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第 40 卷 第 3 期              卢铃等: 变压器振动在典型建筑结构中的衰减特性                                           475


                 multi-story buildings, their slopes were 31.87 and 20.07, respectively, and the attenuation rate of the former
                 was about 1.6 times that of the latter. It could be seen that transformer vibration attenuation rate in a shear
                 wall building would be faster than that in a frame building when the height and number of floors were the
                 same. When a building structure was the same, the attenuation rate of vibration in a high-rise building would
                 be slightly higher than that in a multi-story building. In the case of 0 ∼ 80 Hz vibration, the attenuation rate
                 of vertical Z-weighted vibration level in a high-rise building with a shear wall structure was about 2.4 times
                 that of a high-rise building with a frame structure. The vibration attenuation rate of a shear wall multi-story
                 building was about 3.7 times that of a frame multi-story building. On this basis, the single value and frequency
                 division prediction model of the vibration propagating to different floors of shear wall and frame buildings
                 were established, which can provide the basis for the prediction and control of indoor vibration caused by
                 transformer.
                 Keywords: Transformer vibration; Building structure; Numerical simulation; Attenuation characteristics



             0 引言


                 随着城市化的快速推进和居民用电负荷的不
             断增长,居民区配电变压器数量持续增加。位于建
             筑物内的变压器在运行过程中,其振动可通过建筑
             结构传播,产生室内二次结构噪声污染                  [1−4] 。当建
             筑物局部结构固有频率与变压器振动频率接近时,
             室内二次结构噪声尤为突出             [5] 。为控制变压器振动                     (a) ಴౶ፇ౞           (b) ҝҧܗፇ౞
             引起的室内二次结构噪声污染,有必要研究掌握居
                                                                        图 1  典型多层建筑结构有限元模型
             民区10 kV配电变压器振动在不同类型建筑结构中
                                                                  Fig. 1  Finite element models of typical multi-
             的衰减特性。                                               story building structures
                 本文采用有限元法建立两种典型建筑 (剪力
             墙结构和框架结构) 的三维有限元模型, 通过                            2 仿真方法及参数设置

             仿真研究变压器振动在典型建筑结构中的衰减
                                                                   模型单元的选择是进行建筑结构动力响应分
             特性。
                                                               析的关键,相比于固体单元,三维梁单元和板单元
                                                               可以在保证计算精度的前提下大幅降低计算量。因
             1 典型建筑结构模型
                                                               此,梁和柱采用两节点空间线性梁单元进行仿真,楼
                 分别建立典型多层 (8 层)、高层 (20 层)          [6]  框架、    板采用四节点曲面薄壳或厚壳单元进行仿真。
             剪力墙结构建筑模型,其中地下室均为2 层,建筑层
                                                               2.1  阻尼参数
             高均为 3 m,负一层楼板厚度均取 200 mm,其余楼
                                                                   变压器振动以弹性波的形式在建筑结构中传
             层楼板厚均为 120 mm。框架建筑柱间距 4.5 m,柱
                                                               播,结构阻尼通常采用瑞利阻尼 C 进行分析,其表
             截面800 mm × 800 mm,梁截面300 mm×600 mm;
                                                               达式为
             剪力墙建筑墙厚 200 mm。主要建筑材料为混凝土
             C40,根据《混凝土结构设计规范》 ,混凝土C40的                                        C = αM + βK,               (1)
                                           [7]
             泊松比、密度和杨氏模量分别为0.2、2500 kg/m 和
                                                       3
                                                               其中,M 为质量阻尼,K 为刚度阻尼;α 和β 是常数,
             32.5 GPa。建筑结构底部设为固定支座,并约束 X、
                                                               分别是质量阻尼系数和刚度阻尼系数,通过式 (2)、
             Y 、Z 方向的平移和转动。图1为多层建筑三维有限
                                                               式(3)获得:
             元模型结构示意图。
                                                                                    2ω 1 ω n
                                                                               α =         ξ,             (2)
                                                                                    ω 1 + ω n
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