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Dynamic
response of reinforced concrete rectangular bunkers
under earthquake force
Indrajit
Chowdhury
Bunkers
and silos plays an important role in storing granular
materials in various industries, like power plants,
steel pants, oil and gas fields etc. For earthquake
analysis of such bunkers, the bunker and its contents
are usually considered as a lumped mass on which the
earthquake force acts and the inertial forces so generated
are transferred to the supporting frame. No methodology
exists to determine the dynamic pressure induced on
the wall due to the stored material which gets excited
at higher mode. In zone prone to moderate and strong
earthquake this force could induce significant effect
on the bunker wall. Present paper proposes a method,
based on which one can estimate such dynamic pressure
that could generate on the bunker walls and arrive
at a more realistic design.
Adjustments
simplified in mix design of concrete - A case study
with variability of aggregates
Krishan Juneja
When
the properties of the actual available aggregates
at site turn out to be different from those assumed
in the mix design, the original proportioning may
yield an uneconomical product. In such cases, instead
of redesigning, each time such differences crop up,
it is possible to achieve an economical and practical
design, either by the actual values of aggregate properties
such as surface area, fineness modulus and void content
of the components or by concept of equivalent mortar
volumes to yield satisfactory concrete properties.
Finite
element analysis of prestressed concrete beams considering
realistic cable profile and friction
Saleem Akhtar,
K.K.Pathak and S.S. Bhadauria
Prestressed
concrete is one of the most important engineering
materials, which is effectively used for tension as
well as compression loading. Because of the complex
nature of interaction between cable and concrete,
accurate analysis of stresses in prestressed concrete
structures is a challenge. The two important issues
in stress analysis are realistic cable modeling and
consideration of friction. In this study an innovative
approach has been developed to address these issues.
Cable profile is modeled as B-spline curve. A plane
stress Finite Element software has been developed.
Using the software various validation and new problems
are successfully analysed.
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