Hans Journal of Civil Engineering
Vol.3 No.06(2014), Article ID:14429,10 pages
DOI:10.12677/HJCE.2014.36024

Site Test on Vibration Influence Induced by Large Scale Shaking Table Array

Xun He, Guangzhen Li, Xiaosong Ren, Gang Zong

Research Institute of Structural Engineering and Disaster Reduction in College of Civil Engineering, Tongji University, Shanghai

Email: hexun215@126.com

Received: Oct. 4th, 2014; revised: Nov. 5th, 2014; accepted: Nov. 14th, 2014

ABSTRACT

In order to evaluate the effect of vibration induced by large scale shaking table array, site test on the ground vibration acceleration was done inside and outside the civil lab. Two conditions, as no table working and 2 tables working with sines input of different frequencies from 1 to 40 Hz and peak acceleration of 0.5 g are included. By vibration attenuation curve from the test result, the damping ratio of different frequency is got and the effectiveness of the large mass stiffness is also verified for vibration reduction.

Keywords:Shaking Table Array, Ground Borne Vibration Test, Attenuation Rate of Ground Vibration, Damping Ratio

Email: hexun215@126.com

1. 测试概况

2. 测试仪器

3. 脉动测试

3.1. 时频分析原理

Margenau-Hill类型的时频分布主要分为有两种基本形式，即为Margenau-Hill时频分布和Margenau-Hill-Spectrogram时频分布[4] [5] ，其定义[6] [7] 分别如下：

1) Margenau-Hill时频分布

Margenau-Hill时频分布的定义如下：

(1)

Figure 1. Plan and cross-section of shaking table trenches

Figure 2. EpiSensor acceleration tester

Figure 3. EpiSensor acceleration sensor

2) Margenau-Hill-Spectrogram时频分布

Margenau-Hill-Spectrogram时频分布的定义如下：

(2)

3.2. 数据分析

4. 正弦波加载测试

4.1. 测试工况选择

4.2. 测点布置

Table 1. Statistics of peak value of ground borne vibration along vertical direction (m/s2)

Table 2. Parameters of sine input wave

Figure 4. Vertical acceleration time history of outdoor ground borne vibration

Figure 5. Vertical acceleration time history of indoor ground borne vibration

Figure 6. Time-frequency distribution spectrogram of ground borne vibration along vertical direction (indoor)

Figure 7. Time-frequency distribution spectrogram of ground borne vibration along vertical direction (outdoor)

Figure 8. Power spectral density spectrum of ground borne vibration along vertical direction (indoor)

Figure 9. Power spectral density spectrum of ground borne vibration along vertical direction (outdoor)

Figure 10. Time-frequency distribution spectrogram of ground borne vibration along longitudinal direction (indoor)

Figure 11. Time-frequency distribution spectrogram of ground borne vibration along transverse direction (indoor)

Figure 12. Layout of test points along longitudinal and transverse direction

4.3. 结果分析

(3)

Figure 13. The time history of measured acceleration

Figure 14. Attenuation curve of free vibration

Figure 15. The longitudinal acceleration attenuation ratio

Figure 16. The transverse acceleration attenuation ratio

Table 3. Damping ratio under different frequency excitation

5. 小结

1. [1]   任晓崧 (2013) 对于大型土木实验室建设的认识—以同济大学新建多功能振动试验中心项目为例. 实验室研究与探索, 23, 178-181.

2. [2]   陶余飞 (2012) 非固定多点激励条件下的大型动力基础振动影响分析. 硕士论文, 同济大学, 上海.

3. [3]   Ren, X.S., Tao, Y.F. and Zhou, B. (2013) Study on vibration induced by the shaking tables array in large scale civil lab. Proceedings of the 13th East Asia-Pacific Conference on Structural Engineering & Construction (EASEC-13), 11-13 September 2013, Sapporo, 8 p.

4. [4]   葛哲学, 陈仲生 (2006) MATLAB时频分析技术及其应用. 人民邮电出版社, 北京, 2-5, 66-82.

5. [5]   Boashash, B. (2003) Time frequency signal analysis and processing. Library of Congress Cataloging in Publication Data.

6. [6]   Papandreou-Suppappola, A. (2003) Applications in time-frequency signal processing. CRC Press LLC, Boca Raton.

7. [7]   Auger, F., Flandrin, P., Goncalves, P. and Lemoine, O. (1995) Time-frequency toolbox.

8. [8]   (1983) 动力机器基础设计手册. 建筑工业出版社, 北京.