约束阻尼混凝土板在汽机基础中间平台中的应用

根据汽轮发电机组的运行经验,中间平台的振动经常明显大于顶板的振动,减小中间平台的振动是工业环境振动控制的一个新课题.为了使汽轮发电机基础中间平台的振动有较明显的改进,进行了新型吸能的阻尼材料与混凝土相结合的复合板——约束阻尼混凝土板的研究工作.通过振动及噪声的对比试验,得出约束阻尼混凝土板与普通板的模态阻尼比相比,其值的变化随频率的不同而不同;约束阻尼混凝土板的阻尼效果与板的振动型式有着密切的关系;阻尼层板和普通板相比,有一定的降噪效果,最高可降噪15dB.证明该技术对管道传递到平台上的振动及其激发的噪声可以起到减振降噪作用,为今后在动力基础工程中推广应用新型减振降噪材料进行了有益的尝试.

Application of constrained damping concrete plate to middle-platform of turbo-generator foundation

The vibration damping of middle platform is a new subject of industrial environmental vibration control,because the middle platform vibration is always much bigger than the top platform based on the perennial turbo-generator running experience.In order to reduce the middle platform vibration of turbo-generator foundation obviously,we do the research work about the constrained damping concrete plate,which is a new combination type of energy dissipation damping material and concrete.By the contrastive experiments of vibration and noise,it is concluded that the mode damping ratio of constrained damping concrete plate and common plate change together with its frequency.There are closely relationship between constrained damping concrete plate damping effect with its vibration modes.Damping layer plate can reduce much more noise than common plate;the ultimate noise reduction is 15dB.It proves that this technique can effectively reduce the vibration and noise from the pipeline to the plate.It is also a positive attempt of new type damping and noise reduction material application to future dynamical foundation.