Abstract: The paper deals with the problems of the actual
behavior, failure mechanism and load-carrying capacity of the special
bolt connection developed and intended for the assembly connections
of truss main girders of perspective railway temporary steel bridges.
Within the framework of this problem solution, several types of
structural details of assembly joints have been considered as the
conceptual structural design. Based on the preliminary evaluation of
advantages or disadvantages of these ones, in principle two basic
structural configurations – so-called “tooth” and “splice-plate”
connections have been selected for the subsequent detailed
investigation. This investigation is mainly based on the experimental
verification of the actual behavior, strain and failure mechanism and
corresponding strength of the connection, and on its numerical
modeling using FEM. This paper is focused only on the cyclic
loading (fatigue) tests results of “splice-plate” connections and their
evaluation, which have already been finished. Simultaneously with
the fatigue tests, the static loading tests have been realized too, but
these ones, as well as FEM numerical modeling, are not the subject of
this paper.
Abstract: The paper deals with the diagnostics of steel roof
structure of the winter sports halls built in 1970 year. The necessity
of the diagnostics has been given by the requirement to the evaluation
design of this structure, which has been caused by the new situation
in the field of the loadings given by the validity of the European
Standards in the Czech Republic from 2010 year. Due to these
changes in the normative rules, in practice existing structures are
gradually subjected to the evaluation design and depending on its
results to the strengthening or reconstruction, respectively. Steel roof
is composed of plane truss main girders, purlins and bracings and the
roof structure is supported by two arch main girders with the span of
L = 84 m. The in situ diagnostics of the roof structure was oriented to
the following parts: (i) determination and evaluation of the actual
material properties of used steel and (ii) verification of the actual
dimensions of the structural members. For the solution the nondestructive
methods have been used for in situ measurement. For the
indicative determination of steel strengths the modified method based
on the determination of Rockwell’s hardness has been used. For the
verification of the member’s dimensions (thickness of hollow
sections) the ultrasound method has been used. This paper presents
the results obtained using these testing methods and their evaluation,
from the viewpoint of the usage for the subsequent static assessment
and design evaluation of the existing structure. For the comparison,
the examples of the similar evaluations realized for steel structures of
the stadiums in Olomouc and Jihlava cities are briefly illustrated, too.
Abstract: The paper presents the brief information on particular results of experimental study focused to the problems of behavior of structural plated components made of fiber-cement-based materials and used in building constructions, exposed to atmospheric physical effects given by the weather changes in the summer period. Weather changes represented namely by temperature and rain cause also the changes of the temperature and moisture of the investigated structural components. This can affect their static behavior that means stresses and deformations, which have been monitored as the main outputs of tests performed. Experimental verification is based on the simulation of the influence of temperature and rain using the defined procedure of warming and water sprinkling with respect to the corresponding weather conditions during summer period in the South Moravian region at the Czech Republic, for which the application of these structural components is mainly planned. Two types of components have been tested: (i) glass-fiber-concrete panels used for building façades and (ii) fiber-cement slabs used mainly for claddings, but also as a part of floor structures or lost shuttering, and so on.