Experimental study on the damping property of aluminum alloy latticed shells with gusset joints

In order to investigate the damping property of aluminum alloy latticed shells with gusset joints, as well as to fill a blank in the existing design codes which do not give clear damping ratio value of this kind of structures, experimental tests were carried out on an aluminum alloy latticed shell with gusset joints. The structural dynamic responses were aroused by hammer impact, and were recorded by vibration sensors. The acceleration response frequency spectra at nodes were obtained through FFT method, and the structural damping ratio was calculated by half-power bandwidth method. In the experiments, the different strength of hummer impact, different locations of vibration sensors and different excitation places were considered, a total number of 57 test load cases were designed and executed, and a series of damping ratios were gotten from the experiments. A statistic study was carried out on the data given by the tests, then an average damping ratio was suggested for this kind of structures, that is, ξ=3.3%. A finite element model of the tested structure was established using the suggested damping ratio, and the nodal dynamic responses given by numerical analysis show good consistency with those given by the tests. It is demonstrated that the damping ratio given in the paper could serve the purpose of the dynamic response analysis and engineer design of aluminum alloy latticed shells with gusset joints.