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Knox, E.H., Van Bree, M.P., Kenner, M.T. and Wilkinson, J.A. (2009) Structural Stepladder Failure: Analysis of Root Cause. Proceedings of the ASME International Mechanical Engineering Congress and Exposition, 13-19 November 2009, Lake Buena Vista, 433-441.

has been cited by the following article:

• TITLE: Failure Analysis of an Aluminum Extension Portable Ladder

  AUTHORS: Abdel-Hakim Bouzid

  KEYWORDS: Portable Ladder, Beam Shortening, Columns Axially Restrained, Buckling

  JOURNAL NAME: Materials Sciences and Applications, Vol.5 No.9, July 31, 2014

  ABSTRACT: The conditions of end supports of straight ladders are often the cause of major injuries. The firm and secure ladder ends against instability in general and sliding of the top and bottom ends in particular are among the check list of most ladder safety training books and manuals. However, the restraint to the free expansion of a ladder can cause a catastrophic failure due to buckling even at intermediate loads and should be presented in the latter as a serious potential hazard. This paper deals with an investigation of an extension. An analytical structural model that simulates the buckling behavior of an axially restrained ladder subjected to static and dynamic loading is developed. It compares two different ladder end conditions and shows that instability due to buckling can occur during ascension or descent in the case of an axially restrained ladder. The analytical results are supported and validated by a finite element model simulation conducted in parallel. This study may explain the root cause of similar incidents involving falls from portable ladders worldwide.