Network arch bridges are efficient structures which allow the construction of its main
structural elements in very slim dimensions. The advantages of the construction method
lie in an aesthetic appearance as well as in material savings. The decisive factor here
is the choice of the hanger arrangement as this has a considerable influence on the load-
bearing behaviour.
The purpose of the present work is the improvement of the arrangement of the hangers
using an optimization method. To achieve this, an optimization tool was developed. The
implementation of the program, including all sub-programs, such as the creation of the
calculation model, the FE-analysis, the optimization algorithm, and output of the results,
is done in Python.
At the beginning of the work, a general insight into the load bearing behaviour of the
network arch bridges and the loads acting on them is given. Following the necessary
theoretical bases of optimization and the chosen optimization method are explained. In
addition, the sub-programs of the optimization tool and the method by which they were
implemented are explained. To determine the most advantageous hanger arrangement,
four possible arrangements from the literature are subsequently optimized and compared
regarding specifically selected static criteria, such as the maximum axial force or
the maximum stress range in the hangers.
The result of this thesis is an optimization program which allows the user to optimize
the hanger arrangement of a network arch bridge based on different boundary conditions.
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