Vibration test and reinforcement analysis of some steel structure workshop building

摘要

The crane of some single-storied steel structure mold workshop runs under load, causing obvious vibration of an adjacent two-storied steel structure office building along the crane running direction. Vibration test was done by using CRAS random signal and vibration analysis system DH-5922. As test results reveal, in case of cantilever brake, the office building resonates with the mold workshop, with a resonant frequency of 3.3 Hz; for the office building, the maximum vibration velocity is 2.26 mm/s, and the maximum vibration level is 105.72 dB, neither meeting ambient vibration requirements of the office area. In this regard, plans to reinforce the office building stiffness were proposed, and the reinforcement effect was simulated by using FEM (Jinite-element method) midas. As simulation results reveal, the plan to add a cross brace is more conducive to the vibration damping of office building than the plan to expand the sectional area in the resonance direction. As results of acceptance testing after reinforcement show, for the office building, the fundamental frequency increases to 4.2 Hz; there is not resonance with the mold workshop any longer; the maximum vibration velocity decreases to 0.49 mm/s by 75%; the vibration level decreases to H2.3H dB by 22%. AH of these values meet ambient vibration requirements of office area. The building stiffness was well improved. The proposed solution can be used as reference for the vibration test and problems solving of similar items.