效果显著,尤其能明显减小结构的位移响应。 相似文献
4.
采用有限元软件对某高墩大跨径预应力混凝土曲线连续刚构桥进行建模,并对该桥地震时程响应进行分析,研究了在不同地震波下的内力和变形影响。计算结果表明,两种地震波一致激励产生的内力分布规律和最大内力、最大位移位置基本一致;在进行桥梁地震设计时,需进行不同地震波下的桥梁抗震时程响应分析,同时应考虑地震反应持续时间的影响。 相似文献
5.
通过理论研究和数值计算，详细分析了大跨径钢管混凝土双肋拱桥的侧倾稳定性和地震响应。首先，根据双肋拱桥结构在竖向均布荷栽作用下的侧倾稳定临界力的近似解析解，讨论了横撑设置、横撑刚度等因素对稳定性的影响。其次，基于多点激振理论和拟静力位移概念，介绍了拱桥结构的动力特点和地震动作用下的响应，并讨论了行波效应的影响。分析表明，地震行波作用对大跨度拱桥影响很大，横撑设置对稳定性敏感。 相似文献
6.
在通用有限元程序MSC.MARC中加入基于纤维模型编制的THUFIBER程序和三维实体单元模型分别模拟钢筋混凝土桥墩和桥梁上部结构,建立了高墩大跨连续刚构桥的有限元模型。采用汶川地震记录,针对四川境内某一实际桥梁,分析了行波效应对其地震反应的影响。结果表明:波速较小时,行波效应对墩顶的位移有利。墩底是地震分析时的危险截面,行波效应对结构反应较为复杂,在某些截面上可能加大,也可能降低,在抗震设计时,应考虑行波效应的影响。 相似文献
7.
赵娟娟 《天津职业院校联合学报》2013,15(2):44-48
文章以山东济南建邦三塔斜拉桥为研究对象,采用有限元软件建立该桥有桩和无桩两种模型,进行了动力特性分析,并在不同工况下进行反应谱和弹性时程分析。两种模型的地震响应的结果表明,桩土效应对结构位移和内力影响较大,在对大跨度支撑体系斜拉桥进行抗震分析时,应该考虑桩土效应。 相似文献
8.
考虑阻尼之组合结构的动内力局部效应修正 总被引：2，自引：1，他引：1
以往对结构进行动力分析常常忽略局部效应的影响,但实践证明,局放效应在某些结构中占有很大的比重,为得到精确的动力响应,必须考虑局部效应本文在已有的基础上,提出了考虑阻尼之组合结构在地震作用下局部效应的计算方法通过对结构动内力进行局部效应修正前后求解精度的对比,证明了考虑局部效应的重要性．最后,本文对核反应堆堆顶屏蔽给构进行了局部动内力分析,得出了一些有意义的结论。 相似文献
9.
为了研究连续梁桥主梁与横向挡块之间的碰撞-摩擦耦合效应及其对桥梁结构地震响应的影响,以一座钢筋混凝土连续梁桥为研究对象,基于OpenSees有限元程序建立了3座桥梁有限元模型,其中考虑了纵向、横向的碰撞单元及支座的失效.在此基础上进行了连续梁桥在双向地震激励作用下考虑碰撞-摩擦耦合作用的地震响应分析,并进行了影响参数分析.分析结果表明,碰撞-摩擦耦合作用会改变桥梁结构的内力分布并对桥墩产生额外的扭转力,摩擦系数及纵向碰撞间隙是2个重要因素.合理的摩擦系数及纵向碰撞间隙能够显著降低主梁地震响应,并且有效地将部分作用于固定墩的主梁惯性力转移至滑动墩,从而减小固定墩地震需求并改善连续梁桥结构的抗震性能. 相似文献
10.
颜桂云余勇胜袁宇琴李环辉张东鹏 《福建工程学院学报》2021,(4):307-314
根据远场类谐和地震动、普通地震动反应谱与规范反应谱之间的包络关系,选取输入结构的地震动加速度峰值?建立双柱墩式抗震梁桥,分析同峰值加速度的远场类谐和地震动和普通地震动作用下双柱墩式梁桥主梁、墩柱的地震响应等,揭示远场类谐和地震动作用下双柱墩式梁桥的动力响应与失效机理?采用SR模型模拟双柱墩抗震梁桥墩底的SSI效应,分析远场类谐和地震动作用下梁桥地震响应变化规律。结果表明,远场类谐和地震动对桥梁的地震响应为普通地震动作用的1.5倍以上,其设防烈度至少应提高一度才能保证桥梁的安全?墩-系梁连接点处弯矩随桩土刚度减小而增大,有可能会引起桥墩弯曲破坏。 相似文献
11.
INTRODUCTION Adequate information on dynamic soil proper-ties, especially dynamic shear modulus and dampingratio, is essential for accurate computations of groundresponse and soil-structure interaction problems.Many experimental investigations carried out onsandy soils through resonant column test or improvedcyclic triaxial test in early studies (Hardin and Richart1963; Hardin and Black, 1968; Drnevich and Richart,1970; Seed and Idriss, 1971; Kokusho, 1980) showedthat the small … 相似文献
12.
The influence of the change of structure plane size on seismic response was studied for a soil-structure interaction system. Based on the finite element method, a soil-structure interaction calculation model was established to analyze the seismic response by changing the structure plane size and choosing different earthquake waves for different soil fields. The results show that when the natural periods of vibration for different structure plane sizes are close, under the same earthquake wave, the total displacement on the top layer of the structure and the foundation rotation displacement decrease with the increase of structure plane size, and the proportion of superstructure elastic selfdeformation displacement to the total displacement increases with the increase of structure plane size. While for different types of sites and seismic waves, under the horizontal and vertical seismic waves, the seismic responses of different plane sizes have a similar change rule. 相似文献
13.
FOR THE GEO一TEEHNIEAL DESI，PARAMETERS OF 5011，EOMPARISON OF SEISMIE RESPONSES BASED ON DIFFERENT THE UNEVEN DISTRIBUTION OF THE DIFFERENT KINDS OF 5011 METHODS TO EVALUATE THE 5011 FUNETIONS.IN ADDITION， AND SAMPLING LOCATIONS DURING EXPLORATION AND I… 相似文献
14.
Collapses of transmission towers were often observed in previous large earthquakes such as the Chi-Chi earthquake in Taiwan
and Wenchuan earthquake in Sichuan, China. These collapses were partially caused by the pulling forces from the transmission
lines generated from out-of-phase responses of the adjacent towers owing to spatially varying earthquake ground motions. In
this paper, a 3D finite element model of the transmission tower-line system is established considering the geometric nonlinearity
of transmission lines. The nonlinear responses of the structural system at a canyon site are analyzed subjected to spatially
varying ground motions. The spatial variations of ground motion associated with the wave passage, coherency loss, and local
site effects are given. The spatially varying ground motions are simulated stochastically based on an empirical coherency
loss function and a filtered Tajimi-Kanai power spectral density function. The site effect is considered by a transfer function
derived from 1D wave propagation theory. Compared with structural responses calculated using the uniform ground motion and
delayed excitations, numerical results indicate that seismic responses of transmission towers and power lines are amplified
when considering spatially varying ground motions including site effects. Each factor of ground motion spatial variations
has a significant effect on the seismic response of the structure, especially for the local site effect. Therefore, neglecting
the earthquake ground motion spatial variations may lead to a substantial underestimation of the response of transmission
tower-line system during strong earthquakes. Each effect of ground motion spatial variations should be incorporated in seismic
analysis of the structural system. 相似文献
15.
为了分析塔式起重机的动力特性及在不同水平下的地震响应,首先借助ANSYS有限元分析软件,对塔式起重机进行模态分析;其次对塔式起重机的有限元模型分别输入EI Centro、Taft及汶川什邡八角站三种激励地震波,分析塔身和水平横梁节点地震响应,最后讨论塔式起重机的抗震设计要点及隔震措施。结果表明：塔式起重机的塔臂疲劳主要由地震反应谱中的窄带过程控制,反之,塔臂的折断破坏是由宽带过程起主要作用。 相似文献
16.
Shaking table test of pile-water-pier superstructure 总被引：1，自引：1，他引：0
The model test of seismic simulation shaking table is an important method to study the seismic design of bridge structure. In order to evaluate the seismic response and dynamic characteristics of pile-water-pier system for developing more reliable design procedures, shaking table model tests of a submerged bridge pier system, including pile groups-cap-pier and inertia mass, were conducted. Since different similitude laws corresponding to different test objectives affected the validity of test results, the similitude law with the aim to consider the effect of hydrodynamic pressure was proposed and confirmed through an actual example. Based on the test results, the effect of water around model on seismic response under seismic excitation input was analyzed and the failure level was judged by observing the variation of basic frequency. The test results indicate that the transfer function of analytical model with water is different from that without water, the natural frequency without water is always higher than that with water, and the first modal shapes are various. It is also concluded that the similitude law is suitable for practical application and the dynamic characteristics and seismic response of the structure system can be changed because of the existence of the surrounding water, which should be paid much attention in the further investigation. 相似文献