The numerical simulation of wheel loads on an electric overhead travelling crane

[摘要] The failure rate of electric overhead travelling crane supporting structures across the world isunacceptably high. Failures occur even when the supporting structures are designed within therelevant design codes. This demonstrates a lack of understanding of the dynamic behaviour ofcranes in many design codes.The current South African loading code is simplistic with respect to crane supporting structuredesign, relying on empirical factors to determine the correct loads. While these factors lead topredicted forces in the correct range of values, the Eurocode's methods are more scientificallybased. In recognition of this the draft South African code predominantly incorporates themethods 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 wheelloads induced by a crane into the crane supporting structure through hoisting, normallongitudinal travel, skewing and rail misalignment. The numerically obtained forces were thencompared with the design forces estimated in the current South African code and theEurocode, in order to determine whether the factors and methods used in the codes areaccurate.The current empirically based South African code was found to be highly conservative. Incontrast the scientifically based design forces from the Eurocode were close to thenumerically calculated forces, only failing to predict the behaviour of the crane in the case ofskewing. Further work needs to be completed in the estimation of forces induced during thisload case. Once this is achieved it is hoped that the better understanding of the crane forcesadapted from the Eurocode into the draft South African code will lead to a reduction infailures of electric overhead travelling crane supporting structures.

[发布机构] Stellenbosch University