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高层建筑利用TLD减小风振反应的研究 总被引：1，自引：0，他引：1
本文利用调频液体阻尼器（TLD）对高层建筑风振响应进行了控制研究。通过理论计算与分析探讨了TLD中液体质量变化及TLD安装位置的不同对所研究的高层结构风振控制作用的影响，给出了合理的计算结果。 相似文献
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本文对海洋平台结构地震反应运动方程中的非线性流体阻力项,按振动一周力作功相等的原则,等效为线性的粘滞阻尼力。在等效的过程中,作者提出了所谓“拟静态位移”的概念,用它代替等效粘滞阻尼系数中与频率有关的位移幅值,从而使计算大为简化。文中还以一简单的海洋工程结构为例,按该近似方法计算了它在某地震记录输入下的反应,并与“Fourier变换-时域迭代混合法”计算的结果进行了对比。结果表明:利用本文的近似方法计算海洋平台结构的地震反应不仅速度快、费用少,而且具有较高的精度。 该法还可以推广应用于同时受地震荷载及波浪荷载作用的海洋平台结构的反应分析。 相似文献
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不同参数对TLD振动控制作用的影响 总被引：2，自引：0，他引：2
本文通过理论分析与计算,研究了对应于不同频率的TLD装置和荷载输入,TLD对建筑结构的控制作用,讨论了不同参数对TLD振动控制作用的影响,给出了对应于一定荷载频率范围TLD对结构振动控制作用较好的参数取值。 相似文献
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高层建筑利用TLD减震的实例计算 总被引：6，自引：2，他引：4
本文进行了高层建筑利用调频液体阻尼器（TLD）减震的实例计算。计算结果表明,对高层建筑而言,同时控制结构多振型反应比只控制结构第一振型反应效果好。 相似文献
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导管架式海洋平台结构阻尼隔振体系及其减振效果分析 总被引：10，自引：2，他引：10
导管架式海洋平台结构是当前应用最广的一种平台结构形式。本文研究导管架式海洋平台结构阻尼隔振体系及其减振效果。针对导管架式海洋平台结构的型式与特点，为了充分发挥阻尼器的耗能减振作用，提出了在平台结构导管架端帽和甲板之间设置柔性阻尼层的新型阻尼隔振方案。针对渤海JZ20－2MUQ平台结构，建立了海洋平台结构阻尼隔振体系简化计算模型，研究了隔振层参数与结构阻尼比的关系以及它们对结构整体和隔振层层间相对位移的控制效果；进行了多种冰荷载工况和地震工况的数值模拟。结果表明，阻尼隔振方案是导管架式海洋平台结构的一种有效的减振措施。 相似文献
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高柔结构在强风或地震等环境荷载作用下，往往会产生较大的变形和位移。采用调谐液体阻尼器对结构进行控制时，需要选择合适的水箱尺寸和水深，以期获得最好的减振效果。以往的调谐液体阻尼器参数优化往往基于等效线性模型或在小幅值激励下有较好精度的非线性浅水波动模型。采用了一种具有非线性阻尼和非线性刚度的等效调谐质量阻尼器模型对影响调谐液体阻尼器减振效率的主要参数进行了优化，该模型不再受小幅值激励的限制。优化结果表明，激励幅值对TLD的最优参数和减振效果有明显影响，同时水箱长度对TLD减振效果也有明显影响，这是基于线性模型TLD优化不能得到的结论。 相似文献
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《地震工程与工程振动》2015,(5)
通常采用数值模拟和小比例尺试验的方法研究调谐液体阻尼器(TLD)对结构的减振控制效果。由于TLD依靠水的晃动来提供减振力,精确的数值模型不易建立;另外,振动台模型试验又只能进行小比例尺试验,难以真实反映原型结构性能。为了解决这个问题,提出基于等效力控制方法的振动台子结构试验方法,以真实揭示TLD减振控制结构的抗震性能。通过试验研究得到如下结论:(1)惯性试件的振动台子结构试验结果与精确解吻合很好,表明基于等效力控制方法振动台子结构试验具有很好的精度;(2)TLD减振控制三层钢框架系统的振动台全结构和子结构试验结果吻合较好,进一步证明了基于等效力控制方法振动台子结构试验具有很好的精度。 相似文献
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《地震工程与工程振动》2015,(5)
摇摆结构体系是最近几年发展起来的新型结构,研究表明摇摆柱施加于海洋平台上可有效降低平台的动力反应。基于摇摆柱体系的新型海洋平台结构形式,以JZ20-2北高点井口平台为例,利用ANSYS有限元软件对该结构体系进行了地震作用和冰力荷载下的数值仿真分析,计算了摇摆柱与海洋平台之间的连接杆在不同刚度、不同数量时的平台结构位移和加速度反应。分析结果表明,连接杆的刚度和数量对海洋平台结构的位移和加速度反应有较大影响,当其达到某一值或在特定范围内时,对海洋平台振动的控制效果最为明显,为海洋平台——摇摆结构体系的实际应用提供了理论依据。 相似文献
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大跨度斜拉桥钢塔施工阶段制振用TMD、TLD装置及其性能试验 总被引：2，自引：0，他引：2
本文以南京长江第三大桥为例,研制了用于钢塔施工阶段涡激振动响应制振的制振器TMD和TLD。对制振装置以及其所采用的一些关键技术进行了说明。通过振动台试验测试了制振器的动力特性。根据试验结果,对TMD的工作性能,即装置的频率特性、阻尼特性、起动时所需的外激励水平及装置的框架刚度等,进行了评价分析;对TLD实现了其阻尼方案的优化,并确定了其工作时的阻尼隔栅状态。确认了制作完成的制振器具有良好的工作性能。 相似文献
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Fixed offshore platforms supported by pile foundations are required to resist dynamic lateral loading due to wave forces. The response of a jacket offshore tower is affected by the flexibility and nonlinear behaviour of the supporting piles. For offshore towers supported by clusters of piles, the response to environmental loads is strongly affected by the pile–soil–pile interaction. In the present study, the response of fixed offshore platforms supported by clusters of piles is investigated. The soil resistance to the pile movement is modelled using dynamic p–y curves and t–z curves to account for soil nonlinearity and energy dissipation through radiation damping. The load transfer curves for a single pile have been modified to account for the group effect. The wave forces on the tower members and the tower response are calculated in the time domain using a finite element package (ASAS). Several parameters affecting the dynamic characteristics of the platform and the platform response have been investigated. 相似文献
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Tuned liquid damper(TLD) and tuned liquid column damper(TLCD) are two types of passive control devices that are widely used in structural control. In this study, a real-time hybrid simulation(RTHS) technique is employed to investigate the difference in control performance between TLD and TLCD. A series of RTHSs is presented with the premise of the same liquid length, mass ratio, and structural parameters. Herein, TLD and TLCD are physically experimented, and controlled structures are numerically simulated. Then, parametric studies are performed to further evaluate the different performance between TLD and TLCD. Experimental results demonstrate that TLD is more effective than TLCD under different amplitude excitations. 相似文献
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针对地震-台风耦合作用下的近海导管架海洋平台,运用Morison方程将台风对导管架平台的拖曳力及波浪对导管架平台的拖曳力和惯性力施加在结构上,并在基底施加地震动,建立地震-台风耦合作用下的运动方程。通过模态分析,确定结构的基本自振频率,进而选取卓越频率与该频率较为接近的海底地震动进行输入。对通过数值模型计算得到的导管架平台动力响应,参考相关文献中的限值,对耦合作用下的平台进行安全评估,给出了近海导管架海洋平台在地震-台风耦合作用下的损伤状态评定标准。本文关于导管架平台动力响应的统计结果,对导管架结构性态设计具有一定参考意义。 相似文献
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大连国贸大厦高层水箱风振控制研究及应用 总被引：3，自引：1，他引：2
本文针对一实际工程结构———大连国贸大厦,研究了风荷载作用下调液阻尼器的减振控制作用。首先建立了该结构的简化计算模型,利用Davenport谱给出了模拟风荷载。在大厦所处位置进行多次测量,得到实际风速样本。选取其中风速较大、过程平稳的样本,对实测样本和模拟样本的频谱进行比较,验证了模拟风荷载的合理性。文中将大厦顶层的生活水箱设计成可减小结构位移及加速度反应的控制装置TLD(tuned liqu id damper),根据不同工况进行数值计算,选出最佳方案,设计出可实际应用、并达到一定减振效果的减振水箱,以提高大厦在风荷载作用下的舒适度。 相似文献
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This study investigates the control of jacket‐type offshore platforms. The deck displacement of jacket‐type offshore platforms can be controlled using both passive and active control mechanisms. Among the passive control mechanisms, a tuned mass damper concept is studied in this paper. Active control mechanisms considered here include the active mass damper, the active tendon mechanism and the propeller thruster. An optimal frequency domain approach to active control of wave‐excited platforms is used in which the H2 norm of the transfer function from the external disturbance to the regulated output is minimized. In this study, the hydrodynamic drag force is evaluated using the JONSWAP wave spectrum. Unlike conventional linearization approaches, the influence of non‐linearity in the drag force is retained in this scheme by expressing the non‐linear force components in terms of higher‐order convolutions of the water‐particle velocities. To demonstrate the effectiveness of this scheme, the platform performance with and without control devices under different sea states is evaluated. It is demonstrated that the control devices are useful in reducing the displacement response of jacket‐type offshore platforms, especially when the wave forces are concentrated at frequencies close to the natural frequencies of the platform. This becomes especially significant in deep waters because the natural frequencies of jacket‐type platforms fall closer to the dominant wave frequencies in deep waters. Adding control devices to deep water platforms will ensure a reduction both in the global response of the platform and in localized effects, such as the fatigue of welded joints. Copyright © 2001 John Wiley & Sons, Ltd. 相似文献
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Yasser E. Mostafa M. Hesham El Naggar 《Soil Dynamics and Earthquake Engineering》2006,26(12):1127-1142
Storms, hurricanes, and earthquakes may cause seabed instability, especially if the seabed is weak. The seabed instability, manifested in movement of soil layers, exerts lateral forces that may cause large stresses in offshore foundations. The induced stresses may compromise the stability of the foundation and supported structure. The effect of seabed instability on a fixed offshore structure is examined in this study. The method used accounts for soil nonlinearity, dynamic soil resistance, and pile–soil–pile interaction within the stable soil layer. Dynamic p–y curves, dynamic t–z curves and q–z curves have been used to simulate the soil resistance in the lateral and axial directions. The effect of different parameters that influence the response of offshore structures to seabed instability is evaluated. The parameters considered include the value of soil movement, the sliding layer depth, the wave loading, the pile flexibility, the soil movement profile, and the axial loading at the pile head. The response predicted using the proposed analysis compared well with that calculated using a boundary element solution for a case history of a failed offshore platform. 相似文献
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损伤和缺陷对海洋平台抗冰抗震性能的影响 总被引：1，自引：0，他引：1
现役导管架式海洋平台可能会存在裂纹、凹痕、腐蚀等缺陷和损伤,并可能受到海洋生物附着及地基土冲刷的影响,这些问题将减小构件强度或者放大荷载作用.取一座导管架海洋平台为例,应用动力时程及整体推进法进行分析,对比损伤前后动冰力作用下结构响应、结构抗冰能力曲线及剩余强度储备系数,并取3个地震波对损伤前后结构的地震响应、抗震能力曲线、抗震安全裕度系数进行对比.结果显示损伤和缺陷极大地降低了海洋平台抗冰抗震性能,对现役海洋平台的检测和维修也有一定借鉴意义. 相似文献
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Numerical simulations of a single‐degree‐of‐freedom (SDOF) structure, rigidly supporting a tuned liquid damper (TLD) and subjected to both real and artificially generated earthquake ground motions, show that a properly designed TLD can significantly reduce the structure's response to these motions. The TLD is a rigid, rectangular tank with shallow water in it. Its fundamental linear sloshing frequency is tuned to the structure's natural frequency. The TLD is more effective in reducing structural response as the ground excitation level increases. This is because it then dissipates more energy due to sloshing and wave breaking. A larger water‐depth to tank‐length ratio than previous studies suggested, which still falls within the constraint of shallow water theory, is shown to be more suitable for excitation levels expected in strong earthquake motions. A larger water‐mass to structure‐mass ratio is shown to be required for a TLD to remain equally effective as structural damping increases. Furthermore, the reduction in response is seen to be fairly insensitive to the bandwidth of the ground motion but is dependent on the structure's natural frequency relative to the significant ground frequencies. Finally, a practical approach is suggested for the design of a TLD to control earthquake response. Copyright © 2000 John Wiley & Sons, Ltd. 相似文献