Web crippling behaviour of cold-formed steel member with web openings

Rights statement
Awarding institution
  • University of Strathclyde
Date of award
  • 2012
Thesis identifier
  • T13122
Qualification Level
Qualification Name
Department, School or Faculty
  • Cold-formed steel sections are often used as wall studs or floor joists; such sections often include web holes for ease of installation of the services. Web crippling at points of concentrated, or localised, load or reaction in thin walled beams is well known to be a significant problem. Coldformed steel design codes, however, do not consider the effect of such web holes. In this thesis, a combination of experimental tests and non-linear elasto-plastic finite element analyses is used to investigate the effect of such holes on web crippling under two loading conditions interior-twoflange (ITF) and end-two-flange (ETF). The cases of both flange fastened and flange unfastened are considered. A good agreement between the experimental tests and finite element analyses is obtained in terms of both strength and failure modes. The finite element model is then used for the purpose of a parametric study on the effect of different sizes and position of holes in the web. It is demonstrated that the main factors influencing the web crippling strength are the ratio of the hole depth to the depth of the web, and the ratio of the distance from the edge of the bearing to the flat depth of web and the ratio of the length of bearing plates to the flat depth of the web. The web crippling strength without holes predicted from test and finite element analysis results are compared with the web crippling strength obtained from design codes. An extensive statistical analysis is carried out on web crippling strength of cold-formed steel sections with web holes. Design recommendations in the form of web crippling strength reduction factors are proposed, that are conservative to both the experimental and finite element results
Resource Type
Date Created
  • 2012
Former identifier
  • 946591