Impact Loads Produced by Human Motion. Part 2. Requirements for Structures and Methods of Test

摘要

Impact loads produced by human motion - walking, falling, jumping etc - exerted on lightweight and/or brittle structural components give rise to stresses of such intensity that special attention must be paid to their effects. These impact loads are significant in two different ways, firstly from the standpoint of the safety of the person performing the movement, and secondly from the standpoint of the structural performance such as permissible deformation, crack width, etc. Previously, fundamental knowledge of these effects was virtually non-existent. However, most of the movements which may occur in relation to building structures such as floors, walls, roofs, etc. were studied in Part 1 of this project and the results published in a report. In these tests, the forces caused by each motion pattern were recorded - their duration, the magnitude of the impact, etc. Different types of materials, representing building elements of varying stiffness and mass, were studied. This report presents a systematic subdivision into primary and secondary groups of building elements which are sensitive to such impact effects. An example of such grouping are roofs, subdivided into roofs which can be walked on, roofs which can be walked on with care, plastics domes and non-walkable roofs. For each group, requirements are given which take into account not only the effect of the load but also the frequency of occurrence of the motion and the consequences of a failure or some other damage to the construction. Details are also given of extensive calibration tests on test prototypes which make possible, for each group of structures, the specification of test models which are capable of reproducing the movements on which design is to be based.