The numerical simulation of wheel loads on an electric overhead travelling crane
Date
2007-12
Authors
McKenzie, Kim Anne
Journal Title
Journal ISSN
Volume Title
Publisher
Stellenbosch: University of Stellenbosch
Abstract
The failure rate of electric overhead travelling crane supporting structures across the world is
unacceptably high. Failures occur even when the supporting structures are designed within the
relevant design codes. This demonstrates a lack of understanding of the dynamic behaviour of
cranes in many design codes.
The current South African loading code is simplistic with respect to crane supporting structure
design, relying on empirical factors to determine the correct loads. While these factors lead to
predicted forces in the correct range of values, the Eurocode’s methods are more scientifically
based. In recognition of this the draft South African code predominantly incorporates the
methods used by the Eurocode to calculate design forces for crane supporting structures.
The purpose of this thesis was to use an existing numerical model to determine the wheel
loads induced by a crane into the crane supporting structure through hoisting, normal
longitudinal travel, skewing and rail misalignment. The numerically obtained forces were then
compared with the design forces estimated in the current South African code and the
Eurocode, in order to determine whether the factors and methods used in the codes are
accurate.
The current empirically based South African code was found to be highly conservative. In
contrast the scientifically based design forces from the Eurocode were close to the
numerically calculated forces, only failing to predict the behaviour of the crane in the case of
skewing. Further work needs to be completed in the estimation of forces induced during this
load case. Once this is achieved it is hoped that the better understanding of the crane forces
adapted from the Eurocode into the draft South African code will lead to a reduction in
failures of electric overhead travelling crane supporting structures.
Description
Thesis (MEng (Civil Engineering))--University of Stellenbosch, 2007.
Keywords
Theses -- Civil engineering, Dissertations -- Civil engineering