块体基础强迫振动测试技术及工程实例

Measuring and testing technique for the forced vibration of block foundation and engineering examples

块体基础强迫振动是测试地基动力参数的一种原位测试方法,为动力机器基础设计提供地基动力参数。强迫振动测试的激振源可以是变扰力机械式激振器或者恒扰力电磁式激振器,前者因谐振性好、扰力大,测试效果更好,尤其是在扭转强迫振动测试方面,机械式综合激振器易于实现两台激振器输出扰力相位的一致性,优势更加明显。分析处理程序采用Z变换高精度频谱分析技术和振幅曲线拟合分析技术,大大提高了测试信号的频率和振幅分析精度。该项测试技术克服了电磁激振器扰力小、相位不同步的缺点,具有很好的应用价值。

The forced vibration test of block foundation is a dynamic soil in-situ test method for the dynamic parameters of foundation, which provides the dynamic parameters for the machine foundation design. The vibration source of forced vibration tests may be the changed disturbance force mechanical shaker or the constant disturbance force electromagnetic shaker, and the former gets satisfied testing effect due to the good resonance and disturbing force. Especially in the torsional forced vibration testing, the mechanical comprehensive shaker is easy to implement two phase exciter output interference power consistency, which gets more obvious advantages. The high-precision Z-transform amplitude spectrum analysis and the curve fitting analysis are used in the analysis and processing procedures, which greatly improve the accuracy of the test signal analysis of the frequency and amplitude. The test technique makes up the shortcomings of the electromagnetic shaker such as the small disturbance force and the out- synchronized phase, which will get favorable application.