The paper aims to study a concrete structure, currently used in civil engineering,
which has certain symmetries. This type of problem is common in engineering practice,
especially in civil engineering. There are many reasons why structures with identical
elements or certain symmetries are used in industry, related to economic considerations,
shortening the design time, for constructive, simplicity, cost or logistical reasons.
There are many reasons why the presence of symmetries has benefits for designers,
builders, and beneficiaries. In the end, the result of these benefits materializes
through short execution times and reduced costs. The paper studies the eigenvalue
and eigenmode properties of vibration for components of the constructions' structure,
often encountered in current practice. The identification of such properties allows
the simplification and easing of the effort necessary for the dynamic analysis of
such a structure.