中文摘要：

机器扰力随机器开启时间间隔以及扰频变化呈随机性，为了研究在该随机机器激励下楼板的振动问题，结合某生产车间技改后楼板出现振动的工程实例，根据现场实测振动加速度样本数据，拟合出不同线体工作下的概率密度分布函数，与其直方图分布进行比较，利用MATLAB正态分布概率纸对其分布进行检验，并对其合成幅值进行可靠性分析。分析表明当开启机器不少于6台时楼板的响应呈正态分布特征，且拟合的正态分布概率密度函数与统计直方图分布较吻合。

英文摘要：

The machine force is stochastic with the change of starting time and frequency. The vibration prob- lem of a slab under this type of force is studied. Based on the testing sample data of acceleration from an engi- neering project, the probability density function （PDF） of different lines were fitted and used to compare with the histograms. Using the normal distribution probability tool of MATLAB, the distribution funtion was checked. The reliability of the vibration amplitude was analyzed. The results present that, when the number of machines at work is not less than 6, the resopnse is normal distributed, and the fitted normal distribution PDF function is agreed well with the statistics histogram.