الفهرس 
INTRODUCTION--,Only 14 pages are availabe for public view
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Abstract
This thesis is concerning with the static and dynamic analysis of bridge
girders. The thesis introduces an extensive survey of published work on
history, temperature effect, time-dependent analysis, and static and dynamic
analyses of bridges. Concrete cracking moment and ultimate strength are
determined in order to confirm the structure capacity against failure. The
interaction between concrete and reinforcing steel due to the tension stiffening
related with concrete cracking is also considered. Time-dependent analysis
models are studied with material properties and environmental conditions for
solving the phenomena of creep, shrinkage, concrete aging, and thermal effect.
Long-term effects originate from the time-dependent behaviour of concrete,
and from reinforcing steel, and prestressing steel. For concrete, both
mechanical strain due to loads, and non-mechanical strains due to creep,
shrinkage, concrete aging, and temperature effects are considered. For steel
reinforcement, temperature effects, are concerned with the calculation of axial
strain. For prestressing steel, it is regarded with tendon relaxation and
prestressing force losses due to friction, anchorage slip, and creep and
shrinkage of concrete with time.
Mathematical models for concrete box sections, and for cable elements
are introduced in details. A proposed procedure for the nonlinear static analysis
of prestressed box girder cable stayed bridges is also given.
A developed computer program considering long-term effects into an
advanced and updated time-dependent analysis is prepared based on the current
available bridge specifications and updated research results related to timedependent
effects. The test program includes 27 specimens. Parametric studies
on the effect of compression reinforcement, amount of the sustained loads, and
concrete compressive strength, on time-dependent behaviour were carried out.
Furthermore, the nonlinear dynamic analysis of prestressed box girder
cable-stayed bridges has been carried out. 10 addition, a comparative study on
three types of cable-stayed bridge has been performed A summary of the work carried out in the present thesis is presented
together with general conclusions and suggestions for future work.