الفهرس 
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Abstract
ABSTRACT
A new point of view for the number and the placement of semi-
active hydraulic dampers (SHDs) along the buildings associated with a
wireless sensor network and achieving high performance, is developed in
this dissertation. This proposed method depends on using a few number of
semi-active control devices distributed along the whole building but with
new placements instead of the uniform distribution of these devices in all
stories as traditional placement, which is considered very expensive and
complex especially in high-rise buildings. The method is termed; the
Proposed New Placement of SHDs. In addition, a design methodology for
this proposed method is suggested to simplify its applications. This
proposed design offers two different strategies for structural designers; to
obtain overall reduction in structural responses (strategy (A)) or to have
more reduction in floor displacements with smaller reduction in total base
shear (strategy (B)). The efficiency of Proposed New Placement of SHDs,
is examined firstly on the performances of low, medium, and high rise
buildings, and compared to the results of the traditional case, where the
SHDs and wireless sensing devices are distributed uniformly in all stories.
Secondly, it is examined under different earthquake intensities using more
realistic model has material nonlinearity.
The idea of this proposed placement was obtained after an extensive
study for the efficiency of traditional placement of semi-active control
devices in the first part of this dissertation. Several semi-actively
controlled structures were considered in this thesis gradually from one-
story to sixty-story buildings. These buildings are modeled and analyzed
using the finite element program ANSYS version 10. Semi-active control
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forces are derived according to the Linear Quadratic Regulator (LQR)
algorithm. However, to get control force for Proposed New Placement of
SHDs some adoptions are done on inputs of LQR algorithm to be
appropriated for this method. The MA TLAB control toolbox is used to
get the state feedback gain matrix of LQR algorithm which is used by
ANSYS for proposing finite element model for SHDs and wireless sensor
network using the control elements (COMBIN37). The accuracy of the
proposed finite element model is examined throughout a verification
problem from previous work. Three different earthquakes are used
throughout this research to cover wide variety of ground motion
characteristics and introduce acceptable results.
Several results and conclusions are obtained, which demonstrated
that the Proposed New Placement of SHDs method, using just a few
number of SHDs, provides better suppression performance of structural
vibration more than the traditional placement of SHDs. Moreover, when
material non linearity was considered in the analysis, this proposed method
not only gives the best reduction in responses but also prevents collapse of
the building under severe earthquakes, which occurs in uncontrolled and
traditional case of control with SHDs.
ID
forces are derived according to the Linear Quadratic Regulator (LQR)
algorithm. However, to get control force for Proposed New Placement of
SHDs some adoptions are done on inputs of LQR algorithm to be
appropriated for this method. The MA TLAB control toolbox is used to
get the state feedback gain matrix of LQR algorithm which is used by
ANSYS for proposing finite element model for SHDs and wireless sensor
network using the control elements (COMBIN37). The accuracy of the
proposed finite element model is examined throughout a verification
problem from previous work. Three different earthquakes are used
throughout this research to cover wide variety of ground motion
characteristics and introduce acceptable results.
Several results and conclusions are obtained, which demonstrated
that the Proposed New Placement of SHDs method, using just a few
number of SHDs, provides better suppression performance of structural
vibration more than the traditional placement of SHDs. Moreover, when
material non linearity was considered in the analysis, this proposed method
not only gives the best reduction in responses but also prevents collapse of
the building under severe earthquakes, which occurs in uncontrolled and
traditional case of control with SHDs.