Upload
jitheshks
View
218
Download
0
Embed Size (px)
Citation preview
8/13/2019 05.Smart Structure
1/23
R.MANOJ KUMAR
10 CMR 005
SMART STRCTURES
8/13/2019 05.Smart Structure
2/23
8/13/2019 05.Smart Structure
3/23
Data
Acquisition
Data
Transmission
The aim of thiscomponents is to
collect the requiredraw data neededfor an appropriatesensing andmonitoring of the
structure
The purpose of
this part is to
forwarded the raw
data to the local
and/or central
command and
control units.
8/13/2019 05.Smart Structure
4/23
Command and Control Unit
The role of this unit is to manage and
control the whole system by analyzing
the data, reaching the appropriate
conclusion, and determining the actionsrequired
8/13/2019 05.Smart Structure
5/23
Data
Instructions Action Devices
The function of this
part is to transmit the
decisions and the
associated instruction
back to the members
of the structure
The purpose of this
part is to take
actions by triggeringcontrolling
devices/units
8/13/2019 05.Smart Structure
6/23
Smart Structures
CONTROL
ACTUATIORSENSOR
DATA
INSTRUCTIONS
DATA
TRANSMISSION
8/13/2019 05.Smart Structure
7/23
Buildings and Bridges
Skyscrapers and long bridges are subject to
resonance created by high winds and seismic
activity
In order to mitigate the resonance effect, it is
important to build large dampers into theirdesign to interrupt the resonant waves
If these devices are not in place, buildings and
bridges can be shaken to the ground
8/13/2019 05.Smart Structure
8/23
Dampers
Dampers are used in machines that you
likely use every day, including car, bike
suspension systems
If you take a look the How suspensionsystems work, you'll learn that damping
systems use friction to absorb some of the
force from vibrations
A damping system in a building is muchlarger and is also designed to absorb the
violent shocks of an earthquake
The size of the dampers depends on the
size of the building
8/13/2019 05.Smart Structure
9/23
Dampening Systems
Passive
Requires no input power to operate
They are simple and generally low in cost
They are uncontrollable
Active
Require a great deal of power
They are fully controllable
8/13/2019 05.Smart Structure
10/23
Semi-Active Combines features of passive and active
damping.
They are fully controllable yet require little input
power
MR fluid dampers are semi-active devices
That can change their damping level by varying
the amount of current supplied to an internal
electromagnet that controls the flow of MR fluid.
8/13/2019 05.Smart Structure
11/23
A full-scale
MR fluid
damperthat is 1-
meter long
and weighs
250
kilograms.This one
damper
can exert
20 tons of
force on abuilding
8/13/2019 05.Smart Structure
12/23
Inside the MR fluid damper, an electromagnetic
coil is wrapped around three sections ofthe piston.
Approximately 5 liters of MR fluid is used to fillthe damper's main chamber.
During an earthquake, sensors attached to the
building will signal the computer to supply thedampers with an electrical charge.
This electrical charge then magnetizes the coil,turning the MR fluid from a liquid to a near-solid.
Now, the electromagnet will likely pulse as the
vibrations ripple through the building.
8/13/2019 05.Smart Structure
13/23
This vibration will cause the MR fluid to change
from liquid to solid thousands of times persecond, and may cause the temperature of the
fluid to rise.
A thermal expansion accumulator is fixed to
the top of the damper housing to allow for the
expansion of the fluid as it heats up. This accumulator prevents a dangerous rise in
pressure as the fluid expands.
8/13/2019 05.Smart Structure
14/23
Buildings equipped with MR fluid
dampers will mitigate vibrations during
an earthquake
8/13/2019 05.Smart Structure
15/23
Depending on the size of the building, there
could be an array of possibly hundreds of
dampers.
Each damper would sit on the floor and be
attached to the chevron braces that are welded
into a steel cross beam.As the building begins to shake, the dampers
would move back and forward to compensate for
the vibration of the shock.
When it's magnetized, the MR fluid increases the
amount of force that the dampers
8/13/2019 05.Smart Structure
16/23
What is MR fluid
MR fluid doesn't seem like such a revolutionary
substance.
It's a gray, oily liquid that's about three times
denser than water.
It's not too exciting at first glance, but MR fluid is
actually quite amazing to watch in action.
8/13/2019 05.Smart Structure
17/23
MR Fluid Composition
Carbonyl Iron Particles -20 to 40 percentof the fluid is made of these soft ironparticles that are just 3 to 5 micrometers in
diameter. A package of dry carbonyl ironparticles looks like black flour because theparticles are so fine.
A Carrier Liquid -The iron particles aresuspended in a liquid, usually hydrocarbonoil. Water is often used in demonstratingthe fluid.
8/13/2019 05.Smart Structure
18/23
MR FLUID
AFTER MAGNETIZED
8/13/2019 05.Smart Structure
19/23
Advantages
This structure cut downs a lot of material
cost incurred in using under reamed pile and
factor of safety.
India has 25% of area prone to earth quake.
This smart technology will help in saving alot of men and material.
The health monitoring of structures will help
in forecasting failure and will provide time for
rehabitation.
8/13/2019 05.Smart Structure
20/23
35% of deccan pleateau has black cottonsoil, the use of this technology can ensure
safe and economical construction over
there.
As the structure is constantly maintained theservice life increases and the need for repair
decreases.
8/13/2019 05.Smart Structure
21/23
Related Project
Mitigation of wind-rain-induced cable
vibration in cable-stayed bridges using
adjustable fluid dampers
Control of wind-rain-induced cable vibrationof Dongting Lake Bridge using magneto-
rheological dampers
Semi-active tuned liquid column dampers
using magneto rheological fluids forvibration control of tall buildings
8/13/2019 05.Smart Structure
22/23
Wind-rain-induced vibration control of
stay cables in the Dongting Lake Bridge
8/13/2019 05.Smart Structure
23/23
THANK YOU