SMART CONSTRUCTION MATERIAL
A SEMINAR REPORT
Submitted for Partial Fulfillment of the Requirement of the
Degree
of
BACHELOR OF TECHNOLOGY
In
CIVIL ENGINEERING
BY
MUZAFFAR ALI
(15EVGCE047)
Department of Civil Engineering
Vyas college of Engineering & Technology, Jodhpur
2018-2019
1
CANDIDATE’S DECLARATION
I hereby declare that the work ,which is being presented in this seminar entitled “SMART
CONSTRUCTION MATERIAL”, in the partial fulfillment for the award of the Degree of
“Bachelor of Technology” in the Department of Civil Engineering , vyas college of Engineering
& Technology, under Rajasthan Technical University is a record of my own work carried under
guidance ofProf. P.P Mathur Department of Civil
Engineering , Jodhpur Institute of
Engineering & Technology. I have not submitted the matter presented in this report anywhere for
the award of any other degree.
MUZAFFAR ALI
15EVGCE047
IV B.Tech VIII Sem, CE,VYAS
2
VYAS COLLEGE OF ENGINEERING & TECHNOLOGY
CERTIFICATE
This is to certify that the seminar report entitled “SMART CONSTRUCTION MATERIAL”,
being submitted for the partial fulfillment of the requirements of the Degree of “Bachelor of
Technology” in Civil Engineering of Jodhpur Institute of Engineering & Technology, Jodhpur is a
record of the seminar work carried out by MOHD ANWAR (15EJICE067) under my
supervision and guidance. Hehas not submitted the matter presented in this report anywhere for
the award of any other degree or diploma.
……………………
………………………
Prof. RAKESH CHOUDHARYProf. P.P.Mathur
ASST.PROF,
Department of CE,VYAS
Dr.ASHOKDHARIWAL
Head of Department
Civil Engg.
3
……………………
Principal
ACKNOWLEDGEMENT
The satisfaction and euphoria that accompany the successful completion of any task would be
incomplete without the mention of people who made it possible and whose constant guidance and
encouragement crowned our effort with success.
I profoundly thank Prof. P.P. MATHUR, Head of the Department of Civil Engineering who has
been an excellent guide and also a great source of inspiration to my work.
I would like to thank Mr RAKESH CHOUDHARY, assistant professor, civil engineering
department for his technical guidance, constant encouragement and support.
The satisfaction and excitement that accompany the successful completion of the task would be
great but incomplete without the mention of the people who made it possible with their constant
guidance and encouragement crowns all the efforts with success. In this context, I would like
thank all the other staff members, both teaching and non-teaching, who have extended their timely
help and eased my task.
Muzaffar Ali
Roll. No.- 15EVGCE047
B.TECH. VI YEAR
4
CONTENTS
PARTICULARS
PAGE NO.
CERTIFICATE
3
ACKNOWLEDGEMENT
4
CONTENTS
5
LIST OF FIGURES
7
ABSTRACT
8
CHAPTER 1 : INTRODUCTION: SMART MATERIAL
9
CHAPTER 2 : SMART MATERIAL : FOR SENSORS
12
2.1 Shape memory alloy
12
2.2 Optical fiber
13
2.3 Piezoelectric Materials
16
CHAPTER 3:SMART MATERIAL:: SUPER PERFORMING
17
MATERIAL
3.1. Advancements in Concrete
17
3.1.1 High Performance Concrete
17
5
3.1.2 Light Transmitting Concrete
18
3.1.3 Pervious Concrete
19
3.1.4 Aerated Concrete
19
3.1.5 Floating Concrete
20
3.2. Foamed Aluminum
21
3.3. Super Black
21
3.4. Woven Stainless steel
22
3.5. Creative Weave Metal Mesh
22
3.6. Aerogel
23
3.7. Laminated Thermo Plastic Panels
24
3.8. Banner works
25
3.9. Tension Fabric Structure
25
3.10. Other Super Performing Multi Purposed Material
26
CHAPTER 4 :APPLICATIONS OF SMART MATERIALS
27
CHAPTER 5 : CONCLUSION
32
REFERENCES
34
6
LIST OF FIGURES
Figure
Title
Page no.
1.1
Classification of smart materials
10
2.1
SMA deformation and cooling
12
2.2
SMA deformation and cooling Graph
13
2.3
Optical fiber in beam
14
2.4
Optical fiber in bridge
15
2.5
Piezoelectric Materials created electric field
16
3.1
High Performance Concrete
18
3.2
Light Transmitting Concrete
18
3.3
Pervious Concrete
19
3.4
Aerated Concrete
20
3.5
Floating Concrete with its application
20
3.6
Foamed Aluminum as decorative material
21
3.7
Mesh as false ceiling
22
3.8
Aerogel as insulator
23
3.9
Laminated Thermo Plastic Panels structure and application
24
3.10
Tension Fabric Structure
25
3.11
Corrugated glass and Fly-Ash concrete
26
7
Abstract
The seminar deals with an introduction and implementation of Smart material use for sensors,
Automated machines and super performing building materials and techniques all in terms of
energy saving efficiency of the material, cost efficiency, application feasibility, availability,
vernacular characteristics, life span, etc. A material is considered smart only when it contributes
something to upgrade the quality of building. With all those advancements in construction
techniques and also with the demand of end users for the smart buildings we as constructors and
designers are ought to introduce
something new and smart to fulfill their demands and needs. Smart structures and material
technologies are a tool for sharing the knowledge of how various building materials can
significantly increase production and profit using advanced communication, collaboration and
management technologies. The seminar provides an overview of the types of materials available
giving a new insight into innovative methods and techniques that will be available, and
open new doors for advancement and improvement in the construction industry. The new
materials discussed in this seminar present a small fraction of the options that are available for use
by industry.
8
CHAPTER 1
Introduction :Smart material
There is an increasing awareness of the benefits to be derived from the development and
exploitation of smart materials and structures in applications ranging from hydrospace to
aerospace. With the ability to respond autonomously to changes in their environment, smart
systems can offer a simplified approach to the control of various material and system
characteristics such as light transmission, viscosity, strain, noise and vibration etc. depending on
the smart materials used . There are a number of materials that act as both sensors and actuators
that can monitor and respond to their environment. However, with the ability to also modify their
properties in response to an environmental change, they can be 'very smart' and, in effect, learn.
While the scope of sensors and actuators is quite broad, three main sub-programs have been
identified – Smart Structures and Materials, Miniature Sensor and Actuators and Automated
Testing, Inspection Monitoring and Evaluation.
To understand all how and about of super performing construction materials we must study
materials according to their use from very root to tip. By that way we can easily conclude and
infer about the application, implementation and feasibility of that particular construction material.
Elements of construction where these smart materials and techniques shall be implemented
are:Foundation, Plinth, Beam, Column,Wall, Sill, Window, Door, Roof, Parapet, Skylights, Finish
works.Construction materials are said to be super performing when they Save overall building
energy, Make building esthetically pleasing, Cut cost of construction, Easily available, Increase
life span of building, Upgrade building quality, Make the building safe for living.
9
Smart Materials are materials that respond to environmental stimuli, such as temperature,
moisture, pH, or electric and magnetic fields. For example, photochromic materials that change
colour in response to light; shape memory alloys and polymers which change/recover their shape
in response to heat and electro- and magnetorheological fluids that change viscosity in response to
electric or magnetic stimuli. Smart Materials can be used directly to make smart systems or
structures or embedded in structures whose inherent properties can be changed to meet high
value-added performance needs. Smart Materials technology is relatively new to the economy and
has a strong innovative content. According to work by the Materials Foresight Panel, the use of
smart materials could make a significant impact in many market sectors. In the food industry,
smart labels and tags could be used in the implementation of traceability protocols to improve
food quality and safety e.g. using thermo chromic ink to monitor temperature history. In
construction, smart materials and systems could be used in 'smart' buildings, for environmental
control, security and structural health monitoring e.g. strain measurement in bridges using
embedded fibre optic sensors that can feel pain withfiber optic nerve systems.
Magneto-rheological fluids have been used to damp cable-stayed bridges and reduce the effects of
earthquakes. In aerospace, smart materials could find applications in 'smart wings', health and
usage monitoring systems (HUMS), and active vibration control in helicopter blades. In marine
and rail transport, possibilities include strain monitoring using embedded fibre optic sensors.
Smart textiles are also finding applications in sportswear that could be developed for everyday
wear and for health and safety purposes.
Fig. 1.1 Classification of smart materials
10
A. Structural Health Monitoring
Virtual human robots can be equipped with sensors, memory, perception, and behavioral
motor. This eventually makes these virtual human robots to act or react to events.

Also called Damage Detection

Using response signals to determine if there has been a change in the system's parameters.

Mathematically very much like parameter identification in many respects

Numerous methods have been proposed.

Impact is high for SMH systems that work without taking the base system out of operation.
B. Smart Structures
Key areas of focus for the development of smart structures to include: Miniaturisation and
integration of components, e.g. application of sensors or smart materials in components
Robustness of the smart system, e.g.interfacial issues relating to external connections to smart
structures Device fabrication and manufacturability, e.g. Electrorheological fluids in active
suspension systems, applications in telematics and traffic management Structural health
monitoring, control and lifetime extension (including self-repair) of structures operating in hostile
environments, e.g. vibration control in Aerospace and Construction applications. Thermal
management of high temperature turbines for power generation. Selfmonitoring, self-repairing,
low maintenance structures, e.g. bridges and rail track Smart structures that can self-monitor
internal stresses, strains, creep, corrosion and wear would deliver significant benefits. Projects can
be based on any material format (e.g. speciality polymers, fibres and textiles, coatings, adhesives,
composites, metals, and inorganic materials), which incorporate sensors or active functional
materials such as: piezoelectrics, photochromics, thermochromics, electro and magneto
rheological fluids, shape memory alloys, aeroelastictailored and other auxetic materials. For the
modelling of actor behaviors, the ultimate objective is to build intelligent autonomous virtual
humans with adaptation, perception and memory. These virtual humans should be able to act
freely and emotionally. They should be conscious and unpredictable. But can we expect in the
near future to represent in the computer the concepts of behavior, intelligence, autonomy,
adaptation, perception, memory, freedom, emotion, consciousness, and unpredictability
11
CHAPTER 2
Smart material: For sensors
SHAPE MEMORY ALLOYS
A shape memory alloy (SMA, smart metal, memory metal, memory alloy, muscle wire, smart
alloy) is an alloy that "remembers" its original, cold‐forged shape: returning the pre‐ deformed
shape by heating. This material is a lightweight, solid‐state alternative to conventional actuators
such as hydraulic, pneumatic, and motor‐based systems. Shape memory alloys have applications
in industries including medical and aerospace.
The three main types of shape memory alloys are the copper-zincaluminium-nickel, copperaluminium-nickel, and nickel-titanium (NiTi) alloys but SMA's can also be created by alloying
zinc, copper, gold, and iron.
Fig. 2.1 SMA deformation and cooling
The main property of SMA is Pseudo‐Elasticity described below
• One of the commercial uses of shape memory alloy involves using the pseudo‐elastic properties
of the metal during the high temperature (austenitic) phase. The frames of reading glasses have
been made of shape memory alloy as they can undergo large deformations in their high
temperature state and then instantly revert back to their original shape when the stress is removed.
This is the result of pseudoelasticity; the martensitic phase is generated by stressing the metal in
12
the austenitic state and this martensite phase is capable of large strains. With the removal of the
load, the martensite transforms back into the austenite phase and resumes its original shape.
• This allows the metal to be bent, twisted and pulled, before reforming its shape when released.
This means the frames of shape memory alloy glasses are claimed to be "nearly indestructible"
because it appears no amount of bending results in permanent plastic deformation.
Fig. 2.1 SMA deformation and cooling Graph
OPTICAL FIBER
An optical fiber is a flexible, transparent fiber made by drawing glass (silica) or plastic to a
diameter slightly thicker than that of a human hair. Optical fibers are used most often as a means
to transmit light between the two ends of the fiber and find wide usage in fiber-optic
communications,
where
they
permit
transmission
over
longer
distances
and
at
higher bandwidths (data rates) than electrical cables. Fibers are used instead of metal wires
because signals travel along them with less loss; in addition, fibers are immune to electromagnetic
interference, a problem from which metal wires suffer excessively. Fibers are also used
for illumination and imaging, and are often wrapped in bundles so they may be used to carry light
into, or images out of confined spaces, as in the case of a fiberscope. Specially designed fibers are
13
also used for a variety of other applications, some of them being fiber optic sensors and fiber
lasers.
Optical fibers typically include a core surrounded by a transparent cladding material with a
lower index of refraction. Light is kept in the core by the phenomenon of total internal
reflection which causes the fiber to act as a waveguide. Fibers that support many propagation
paths or transverse modes are called multi-mode fibers, while those that support a single mode are
called single-mode fibers (SMF). Multi-mode fibers generally have a wider core diameterand are
used for short-distance communication links and for applications where high power must be
transmitted. Single-mode fibers are used for most communication links longer than 1,000 meters
(3,300 ft).
Fig. 2.3 Optical fiber in beam
Fibers have many uses in remote sensing. In some applications, the sensor is itself an optical fiber.
Inother cases, fiber is used to connect a non-fiberoptic sensor to a measurement system.
Depending on the application, fiber may be used because of its small size, or the fact that
no electrical power is needed at the remote location, or because many sensors can
be multiplexed along the length of a fiber by using different wavelengths of light for each sensor,
or by sensing the time delay as light passes along the fiber through each sensor. Time delay can be
determined using a device such as an optical time-domain reflectometer.
14
Optical fibers can be used as sensors to measure strain, temperature, pressure, and other quantities
by modifying a fiber so that the property to measure modulates
the intensity, phase, polarization, wavelength, or transit time of light in the fiber. Sensors that vary
the intensity of light are the simplest, since only a simple source and detector are required. A
particularly useful feature of such fiber optic sensors is that they can, if required, provide
distributed sensing over distances of up to one meter. In contrast, highly localized measurements
can be provided by integrating miniaturized sensing elements with the tip of the fiber. These can
be implemented by various micro- and nanofabrication technologies, such that they do not exceed
the microscopic boundary of the fiber tip, allowing such applications as insertion into blood
vessels via hypodermic needle.
Fig. 2.4 Optical fiber in bridge
15
Piezoelectric Materials
Piezoelectric materials have two unique properties which are interrelated. When a piezoelectric
material is deformed, it gives off a small but measurable electrical material it experiences a
significant increase in size (up to a 4% change in volume)
Fig. 2.4 Piezoelectric Materials created electric field
Piezoelectric materials are most widely used as sensors in different environments. They are often
used to measure fluid compositions, fluid density, fluid viscosity, or the force of an impact. An
example of a piezoelectric material in everyday life is the airbag sensor in your car. The material
senses the force of an impact on the car and sends and electric charge deploying the airbag.
16
CHAPTER 3
SMART MATERIAL:: Super Performing Materials

Save overall building energy
Make building esthetically pleasing
Cut cost of construction
Easily available
Increase life span of building
Upgrade building quality
Make the building safe for living
Make building esthetically pleasing
Cut cost of construction
Easily available
Increase life span of building
Upgrade building quality
Make the building safe for living
1.Advancements in Concrete
1.1 High Performance Concrete
Lafarge has developed a whole new family of concretes called Ductal. These concretes
have high compressive and flexural strength, and their specialcharacteristics enable the
achievement of outstanding architectural feats. Ductal concrete incorporates strengthening
fibers and opens the horizon to ultra-high performance due to its special composition which
provides it with outstanding strength, six to eight times greater than traditional concrete
(under compression).“Fiber-reinforced” means that it contains metal fibers which make it a
ductile material. Highly resistant to bending, its great flexural strength means it can
withstand significant transformations without breaking. Ductal also comes with organic fibers for
applications with less load and for advanced architectural applications.
17
Fig 3.1 High Performance Concrete
1.2 Light Transmitting Concrete
The days of dull, grey concrete could be about to end. A Hungarian architect has combined
the world’s most popular building material with optical fiber from Schott to create a new
type of concrete that transmits light. A wall made of “LitraCon” allegedly has the strength of
traditional concrete but thanks to an embedded array of glass fibers can display a view of the
outside world, such as the silhouette of a tree, for example. “Thousands of optical glass fibers
form a matrix and run parallel to each other between the two main surfaces of every block,”
explained its inventor Áron Losonczi. “Shadows on the lighter side will appear with sharp
outlines on the darker one. Even the colours remain the same. This special effect creates the
general impression that the thickness and weight of a concrete wall will disappear.” The hope is
that the new material will transform the interior appearance of concrete buildings by
making them feel light and airy rather than dark and heavy.
Fig. 3.2 Light Transmitting Concrete
18
1.3 Pervious Concrete
The product that has a porous structure
which allows rainwater to pass directly through
the pavement and into the soil naturally. This
porosity is achieved without compromising
the strength, durability, or integrity of the
concrete structure itself. The pavement is
comprised of a special blend of Portland cement,
coarse aggregate rock, and water. Once dried, \the pavement has a porous texture that allows
water to drain through it at the rate of 8 to 12 gallons per minute per square foot. Tests
conclude that a square foot of Bahia sod drains at the rate of 2 1/2 to 3 gallons per minute.
According to the manufacturer, this rapid flow-through ratio inspired the phrase “the pavement
that drinks water.”
Fig. 3.3 Pervious Concrete
1.4 Aerated Concrete
It was discovered in 1914 in Sweden that adding aluminum powder to cement, lime, water,
and finely ground sand caused the mixture to expand dramatically. The Swedes allowed this
“foamed” concrete to harden in a mold, and then they cured it in a pressurized steam chamber-an autoclave. Autoclaved aerated concrete is produced by about 200 plants in 35 countries
and is used extensively in residential, commercial, and industrial buildings. At a density of
roughly one-fifth that of conventional concrete and a compressive strength of about one
19
tenth, AAC is used in load-bearing walls only in low-rise buildings. In high-rises, AAC is used in
partition and curtain walls
Fig. 3.4 Aerated Concrete
1.5 Floating Concrete
By replacing sand and gravel with tiny polymeric spheres, University of Washington materials
scientists have created a concrete stronger than traditional concrete but so light it floats in
water. The team won the regional American Society of Civil Engineers Concrete Canoe
Competition last year.
Fig. 3.5 Floating Concrete with its application
20
2. Foamed Aluminum
“Light-as-air, stronger-than-steel materials are just
beginning to shape our world. Foamed aluminum first
emerged from the lab in the frame of a 1998 Karman
concept car. Ten times stronger than traditional
aluminum at just one tenth the weight, the material
allows a more fuel-efficient
vehicle. Its isotropic cellular
structure helps the frame absorb
shock and serves as an insulating
firewall between the engine and
the rest of the car. The foaming
process can also be applied to
steel, lead, tin, and zinc.”The
product is a high strength,
extremely light weight material
that possesses high durability,
excellent finish and lasting value.
Fig. 3.6 Foamed Aluminum as decorative material
The foam comes in an assortment of densities and sizes up to five feet wide and up to fifty feet
long. It has numerous applications including architectural, automotive, marine, military, aviation,
transportation, electronics, appliances, and signage.
3. Super Black
British scientists have invented the darkest material on Earth. The super-black coating was
developed by researchers at the National Physical Laboratory in London. It could
revolutionize optical instruments because it reflects 10 to 20 times less light than the black
paint currently used to reduce unwanted reflections. The key to the nickel and phosphorous
coating’s blackness is that its surface is pitted with microscopic craters. “Super-black” is
especially effective at absorbing light which hits it at an angle. With the light source at right
angles, the coating reflects less than 0.35%. Black paint reflects about 2.5% - seven times more.
21
4. Woven Stainless steel
K5 New York is now offering woven stainless
steel in 18 different weaves, produced in
Switzerland by G. Bopp. This product has been
used in projects as diverse as railing systems and
furniture components. Custom weaves and
patterns are also possible.
5. Creative Weave Metal Mesh
Metal meshes have been known as decorative and functional design elements in architecture for
only a few years. During the continuous product development along with ordinary use such
as an fence element it became clear that metal meshes also have considerable technical
advantages which are extremely
relevant in the field of architecture.
Today, the architect has a wide range
of mesh samples at hand, with weaving
widths up to eight meters, which allow
for great design flexibility. Woven
metallic meshes used as partition
elements convey a new dimension to
any space. They can be used as
projection screens, and, taking into account their acoustic characteristics, are suitable for
the use in public buildings, opera houses and concert halls.
Fig. 3.7 Mesh as false ceiling
22
6. Aerogel
Aerogel or “Air glass” is a transparent material that looks like glass, insulates better than
mineral wool and is more heat resistant than aluminum. The material has many interesting
properties and possible applications such as insulation in windows and solar collectors, windows
in firewalls, a component in air-conditioning equipment, etc. Aerogel is molded, giving the
possibility of getting different shapes: cylinders, cubes, plates of varying thickness etc.
Chemically, Aerogel is composed of quartz and a great deal of air, making it fragile. The
grains of quartz are small compared to the wavelength of light, giving Aerogel good
transparency properties. At around 750°C (1380°F), it starts to shrink and slowly collapses to a
piece of ordinary quartz. Aerogel can be cut with aband saw and holes can be drilled with a metal
drill. It should be noted that Aerogel is non-flammable and non-toxic.
Fig. 3.8 Aerogel as insulator
23
7. Laminated Thermo Plastic Panels
Blizzard Composite GmbH manufactures high-tech plastic composites for the architectural
field as well as the trucking industry. Their core expanding machinery heats up and vertically
expands solid thermoplastic sheets, which are then processed into sandwich panels by
lamination equipment. Due to the unique geometry of the Pep Core, the panels are of low weight
and provide an excellent combination of high stiffness and compressive strength.
Fig. 3.9 Laminated Thermo Plastic Panels structure and application
24
8. Banner works
Koryn Rolstad is a Seattle-based industrial artist who leads an integrated team of industrial
designers, graphic designers, project managers and production staff in creating large-scale
aerial sculptures and public art installations around the world. Known as “Banner works,” her
pieces dexterously cross the boundaries between sculpture and signage, art and engineering.
9. Tension Fabric Structure
“Transform
it’s”
provocative
tension
fabric structures
are
appropriate
for
use
in
entertainment venues, special events, exhibits & trade shows, oranywhere that fabric
architecture is appropriate. Made of nylon spandex, the structures offer a viable surface for any
type of projection or lighting display, including front and rear projected video. It is also
possible to print on the fabric via silk-screening or dye sublimation digital printing.
Fig. 3.10. Tension Fabric Structure
25
10. Other Super Performing Multi Purposed Material

Geoweb: Cellular confinement system for vertical vegetation for green walls.

Aero formed aluminium:Tightly corrugated aluminum sheets as in bamboo mats.

Flexible Framing Track : For flexible outlining and fencing. A fence framed in metallic
frame.

Corrugated Glass: For inside esthetics and thermal insulation.

Plasphalt:Plastic blended with asphalt on roads for waste management.

Fly-Ash Concrete:Using Fly-ash residue as strengthening material with cement.
Fig. 3.11 Corrugated glass and Fly-Ash concrete
26
CHAPTER 4
Applications of Smart Materials
As described, smart materials have increasingly been used in many engineering fields. In this
part, some innovative applications in civil engineering are summarized as follows.
Seismic Rehabilitation of Bridges
Seismic damping devices were built with shape memory alloys that can be applied to retrofit
bridges. By concentrating energy dissipation in controlled locations, these devices can be used
to reduce the demand on individual frames in a multi-frame bridge, thereby enhancing the
performance of these structures.
Optimization of Smart Material Properties:
The work was carried out in several steps. The first step is to evaluate the effects of thermomechanical processing on the characteristics of Nitinol bars and the evaluation of effects of
the bar diameter, loading frequency and temperature on the characteristics of Nitinol bars
undergoing tension and compression cycles. Studies show that the effect of load frequency,
within the range expected for seismic applications, is small. The ambient temperature has little
effect on damping characteristics. Comparing the energy dissipated and the residual strain in
the samples, it is found that annealing a temperature of 350°C is the optimal temperature for
all four cases. The energy dissipated per unit mass of material was greatest for the samples at
27
350°C. The sample treated at 450°C had by far the worst performance in terms of energy
dissipation. Another parameter, which is important in the structure as well as reduced energy
dissipation capacity for applications in seismic mitigation, is the residual strain in the smart
material bar. Ideally, the sample should have very small residual strains after repeated cycles.
Large residual strains lead to large displacements. Results also showed that the samples
treated at 350°C have the smallest residual strain.
It was believed that the lack of information on large section behavior of smart materials is a
fundamental reason that smart materials have not been implemented in structures as seismic
dampers. It is generally thought that large section rods do not exhibit the same energy
dissipating characteristics as smaller sections, although few studies exist to quantify this
assumption. Full-scale smart material restrainer is tested, which consists of a 305 mm long,
25.4 mm diameter Nitinol shape memory alloy bar. The smart material bars are fully annealed
and 25% cold-worked. The samples are threaded at the ends and vacuum annealed at 450°C
for 60 minutes, followed by water quenching. The test suggested that the 50 nearly perfect
superelastic behavior could be obtained when the bars are properly heattreated. This leads to
the potential application of using smart materials as dampers in largescale structures, like
bridges.
Application of Smart Material Restrainers to Multi-Span Bridges:
Unseating of simple spans and frames has been a major problem for bridges in recent
earthquakes such as the 1989 Loma Prieta, 1994 Northridge, 1995 Kobe and 1999 Taiwan
earthquakes. The relative displacement of multiple-span simple supported bridges at the
hinges and abutments can result in collapse of the bridge if it exceeds the allowable
displacement. The use of smart material restrainers can provide a more effective alternative
for limiting relative hinge displacement than traditional cable restrainers. It also provides
sufficient stiffness and damping to limit the relative hinge displacements below a predetermined value. Analytical studies of typical bridges with the smart material restrainers
were conducted to evaluate the effectives of the smart material restrainers in limiting the
relative displacement of the hinges in bridge decks. With experimental results from step one,
nonlinear analytical models of the bridges are developed. Strong ground motions are used to
simulate the effects of the smart material restrainers on the response of the bridge. The
comparison between the smart material restrainer and commonly used steel restrainer cables
was made. For the bridge subjected to El Centro ground motion record, the adoption of
traditional restrainer may reduce the relative displacement to 24%, while smart material based
28
restrainer can reduce it up to 42%. There are several reasons to achieve such performance: the
restrainer is superelastic and they have the ability to maintain their effective stiffness for
repeated cycles. Another reason for that smart material restrainers are effective in limiting the
relative displacement of the bridge deck is believed to be the energy dissipation by the
restrainers. The comparison shows the energy dissipated by the smart material restrainers are
15% more than the traditional cables.
Repair and Strengthening of Concrete Structures
Structural deficiencies of bridges caused by damaging load and environmental effects, faulty
design practices or increased traffic loads represent a major problem with the US
transportation infrastructure. The shape memory-based rehabilitation system promises to
provide a rapid, efficient and low-cost approach with high levels of safety and reliability for
the rehabilitation of deficient bridge structures. The idea here relies on the restrained recovery
of shape memory alloys to rehabilitate and strengthen existing bridge structures. Shape
memory rods are pre-elongated in the Martensitic phase and then anchored onto the deficient
structural system; upon electrical resistance heating and transformation to the 51 Austenitic
phase. The constraints of shape recovery cause corrective (post-tensioning) forces to the
structure. It was believed that such approach has the following virtues over conventional
approaches: (a) ease and expedience of implementation (electrical resistance heating of shape
memory rods can be accomplished using an electrical generator); (b) reduced loss of posttensioning force because of such effects as slip and elastic deformations (strain far greater
than normal elastic strain of steel or composites can be recovered by the shape memory
effect); and (c) retention to correct future damages to the structure (damaging effects would
elongate the shape memory rods and such elongations could be recovered simply by electrical
resistance heating of the rods). To reduce the cost of unit weight, of smart materials, ironbased shape memory alloys have been developed. Using the iron-based shape memory alloys
provides an efficient and convenient means for rapid repair and strengthening of damaged or
deficient infrastructure elements. Restraints of shape recovery in these alloys can transfer
corrective (posttensioning) forces to structural systems. The process involves pre-elongation
of shape memory rods at ambient temperature, anchorage of pre-elongated rods onto the
structural system, and electrical resistance heating (using a common generator) of rods to
cause shape recovery and thus apply corrective forces to the structure. Application of the
corrective forces by shape memory rods is a versatile approach capable of tackling diverse
structural repair and strengthening problems. Laboratory and field tests verified the approach
in applications involving repair of flexural and shear damage in reinforced concrete beams.
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Smart Prestressing with Shape Memory Alloy
It is possible to obtain two-way shape-memory effect by an extensive thermomechanical
cycling. This involves heating the alloy above Af while it is constrained, and subsequent
cooling to below Mf , for several cycles. The resulting two-way shapememory material can
undergo large and opposite deformations under heating and cooling for several cycles, and can
serve as a two-way actuator. Using this two-way effect, one can apply and remove stress in a
structure, which can lead to a smart bridge, where the amount of prestress can be adjusted on
an as-needed basis. This research confirmed the ability of shape-memory wires to transfer
stresses to a concrete beam. The magnitudes of these stresses are above the yield stress of the
alloy and are well in excess of what is needed to crack the beam. It was found that strands
were well bonded by developing mechanical interlock in between the wires. Inadequate
concrete cover to the strands caused spalling at the end of the beams. Cracking observed at the
end of the beams was verified with acoustic emission source locations. Those experiments
demonstrate 52 the possibility of using this smart material in addition to regular prestressing
steel to offset prestress losses after prolonged use or to increase the capacity of an existing
bridge.
Applications of Fiber Optic Sensors:
The application of Fiber optic sensors in Civil Engineering may be as follows:
a) Physical Properties such as measurement of strain, displacement, temperature, wind
pressure and velocity in structures of any shape or size.
b) As real time detection tool to monitor the health of structure.
c) Monitoring of Concrete in bridges for cracks, long term deformations viz. creep and
shrinkage, corrosion of steel, evaluation of seismic damages etc.
d) In dams fiber optic sensors can be used to monitor expansion of joints, leakage, temperature
etc. e) In Heritage structures to examine the crack openings, Displacement monitoring, post
seismic damages etc.
Substitute for steel
It is reported that the fatigue behavior of CuZnAlSMA’s is comparable with steel. If larger
diameter rods can be manufactured. It has a potential for use in civil engineering applications. Use
of fiber reinforced plastics with SMA reinforcements requires future experimental investigations.
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Carbon fiber reinforced concrete
Its ability to conduct electricity and most importantly, capacity to change its conductivity with
mechanical stress makes a promising material for smart structures .It is evolved as a part of DRC
technology (Densified Reinforced Composites).The high density coupled with a choice of fibers
ranging from stainless steel to chopped carbon and Kevlar, applied under high pressure gives the
product with outstanding qualities as per DRC technology. This technology makes it possible to
produce surfaces with strength and durability superior to metals and plastics.
Smart concrete
A mere addition of 0.5%specially treated carbon fibers enables the increase of electrical
conductivity of concrete. Putting a load on this concrete reduces the effectiveness of the contact
between each fiber and the surrounding matrix and thus slightly reduces its conductivity. On
removing the load the concrete regains its original conductivity. Because of this peculiar property
the product is called “Smart Concrete”. The concrete could serve both as a structural material as
well as a sensor. The smart concrete could function as a traffic-sensing recorder when used as
road pavements. It has got higher potential and could be exploited to make concrete reflective to
radio waves and thus suitable for use in electromagnetic shielding. The smart concrete can be
used to lay smart highways to guide self steering cars which at present follow tracks of buried
magnets. The strain sensitive concrete might even be used to detect earthquakes.
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CHAPTER 5
Conclusion
The technologies using smart materials are useful for both new and existing constructions. Of the
many emerging technologies available the few described here need further research to evolve the
design guidelines of systems. Codes, standards and practices are of crucial importance for the
further development.
Sensors are playing a vital role in all sorts of sciences. Hence, instead of placing various sensors
at variable places in various application areas, it may be better to embed these sensors in
humanoids and it could be effectively used in detecting, monitoring, message conveying,
repairing etc., Thus the mobility of humanoids may be used effectively. A smart intelligent
structure includes distributed actuators, sensors and microprocessors that analyze the response
from the sensors and use distributed parameter control theory to command actuators, to apply
localized strains. A smart structure has the capacity to respond to a changing external environment
such as loads, temperatures and shape change, as well as to varying internal environment i.e.,
failure of a structure. This technology has numerous applications much as vibration and buckling
control, ape control, damage assessment and active noise control. Smart structure techniques are
being increasingly applied to civil engineering structures for health monitoring of buildings with
strain and corrosion sensors.A Smart material are just starting to emerge from the laboratory, but
soon you can expect to find in everything from laptop computers to concrete bridges.
Material
1.
High Performance
Uses
Advantages
Beam
On long span structures like bridges and
Conc.
2.
Light Transmitting
halls
Interior walls
Energy Saving
Paving, Parking, Walkways
Will be permeable for water
Conc
3.
Pervious Conc.
supporting water table recharge
4.
Floating Conc.
Marine architecture
Will save construction cost
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5.
Weave Metal Mesh
Half walls, Fences, Acoustic
Cost and time effective
walls
6.
Aerogel
Skylight, Thermal panels
Heat resistive, transparent
7.
Super Black
Paints, Varnishes and Finishes
Less Reflective, absorptive
8.
Banner work
Shading device, Landscape
Time, Cost, Energy efficient
element
9.
Geoweb
Vertical Gardening, Green
Energy conserving, Water
walls
conserving
10. Framing Track
Flexible boundaries and Fences
Quick and versatile
11. Rubber Side Walks
Foot path, Walkways
Waste managing, Time saving,
Eco-Friendly
12. Fly Ash Concrete
Beams, Columns, Slab
Repurposed , Provides strength
to base material
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References:
www.researchgate.net
www.enviro-edu.com
www.alibaba.com
www.chinawiremeshnetting.com
www.archiexpo.com
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