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.
Through the last centuries Scientists and Researchers have created analytic and
geographic multi-methods and formulas for the definition of elastic curve’s unknowns of
beams. We have seen that most of these methods had matched in their end formulas
, while
they only differed by the analytic basis for the differentiating of these formulas, that their
introductions depended on different physic expressions and mathematic relations. This
scientific work contains a concise preview for the definition relations and methods of
elastic Curve’s unknowns of beams available, so that the expression about these in an easy
and collective expression with agreement of the depended analytic method by the
Researcher. That can avail of the academic job on the first hand, and it helps the structural
analyzer choose the proper and easier device for his structural analysis for the definition of
elastic Curve’s unknowns of studied structural system.
This article summarizes a numerical and mathematical comparison between filled
and hollow X-shape plates to develop a new steel energy dissipative damper for structures
protection of earthquakes. The plate is a weld from two ends. Energy is dissipa
ted through
flexural yielding when the plate is subjected to inelastic cyclic deformation. The
performance of the plate was verified by five models by software ABAQUS and plastic
mechanism analysis. Results showed that the plate exhibited stable hysteresis and dissipate
energy with excellent values. It is Important to say all dimensions of plates and quality of
steel are verified by international articles. This article's interest lies in studying the effect
of openings on plate's dissipation energy.
