ABSTRACT
ABSTRACT: There are a large variety of construction methods used during bridges erection; one of the most interesting, particularly when bridges have long spans or have to overpass deep valley or rivers, is the launching of the bridge from an abutment. The launching phase, generally, is an important phase but last relatively a very short time compared to the total service life of the structure; consequently it is necessary that an accurate preliminary analysis of the technical approach of the erection method statements is adopted. It is also relevant to carry out precise, complete and consistent calculations to understand more exactly the mechanisms that the might structure develop, during the erection phases, in order to assign minimal safety coefficients required by the codes in force or in the technical specifications prepared for this temporary condition. Herein some specific investigations are proposed in order to solve satisfactorily the difficult problems met during the bridge erection: patch loading is one of the latter. Briefly some experiences gained in bridge launching is discussed, focusing on interesting solutions of some practical aspects and on erection techniques, like pull launching of the bridge in a wide curved or long length spans, using special but suitably designed equipments with due account taken of the cost-benefit aspect, when choosing a solution amongst those that are technically practicable.
