平动—旋转复合摩擦式隔震支座动力学性能研究
发布时间：2018-08-02 21:24
【摘要】：现有普通滑移支座存在震后位移量过大的问题,而具有自复位能力的摩擦摆支座在地震过程中会使梁体上升,易对桥梁产生附加损害。本文在现有球型抗震支座的基础上,综合超高分子量聚乙烯的耐磨性能及ZA27合金的减振性能,提出一种既能水平隔震又能竖向减振的新型平动-旋转复合摩擦式支座,在保证隔震能力的同时,提高耗能及水平承载能力,改善位移量过大的缺陷,并提供一定竖向减振能力。首先介绍了新型支座的结构和工作原理,分析建立了支座在单向及循环加载条件下的力-位移表达式,给出了分阶段的摩阻力计算公式,建立了支座的滞回模型。运用ABAQUS进行静态接触分析,模拟了支座竖直、偏转两种工况的受载情况,研究了UHMW-PE材料参数对静态结果的影响。研究了水平滑移量、卡口间隙、摩擦系数单独改变时滞回曲线、耗能量、等效阻尼比的变化规律。在确定滞回模型的基础上,研究了简谐振动输入下参数改变对支座动态性能的影响。施加地震波加速度于支座底部,研究了支座在不同地震波输入下的位移、能量及加速度响应结果。最后,建立支座-桥墩有限元模型,研究支座增加减振结构后在竖向简谐载荷作用下桥墩上部测点的竖向振动强度的减弱效果,改变ZA27合金厚度、垫板材料研究其对结果的影响。研究结论包括:(1)理论分析提出的力-位移模型有较高精度,变参数分析时,仿真计算与理论简化公式计算的耗能量最大相对误差为13.1%,阻尼比最大相对误差为9.02%,用简化公式研究支座的滞回特性可以满足工程计算要求;(2)支座旋转面2的摩擦系数对旋转阶段等效摩阻力的影响更大,影响系数约为旋转面3的2倍;(3)8度天津波作用下,支座的位移响应要明显大于taft波和EI波的结果,该支座更适合应用于硬场地及中硬场地的设防区域;(4)8度设防烈度下,增大旋转面摩擦系数对支座滑移量大小有明显的控制作用,支座最大单向位移幅值较纯平动滑移支座可减少30%以上;(5)8度设防烈度下,d0取40～80 mm时位移控制效果较好。综合考虑位移及能量响应结果,在3类地震波作用下,支座参数k2取1.5～2.5合适,d0取40～60 mm合适;(6)随着竖向简谐振动频率的增加,各测点竖向减振效果逐渐减弱,1～6 Hz频率内减振率为21.39%～67.77%,振级减小2.09～9.83 dB;6～14 Hz频率内减振率为14.63%～33.06%,振级减小1.37～3.49 dB;14～20 Hz频率内减振率为6.42%～25.68%,振级减小0.58～2.58 dB;(7)通过分析比较不同ZA27合金厚度下减振效果,考虑减振效果及使用成本,ZA27合金厚度设计时取12.5～15 mm合适。
[Abstract]:The existing ordinary sliding bearing has the problem of excessive displacement after the earthquake, and the friction pendulum bearing with the ability of self-reposition will cause the beam body to rise during the earthquake, which is easy to cause additional damage to the bridge. On the basis of the existing spherical aseismic bearing and the wear resistance of UHMWPE and the vibration absorption performance of ZA27 alloy, a new type of horizontal vibration isolation and vertical damping friction bearing is proposed in this paper. At the same time, the energy dissipation and horizontal bearing capacity are improved, the defects of excessive displacement are improved, and the vertical damping capacity is provided. Firstly, the structure and working principle of the new support are introduced, the expressions of the force-displacement of the support under unidirectional and cyclic loading conditions are established, the formula for calculating the frictional resistance in stages is given, and the hysteresis model of the bearing is established. The static contact analysis of ABAQUS is used to simulate the loading of vertical and deflection supports. The influence of UHMW-PE material parameters on the static results is studied. In this paper, the variation of horizontal slip, gap and friction coefficient is studied, which changes the time-delay return curve, energy consumption and equivalent damping ratio. Based on the hysteretic model, the influence of the parameter change on the dynamic performance of the bearing is studied under the input of harmonic vibration. The displacement, energy and acceleration response of the bearing under different seismic wave input are studied by applying the seismic wave acceleration to the base of the bearing. Finally, the finite element model of pedestal pier is established to study the weakening effect of vertical vibration intensity of the measuring point at the upper part of the pier under the action of vertical harmonic load after the support increases the vibration absorption structure, and the thickness of ZA27 alloy is changed. The effect of pad material on the results was studied. The conclusions are as follows: (1) the force-displacement model proposed by theoretical analysis has high accuracy. The maximum relative error of energy consumption and damping ratio is 13.1and 9.022.To study the hysteretic characteristics of the bearing by using the simplified formula, it can meet the requirements of engineering calculation. (2) friction of the rotary surface 2 of the bearing The influence of coefficient on the equivalent frictional resistance in rotation stage is greater. (3) under the action of 8 degrees Tianjin wave, the displacement response of the bearing is obviously larger than that of the taft wave and ei wave, and the bearing is more suitable for use in the fortification area of the hard site and the middle hard site; (4) under the intensity of 8 degree fortification, the displacement response of the bearing is obviously larger than that of the taft wave and ei wave; (4) under the 8 degree fortification intensity, the displacement response of the bearing is larger than that of taft wave and ei wave. The maximum unidirectional displacement amplitude of the bearing can be reduced by more than 30% when the friction coefficient of the rotating plane is increased, and (5) the displacement control effect is better when the maximum displacement amplitude of the bearing is 40 ~ 80 mm under the fortification intensity of 8 degree. Considering the results of displacement and energy response, under the action of three kinds of seismic waves, the support parameter k _ 2 is 1.5 ~ (2) ~ (2.5) suitable / d _ (0) = 40 ~ (60) mm. (6) with the increase of vertical harmonic vibration frequency, The vertical damping effect of each measuring point was gradually weakened. The damping rate within the frequency of 1 Hz was 21.39 and the damping rate was 67.77, and the vibration level decreased by 2.09 ~ 9.83 dBX 614 Hz. The damping rate was 14.633,33.06, and the vibration level decreased by 1.37 ~ 3.49 dB ~ 1420 Hz, the damping rate was 6.42mb / 1420Hz, the damping rate was 6.42mb 25.68, and the vibration level decreased by 6.42mb / 1420Hz, and the damping rate was 14.633.49 dB / 1420Hz. (7) by analyzing and comparing the damping effect of different thickness of ZA27 alloy, When considering the effect of vibration absorption and the application cost, the thickness of ZA27 alloy is 12. 5 mm and 15 mm.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U442.55
[Abstract]:The existing ordinary sliding bearing has the problem of excessive displacement after the earthquake, and the friction pendulum bearing with the ability of self-reposition will cause the beam body to rise during the earthquake, which is easy to cause additional damage to the bridge. On the basis of the existing spherical aseismic bearing and the wear resistance of UHMWPE and the vibration absorption performance of ZA27 alloy, a new type of horizontal vibration isolation and vertical damping friction bearing is proposed in this paper. At the same time, the energy dissipation and horizontal bearing capacity are improved, the defects of excessive displacement are improved, and the vertical damping capacity is provided. Firstly, the structure and working principle of the new support are introduced, the expressions of the force-displacement of the support under unidirectional and cyclic loading conditions are established, the formula for calculating the frictional resistance in stages is given, and the hysteresis model of the bearing is established. The static contact analysis of ABAQUS is used to simulate the loading of vertical and deflection supports. The influence of UHMW-PE material parameters on the static results is studied. In this paper, the variation of horizontal slip, gap and friction coefficient is studied, which changes the time-delay return curve, energy consumption and equivalent damping ratio. Based on the hysteretic model, the influence of the parameter change on the dynamic performance of the bearing is studied under the input of harmonic vibration. The displacement, energy and acceleration response of the bearing under different seismic wave input are studied by applying the seismic wave acceleration to the base of the bearing. Finally, the finite element model of pedestal pier is established to study the weakening effect of vertical vibration intensity of the measuring point at the upper part of the pier under the action of vertical harmonic load after the support increases the vibration absorption structure, and the thickness of ZA27 alloy is changed. The effect of pad material on the results was studied. The conclusions are as follows: (1) the force-displacement model proposed by theoretical analysis has high accuracy. The maximum relative error of energy consumption and damping ratio is 13.1and 9.022.To study the hysteretic characteristics of the bearing by using the simplified formula, it can meet the requirements of engineering calculation. (2) friction of the rotary surface 2 of the bearing The influence of coefficient on the equivalent frictional resistance in rotation stage is greater. (3) under the action of 8 degrees Tianjin wave, the displacement response of the bearing is obviously larger than that of the taft wave and ei wave, and the bearing is more suitable for use in the fortification area of the hard site and the middle hard site; (4) under the intensity of 8 degree fortification, the displacement response of the bearing is obviously larger than that of the taft wave and ei wave; (4) under the 8 degree fortification intensity, the displacement response of the bearing is larger than that of taft wave and ei wave. The maximum unidirectional displacement amplitude of the bearing can be reduced by more than 30% when the friction coefficient of the rotating plane is increased, and (5) the displacement control effect is better when the maximum displacement amplitude of the bearing is 40 ~ 80 mm under the fortification intensity of 8 degree. Considering the results of displacement and energy response, under the action of three kinds of seismic waves, the support parameter k _ 2 is 1.5 ~ (2) ~ (2.5) suitable / d _ (0) = 40 ~ (60) mm. (6) with the increase of vertical harmonic vibration frequency, The vertical damping effect of each measuring point was gradually weakened. The damping rate within the frequency of 1 Hz was 21.39 and the damping rate was 67.77, and the vibration level decreased by 2.09 ~ 9.83 dBX 614 Hz. The damping rate was 14.633,33.06, and the vibration level decreased by 1.37 ~ 3.49 dB ~ 1420 Hz, the damping rate was 6.42mb / 1420Hz, the damping rate was 6.42mb 25.68, and the vibration level decreased by 6.42mb / 1420Hz, and the damping rate was 14.633.49 dB / 1420Hz. (7) by analyzing and comparing the damping effect of different thickness of ZA27 alloy, When considering the effect of vibration absorption and the application cost, the thickness of ZA27 alloy is 12. 5 mm and 15 mm.
【学位授予单位】：西南交通大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：U442.55
【相似文献】
相关期刊论文 前10条
1 庄表中;李振华;季龙飞;孙f，
本文编号：2160775
本文链接：https://www.wllwen.com/kejilunwen/daoluqiaoliang/2160775.html
