الخلاصة:
his study evaluates the seismic performance of steel frame with new type
of partially restrained connection using shape memory alloy (SMA).
superelastic form of shape memory alloy has large recoverable deformation
upon removal the load is used in current study. The suggested connection
consists of 16 steel bars and SMA bars (25.4mm) in diameter. 3D Finite
element simulation using ABAQUS v.2017 software is developed, and their
result was compared with an experimental test to validate the solution. This
study aims to explore the effect of integrated SMA bars within frame on
recentering ability, storey drift, residual storey drift, residual displacement,
Energy dissipation, peak floor acceleration, stress and residual stress in the
system.
Eleven steel frame (one storey frame with two damage factor (10, 100)
and two storey frame with three different combination of steel bars and
SMA bars) (100% steel bars, 50% steel bars and 50% SMA bars, 100%
SMA bars for each case), frame equipped with 100% steel bars was chosen
as reference model.
At the beginning of analysis, models were simulated under effect of free
vibration and shows the six Eigen modes and frequency for one storey and
two storey.
2
In case of one storey with damage factor =10 the addition SMA bars with
percentage is (50%, 100%) instead of steel bars which lead to decease the
residual roof displacement by (32.93%, 72%) respectively as compared
with reference model , which also lead to decrease the stresses and
residual stresses in frames.
While increasing earthquake intensity for one storey cases for frame
equipped with 50% SMA bars and 50% steel bars they enhance the
recentering ability with ratio (83.5%) as compared with reference model,
thus lead to reduction in residual displacement and residual storey drift by
(47.08%) as compared with reference model.
While in case of two storey frame , the results of numerical study shows
that the adding SMA bars in frame instead of steel bars with ratio of
(100%, 50%) improved strong recentering ability with the ratio (136%-
98%) respectively, as compared with reference model, in addition the
reduction in residual roof displacement is (158.72%, 82.7%) in case of
frame equipped with 100% SMA bars and frame equipped 50% SMA bars
and 50% steel bars respectively, as compared with reference model. Also
adding SMA bars instead of steel bars in frame lead to good contributes
towards reduces the stress and residual stress.
