The precise control of the shape of transversely stiffened suspended
cable systems is crucial. However, existing form-finding methods primarily rely
on iterative calculations that treat loads as fixed known conditions. These
methods are inefficient and fail to accurately control shape results. In this
study, we propose a form-finding method that analyzes the load response of
models under different sag and stress
levels, taking into account the construction process. To analyze the
system, a structural finite element model was established in ANSYS, and
geometric nonlinear analysis was conducted using the Newton-Raphson method. The form-finding analysis
results demonstrate that the proposed
method achieves precise control of shape, with a maximum shape error
ranging from 0.33% to 0.98%. Furthermore, the relationships between loads and
tension forces are influenced by the deformed shape of the structures,
exhibiting significant geometric nonlinear characteristics. Meanwhile, the load
response analysis reveals that the stress level of the self-equilibrium state in the transversely stiffened suspended cable
system is primarily governed by strength criteria, while shape is
predominantly controlled by stiffness criteria. Importantly, by simulating the
initial tensioning process as an initial condition, this method solves for a
counterweight that satisfies the requirements and achieves a self-equilibrium
state with the desired shape. The shape of the self-equilibrium state is
precisely controlled by simulating the construction process. Overall, this work
presents a new method for analyzing the form-finding process of large-span
transversely stiffened suspended cable system, considering the construction
process which was often overlooked in previous studies.
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