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Human-induced vibration is an important serviceability issue of modern structural designs, especially for light long-span structures. The common heel-drop impact is usually considered in evaluating the vibration of cold-formed steel (CFS) floors. This paper proposes a simplified equation for determining the peak accelerations under transient impacts, based on the Duhamel integral. The analytical results were validated with a comparison with the results from the heel-drop test results on a CFS floor of 3 900mm × 5 600mm (at both construction and completion stages). The dynamic responses of the floor, including peak acceleration, maximum transient vibration value (MTVV), and crest factor (a ratio of MTVV-to-peak acceleration) were analyzed in detail. The natural frequencies of the floor were obtained from the FFT and FRF analysis of heel-drop and hammering test results. The investigated on-site composite CFS floor with concrete topping was found to have a high fundamental frequency: 17Hz at the construction stage and 21Hz at the completion stage. In determining the fundamental frequency of the CFS floor, the hammering was thought to be more effective than the heel-drop owing to the phenomenon of human-structure interaction (HSI). Moreover, finite element analyses were performed to study the effects of profiled steel sheeting type (Types 28-100-800, 21-180-900, and 14-80-640) and concrete thickness (40, 50, 60, 70, 80, 90, and 100mm). With the SCSC condition (two opposite edges clamped and the other two edges simply-supported), the peak acceleration decreased by 50% when the concrete thickness increased from 40mm to 100mm.

A packaging system using the material of honeycomb paperboard, when it is subjected to drop impact, is a major concern to manufacturers as it relates to the maximum stress causing failure. In this work, the full-field dynamic responses of product packaging system are measured and analyzed in detail with the simulation and experiment method. First, on the basis of theoretical analysis, a series of honeycomb paperboards with different size dimension of paper honeycomb core had been set up in the FEA software. Then a packaging system which is made up of rigid body and deformable body had been analyzed. The results show that the physical dimension of paper honeycomb core has a great effect on its impact resistance: with the increasing size dimension, the peak acceleration has a quickly alteration within 10 mm–20 mm, but in other region it has an effect in the form of up and down fluctuation. At the same time, with the increasing size dimension, honeycomb paperboard can improve the energy absorption ability in the condition of elastic deformation. The research results can be used to optimize the structure design and material selection.

A theoretical attenuation model of earthquake-induced ground motion is presented and discussed. This model is related directly to physical quantities such as source and wave motion parameters. An attenuation formula for rms acceleration of ground motion is derived and verified using acceleration data from moderate-sized earthquakes recorded in Iceland from 1986 to 1997. The source parameters and the crustal attenuation are computed uniformly for the applied earthquake data. Furthermore, attenuation formulas for peak ground acceleration are put forward.