箱板装配式钢结构楼盖舒适度分析及其调谐质量阻尼器的振动控制研究

Comfortable Level Analysis on Floors of Prefabricated Box-Plate Steel Structureswith TMD and Their Vibration Control Study

箱板装配式钢结构楼盖是一种由钢板和加劲肋焊接而成的新型装配式楼盖。通过建立若干个箱板装配式钢结构楼盖的有限元模型,研究长宽比、钢板厚度、加劲肋间距及加入调谐质量阻尼器(TMD)对楼盖舒适度的影响。研究结果表明:长宽比由6∶6增加至10∶6时,会导致竖向基频降低,降幅最大达29.6%,同时降低了人行激励产生的竖向峰值加速度;钢板厚度由6 mm增加至10 mm时,对楼盖的竖向基频影响较小,对竖向峰值加速度影响显著,降幅最大达68.8%;T型加劲肋间距由1.5 m增至3.0 m时,会导致竖向基频降低,降幅最大达33.8%,同时竖向峰值加速度增幅最大为0.1 m/s2。当钢板厚度较小且加劲肋间距过大时,容易造成楼盖局部振颤,局部产生较大的峰值加速度,加入调谐质量阻尼器能有效增加楼盖参与振动的质量,并且有效改善楼盖舒适度,满足设计标准的要求。

Prefabricated box-plate steel structure floors are a new type of prefabricated structures welded by steel sheets and stiffeners.Through construction of a number of finite element models of box-plate steel structure floors,the aspect ratio,thickness of steel sheet,stiffener spacing,and the influence of installed tuned mass dampers(TMD)on floors of comfortable levels were studied.The results showed that:the aspect ratio increased from 6∶6 to 10∶6,which could reduce vertical fundamental frequencies by up to 29.6%and reduce the vertical peak acceleration excited by pedestrains.Thicknesses of steel sheets increased from 6 mm to 10 mm,which had a little of effect on vertical fundamental frequencies of floors,but significant influence on the vertical peak acceleration by up to 68.8%;That T-stiffener spacing increased from 1.5 m to 3.0 m could reduce the vertical fundamental frequencies by up to 33.8%,simultaneouly,the vertical peak acceleration increased to 0.1 m/s 2.When the thicknesses of steel sheets were smaller and stiffener spacing was larger,it was easy to cause locad vibration for floors and larger peak acceleration locally.The tuned mass dampers(TMD)could effectively improve masses of floors in vibration as well as floor comfortable levels which could meet the specification requirements.