On the influence of skewing forces upon the fatigue of a bridge cranestructure during travelling

Disertacija obrađuje problematiku praktičnog uvođenja opterećenja izazvanih zakošavanjem dizalice u normiranu proceduru dokaza zamorne čvrstoće njene noseće konstrukcije. U prvom delu rada koncizno je izložena teorijska podloga zakošavanja mosne dizalice, neophodna za potpunije razumevanje relevantnih obeležja predmeta istraživanja. Predložene su metode za eksperimentalnu determinaciju bočnih sila u interakciji točak – šina, odn. vodeća rolna – šina. Testiranje predloženih metoda spovedeno je kroz eksperimente na realnom objektu – jednogredoj električnoj mosnoj dizalici nosivosti 3,2 t i raspona 8,91 m. Komentarisani su reprezentativni rezultati i date su smernice za sprovođenje dokaza zamorne čvrstoće detalja noseće konstrukcije dizalice, uzimajući u obzir pri tom i spektre sila zakošenja. Takođe je ukazano i na neke nejasnoće i nedorečenosti u važećim standardima, a u vezi proračunskog određivanja sila zakošenja.The dissertation deals with the problem of practical application of loadings caused by crane skewing, in normative procedures of fatigue strength proof calculations of crane supporting structure. In the first part, the theoretical framework of bridge crane skewing, necessary for better understanding of relevant characteristics of the research topic, has been concisely elaborated. Methods are proposed for experimental determination of lateral forces in wheel/rail and guiding roller/rail contacts. These methods were tested through a series of experiments on a real object – an electrically driven single girder bridge crane with a capacity of 3.2 t, and span 8.91 m. Some representative measurement results are discussed and guidelines are given for performing the fatigue strength proof calculation of crane supporting structure details, taking into account skewing forces spectra, too. Also, attention has been drawn to certain unclear points and inconsistencies in norms in force, concerning calculative determination of skewing forces