Forensic Engineering Investigation and Analysis of a Tower Crane Collapse

Abstract

Tower cranes are popular and one of the predominant methods of material handling in high rise building construction. When there is a collapse of a tower crane in a city like New York, it is very visible, receives intense scrutiny, and becomes potentially political. This paper examines a 250-foot-tall tower crane collapse during the jumping phase of the crane to increase its height in support of a multi-level building construction. The author’s investigation examines the “defective sling” claim as the primary cause of the crane collapse along with some key findings and opinions regarding the slings used to rig the collar tie to the tower section of the crane.