NDLI: Structural Stepladder Failure: Analysis of Root Cause

Content Provider	The American Society of Mechanical Engineers (ASME) Digital Collection
Author	Erick, H. Knox Michael, P. Van Bree Matthew, T. Kenner John, A. Wilkinson
Copyright Year	2009
Abstract	It is estimated that over 100,000 people each year are injured as a result of falls from ladders. Stepladders are one of the many different types of portable ladders, and are used frequently both on the job and around the home. Many times a fall from a stepladder is accompanied by a damaged ladder. In particular, one or both front side rails are often bent inward below the lowest step, and the lowest step buckled upward. This paper investigates the root cause of these types of structural failures through multiple analytical methods, including calculations, strain gage analysis, computer modeling, specialized strength and stability testing, and analysis of the user dynamics on the ladder. Results include data collected from various ladder makes (wood, aluminum, or fiberglass), sizes, and duty ratings (200 pounds, 225 pounds, 250 pounds, and 300 pounds). Additionally, the results were compared to the requirements of the existing ladder safety standards. The results demonstrate that the above described damage patterns do not occur when the ladder is upright on all four legs under normal use circumstances. Instead, the analyses conducted herein show that the damage results from the dynamic forces of the user impacting the ladder after the ladder has already substantially tipped over.
Starting Page	433
Ending Page	441
Page Count	9
File Format	PDF
ISBN	9780791843864
DOI	10.1115/IMECE2009-11551
e-ISBN	9780791838631
Volume Number	Volume 13: New Developments in Simulation Methods and Software for Engineering Applications; Safety Engineering, Risk Analysis and Reliability Methods; Transportation Systems
Conference Proceedings	ASME 2009 International Mechanical Engineering Congress and Exposition
Language	English
Publisher Date	2009-11-13
Publisher Place	Lake Buena Vista, Florida, USA
Access Restriction	Subscribed
Subject Keyword	Analytical methods Stability Computer simulation Aluminum Strain gages Glass reinforced plastics Rails Dynamics (mechanics) Structural failures Failure analysis Wood products Safety Damage Testing
Content Type	Text
Resource Type	Article

Sl.	Authority	Responsibilities	Communication Details
1	Ministry of Education (GoI), Department of Higher Education	Sanctioning Authority	https://www.education.gov.in/ict-initiatives
2	Indian Institute of Technology Kharagpur	Host Institute of the Project: The host institute of the project is responsible for providing infrastructure support and hosting the project	https://www.iitkgp.ac.in
3	National Digital Library of India Office, Indian Institute of Technology Kharagpur	The administrative and infrastructural headquarters of the project	Dr. B. Sutradhar bsutra@ndl.gov.in
4	Project PI / Joint PI	Principal Investigator and Joint Principal Investigators of the project	Dr. B. Sutradhar bsutra@ndl.gov.in Prof. Saswat Chakrabarti will be added soon
5	Website/Portal (Helpdesk)	Queries regarding NDLI and its services	support@ndl.gov.in
6	Contents and Copyright Issues	Queries related to content curation and copyright issues	content@ndl.gov.in
7	National Digital Library of India Club (NDLI Club)	Queries related to NDLI Club formation, support, user awareness program, seminar/symposium, collaboration, social media, promotion, and outreach	clubsupport@ndl.gov.in
8	Digital Preservation Centre (DPC)	Assistance with digitizing and archiving copyright-free printed books	dpc@ndl.gov.in
9	IDR Setup or Support	Queries related to establishment and support of Institutional Digital Repository (IDR) and IDR workshops	idr@ndl.gov.in