Human-induced Vibration Analysis And Vibration Reduction Design Of Long-span Floor Structures

With an increasing demand for structural function and aesthetics,the wide application of new structural materials characterized as light weight and high strength,public buildings such as museums,stadiums and railway stations are constructed to be large-span and low-frequency.This kind of trend makes public buildings soft and light,which makes the frequency of the structure close to that of the human walk.Considering the fact that the human traffic at these structures are quite heavy,it's easy to cause resonance and unbearable vibration.The unbearable vibration will make people feel uncomfortable,give them bad experiences,which may induce public discontent and complaint,and may even cause panic and lead to riot and stamped accident eventually.To prevent accidents mentioned above and create a comfortable environment for people in these large-span structures,it's of great social significance and engineering value to carry out the research on the human-induced vibration of large-span structures.Taking a animation & comics museum as the example of the large-span floor structure,human-induced vibration analysis,vibration serviceability evaluation and control are studied in this dissertation.The research is based on but not limited to this large-span floor structures,the methods proposed in this dissertation can also be applied to some other forms of structures when carrying out the similar research in the field of human-induced vibration.The main research works are as follows:Firstly,the vertical dynamic interaction between human and structure was studied.Based on the D'Alembert's principle theory and the orthogonality of the mode shape function,the free vibration equation of the human-floor coupled system was established with the mass-spring-damper model simulating the human body.The influence of the vertical dynamic interaction on the dynamic properties of the human-structure coupled system in the situation of single person and crowd were researched,and the influence of the parameters,such as the position of human,human-structure mass ratio and frequency ratio,the crowd density,to the dynamic interaction were also analyzed.Besides,a single person-structure dynamic interaction test was carried out to verify and complete the conclusions drew from the research work mentioned above.Secondly,with the mass-spring-damper model simulating the human body,the equation of motion of the crowd-floor-TMD coupled system was established.Based on the equation of motion,the efficiency of vibration reduction between STMD and MTMD were compared,and the influence of the human-structure mass ration on the efficiency was researched.Besides,the influence of the frequency of the structure and the dynamic interaction on the optimal parameters of the TMD was analyzed.Lastly,taking a large-span composite slab as the example of the large-span floor structure,adopting the load model suggested by IABSE(international association of bridge and structure engineering),the human-induced vibration and vibration serviceability evaluation were analyzed at different walking speed.Aiming at the fact that the human-induced vibration of the structure is excessive to the threshold of the criterion,the vibration reduction scheme was proposed.By means of numerical simulation,the scheme was verified and the expected effect was calculated.