Following the video surveillance and personal video cameras: New tools and innovations to health monitor the earthquake wave field

Abstract

Video cameras are becoming essential tools for obtaining real-time information on the mechanical performance of structures and their contents during seismic events as well as information on the moving properties of propagating media, such as tsunamis, landslides, and water sloshing. Their recorded images also provide important clues on human behavior during shaking. In this paper a large set of situations obtained from published YouTube videos, involving structures, natural outfits, human behavior are presented.Video cameras cannot replace laboratory static tests or tests on shaking tables, pseudo-dynamic sub-structure testing, wind tunnels or the channel propagation of waves. However, information that is collected over time and well used is of great value, as it shows the real world without any shortcomings provoked by “similarity laws”, “boundary conditions”, or a “friction and nonlinear hypothesis”. This information should be collected even if it only serves as an “inspiration” to researchers by supporting new ideas that only visualization can provide. This type of information can be considered a random visual health monitoring system.The present paper pretends to show the added value brought by video and personal cameras to the health monitoring of the wave field. We supplement the presented observations with practical recommendations supported in a simple analysis. Once treated, the images can be used in presentations to illustrate different phenomena related to the wave propagation and effects on the built environment and can also serve as an inspiration for mathematical modeling and/or can supply information that otherwise would be lost.