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随着环形橡胶支座在文物及大型设备隔震等方面应用需求的增长,对环形橡胶支座的力学性能的准确掌握越来越重要。目前,虽然部分学者已提出环形橡胶支座的水平与竖向刚度的计算公式,但其对不同参数特征的环形橡胶支座的适应性还未经过试验验证,此外,支座水平与竖向刚度的压应力相关性也亟需进一步研究。因此,聚焦环形橡胶支座的水平与竖向力学性能,通过试验对现有计算公式进行评估,并重点研究支座的水平与竖向刚度的压应力相关性;基于试验建立环形橡胶支座的有限元模型,参数化分析不同特征参数的环形橡胶支座在不同压应力及水平剪应变下的水平刚度、竖向刚度及其内部应力分布变化规律,并量化分析不同压应力与剪应变对支座各项力学性能的影响。研究结果表明:环形橡胶支座的水平与竖向刚度均呈现出显著的压应力相关性;第一形状系数与第二形状系数对环形橡胶支座的水平与竖向力学性能均产生影响,第一形状系数对支座的竖向等效刚度与等效应力影响更大,而第二形状系数对支座的水平等效刚度影响更大;在不同加载工况下,环形橡胶支座内钢板层的Mise等效应力均远大于橡胶层。 相似文献
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厚层铅芯橡胶支座具有同时隔离水平地震动和竖向地震动的三维隔震性能,其竖向刚度是影响厚层橡胶支座竖向隔震性能的关键因素。基于厚层铅芯橡胶支座三维有限元模型,研究铅芯对厚层铅芯橡胶支座竖向刚度的影响,模型分析中考虑铅芯与周边边界的不同约束情况,研究铅芯的边界约束条件对支座竖向刚度的影响,分析结果表明,铅芯单元边界约束考虑法向可分离、切向可滑移且边界接触摩擦系数取0.9时较为符合支座实际情况。研究了铅芯直径对支座竖向刚度的影响,结果表明,铅芯对支座竖向刚度的贡献除铅芯材料自身刚度及其边界约束条件外,尚应考虑铅芯直径的影响。同时进行了支座性能试验,通过有限元分析结果与试验结果的比较,验证有限元分析方法的有效性及铅芯边界约束条件定义的合理性。 相似文献
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大跨空间结构具有空间跨度大,结构整体刚度大、受力合理、耗材少、重量轻等优点,在世界各地应用前景非常广阔。但在强震作用下,此种结构破坏严重,经济损失惨重。震害经验与理论研究表明地震动是一种复杂的多维运动,只考虑单分量水平地震作用是不够的,还应考虑竖向地震分量对整体结构的影响。在作者研制的SMA-叠层橡胶支座的基础上,针对竖向刚度大、竖向隔震效果不明显的问题,研制一种在上部串联加入碟形弹簧的新型三维隔震支座,并建立一典型的单层柱面网壳结构模型,在输入不同峰值地震动情况下,通过时程反应分析可见,SMA三维隔震支座下结构位移、加速度峰值与普通橡胶支座对比明显降低,时程曲线趋于平缓,典型的杆件轴力也有明显降低,说明了SMA三维隔震复合支座隔震效果更好。 相似文献
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《地震工程与工程振动》2015,(3)
本文针对建筑物使用的传统叠层橡胶隔震支座在使用中存在的一些问题,引进了不锈钢丝金属橡胶材料,设计并制作了新型隔震支座,对比研究了三种不同高宽比支座在不同频率、不同加载幅值下的水平剪切性能,并且研究了支座的轴向承载力以及施加轴向荷载对金属橡胶隔震支座剪切迟滞性能的影响。研究结果表明:加载频率对金属橡胶隔震支座剪切性能影响较小,金属橡胶隔震支座的耗能能力随着加载幅值的增大而增大,且随着高宽比的减小而增大;等效剪切刚度和等效阻尼比随着加载幅值、高宽比的增大而减小;支座具有较大的轴向承载能力,在施加轴向荷载后,金属橡胶隔震支座的剪切耗能能力大大增强。 相似文献
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在基础隔震结构中,当上部结构层间刚度相对较小、垂直荷载较大,且采用的叠层橡胶垫的橡胶总厚度较大时,隔震支座不仅要产生水平变形,同时也会产生竖向变形,导致上部结构产生摆动.文中推导了基础隔震结构考虑摆动的运动和控制方程,分析研究了摆动对基础隔震结构的振动控制影响.研究结果表明:基础隔震结构的摆动对控制有一定影响;隔震层转动刚度、阻尼和上部结构垂直荷载对基础隔震结构考虑摆动的振动控制有明显影响. 相似文献
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本文通过对不同参数的橡胶支座在压缩剪切变形状态下的竖向变形量进行了试验,分析了在压缩剪切变形状态下竖向变形量的特点。得出对RB支座,由剪切和弯曲产生的竖向变形随剪切应变增加而增大较快;对LRB支座,在达到一定剪切应变时,竖向变形量的增加缓慢。 相似文献
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方形多铅芯橡胶支座力学性能研究 总被引:7,自引:0,他引:7
本文通过对方形多铅芯橡胶支座竖向压缩性能试验,水平剪切性能试验以及其等效刚度、屈服强度、屈服后刚度、等效阻尼比等水平特征参数与水平剪切应变和竖向压应力的关系,特别是对其在不同方向上压缩剪切变形状态下的性能试验,分析了这种隔震支座各种水平特征参数在不同方向上变化的相关规律。得出在这种类型橡胶隔震支座在双向水平荷载同时作用下,竖向性能和水平性能较为稳定,是较为理想的桥梁结构的减隔震装置。 相似文献
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在混凝土空心砌块的空腔中填入橡胶砂形成的组合砌块(RSMCB)可作为简易隔震层应用于村镇建筑防震减灾。建立RSMCB的三维数值分析模型,进行循环剪切试验以及隔震分析,研究不同橡胶砂配比、竖向压应力、盖板尺寸和盖板埋深对隔震砌块动刚度和阻尼比的影响,分析不同的上部配重、输入地震波、橡胶砂配比、盖板尺寸和铺设方式对RSMCB垫层隔震效果的影响。结果表明:(1)橡胶砂芯组合砌块应变软化现象明显。(2)RSMCB的水平动刚度随橡胶砂配比增大而减小,随盖板埋深、盖板尺寸以及竖向压应力的增大而增大。(3)阻尼比随橡胶砂配比、竖向压应力、盖板尺寸和埋深的增大而减小,橡胶砂芯组合砌块隔震消能效果显著。在隔震数值模拟中,输入加速度在经过橡胶砂芯组合砌块垫层过滤后均有不同程度的降低,且被过滤掉大部分高频波。隔震效应随着盖板尺寸的增大而减小,上部结构配重越大,隔震效应越明显,橡胶砂配比为30%时RSMCB垫层隔震效应更好。橡胶砂芯组合砌块符合在村镇欠发达地区低成本隔震的要求,表现出广阔的应用前景。 相似文献
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防屈曲开斜槽耗能钢板剪力墙的滞回性能分析 总被引:1,自引:0,他引:1
防屈曲开斜槽耗能钢板剪力墙(简称开斜槽剪力墙)是通过在钢板上开设一定数量斜槽,并在其两侧外挂混凝土板而形成的一种新型高层钢结构抗侧耗能构件。根据开斜槽钢板剪力墙的承载机制,采用理论推导的方法得到其承载力计算公式,利用ANSYS有限元方法对开斜槽剪力墙进行模拟,并通过改变不同参数验证了计算公式的准确性。同时,采用ANSYS建立有限元模型,对开斜槽剪力墙和普通薄钢板剪力墙的滞回性能进行了对比分析。结果表明,在提供足够约束(钢板与混凝土板间隙适宜,混凝土板厚度足够)的前提下,相对于普通薄钢板剪力墙,开斜槽剪力墙改善了钢板的捏缩现象,具有更稳定的耗能能力。 相似文献
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A comparative study of performances of different base isolators for shear beam type structures is carried out. Several leading base isolation systems, including the laminated rubber bearing with and without lead plug, the resilient-friction base isolator with and without sliding upper plate, and the EDF system are considered. Displacement and acceleration response spectra for a shear beam structure subject to the accelerograms of the N00W component of El Centro 1940 and the N90W component of Mexico City 1985 earthquakes and their magnified forms are evaluated. A series of parametric studies is carried out and advantages and disadvantages of various base isolation systems are identified. Comparisons of the results with the response spectra of a fixed-base structure show that the base isolation systems are, in general, highly effective in reducing the peak acceleration transmitted to the superstructure. Thus, the deflections and stresses generated in a base-isolated structure are significantly lower than those of a fixed-base one. Furthermore, the results of the study also show that the friction-type base isolators are less sensitive to severe variations in frequency content and amplitude of the ground acceleration. 相似文献
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This paper presents an experimental research aimed at developing a new rubber‐based seismic isolator called ‘Ball Rubber Bearing (BRB)’. The BRB is composed of a conventional steel‐reinforced multi‐layered rubber bearing with its central hole filled with small diameter steel balls that are used to provide energy dissipation capacity through friction. A large set of BRBs with different geometrical and material properties are manufactured and tested under reversed cyclic horizontal loading at different vertical compressive load levels. Extensive test results indicate that steel balls do not only increase the energy dissipation capacity of the elastomeric bearing (EB), but also increase its horizontal and vertical stiffness. It is also observed that the energy dissipation capacity of a BRB does not degrade as the number of loading cycles increases. Copyright © 2011 John Wiley & Sons, Ltd. 相似文献
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A new type of steel plate shear wall (SPSW) with oval-curved architectural openings and vertically flexible horizontal connection elements is proposed. The vertical flexibility of the wall accommodates the construction settlement introduced by column contraction under the dead loads of the upper stories and allows sequential installation from the lower stories. A quasi-static cyclic loading test and finite element (FE) analysis verified the stable seismic behaviors of the ovally-perforated vertically-flexible steel plate shear wall (OVSPW). The results of FE parametric analysis showed that an OVSPW with an appropriate thickness of boundary elements effectively accommodated the construction settlement that could lead to large in-plane compression for a conventional SPSW. The horizontal connection elements made of steel tubes realized the vertical stiffness of OVSPW to less than 2% of the original value without changing the lateral stiffness. New design equations of the OVSPW were derived through integral and extreme value solutions to predict the mechanical behavior of OVSPW. 相似文献
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FRP橡胶支座压缩性能分析 总被引:1,自引:0,他引:1
将纤维复合材料板(FRP)代替传统板式橡胶支座中的加劲钢板,可以得到一种新型的橡胶支座隔振器,即FRP橡胶支座.文中首先对FRP橡胶支座的概念及特点作了基本介绍,之后,为了了解其在竖向加载情况下的力学性能,为FRP橡胶支座竖向承载力及压缩刚度的设计提供了参考,利用通用有限元程序对FRP橡胶支座进行了有限元数值模拟,对支... 相似文献
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《地震工程与工程振动(英文版)》2021,(3)
The scrap tire rubber pad(STRP) made by natural or synthetic rubber and high strength reinforcing cords exhibits substantial vertical stiffness and horizontal flexibility, and these properties can be regarded as suitable for seismic isolators for structures. The use of environmentally burdensome scrap tires as STRP isolators might be convenient as an efficient and low-cost solution for the implementation of aseismic design philosophy for low-to-medium rise buildings, especially in developing countries. Finite element analyses of unbonded square and strip-shaped STRP isolators subjected to a combination of axial and lateral loads are conducted to investigate its lateral deformation performance under seismic loading. The rubber of the isolator is modelled with Mooney-Rivlin hyperelastic and Prony viscoelastic materials, including the Mullins material damage effect. The influence of the length-to-width ratio and bearing height on the isolator performance is assessed in terms of the force-displacement relationship, horizontal stiffness, damping, and isolation periods. It is shown that the dependence of stiffness on the length-to-width ratio is significant in the longitudinal direction and minor in the transverse direction. The STRP isolators following the proposed design criteria are shown to satisfy the performance requirement at different levels of seismic demand specified by the ASCE/SEI 7-2010 seismic provisions. 相似文献