It was recently noted that the costs of the
base metal alloy manufacturing have been increased, so some dental
laboratories have recasted the alloy many times although the company's
recommendations by using the alloy once. Therefore, this study aims to
investigate the effect of re-casting the Co- Cr alloy several times on
bridge bending.
Sandwich panels are locally produced with two faces of metal those which cover a
hard adhesive and thick core of polyurethane. The widely Extend of these panels increase
day for day as structural elements imitating the function necessities of the e
ngineering
construction.
The use of those panels as carried structural elements in wall or ceiling structures can
coincide with a submission of their sections materials, especially the two faces to the
change in a nature of the normal stress acted on them due to the alternate of the panel part
bending statically or dynamically when the alternate was produced from the change of
the loading acting direct on it or from the alternate of the live loading on the adjacent fields
of the continuous systems from it.
The evaluation of the sustain capacity and stability of the sandwich elements
consisted of such panels performs depended to the critical stress value leaded to arise of the
wrinkling waves of the compressive face of the panel that it values depended first on the
quality and properties of the production.
The research handled the testing of the sustainability and stability of the local
produced sandwich panel due to the alternate in a nature of it stress statically as a carried
structural element in the structural system built from such panels.
The conclusions of the research showed that this produced panel
follows a linear behavior too even in the case of the change of its bending direction or stress
nature of its face, especially in the loading steps coincided at least to the arising of the critical
wrinkling stress, whereas the value of this stress decreases 40% from its value for the
loading or bending case of the panel in only one direction.
The equipment of reinforced concrete by using native materials
(cement-aggregates-steel) in ideal conditions help us producing
concrete that consummate the Syrian Arab Code conditions, but
these are not found in Engineering Structure workshop that
have
affection of characters used materials in one hand, and these
behavior in the common work with steel –Structural behavior of
Engineering member espial in serviceability stage, that may be
expose accepted limits in other hand . So it is necessary to correct
the Syrian Arab Code's formulas of deformation and finding
suitable mathematical factors and formulas that insure structural
safety for reinforced concrete members under bending moment that casted in structure workshop circumstances in Syrian Arab
Republic.
