Polymer Composites in Construction: An Overview
Ayman S Mosallam1*, Alemdar Bayraktar2, Mohamed Elmikawi3, Salim Pul2 and Suleyman Adanur2
1Department of Civil & Environmental Engineering, University of California, USA
2Department of Civil Engineering, Karadeniz Technical University, Turkey
3Department of Structural Engineering, Ain Shams University, Egyp
Received: November 30, 2013; Accepted: January 28, 2014; Published: February 11, 2014
*Corresponding authors address:
Ayman S Mosallam, Department of Civil & Environmental Engineering, of California, Irvine (UCI), Irvine, California 92697-
2175, USA, Tel: +1-949-824-3369; Fax: +1-949-824-2117; E-mail: firstname.lastname@example.org
This paper provides an overview on some of the latest advances
in the applications of fiber reinforced polymeric (FRP) composites in
construction. The paper focuses on three main inter related review
areas, namely; (i) Repair and rehabilitation of concrete, steel, masonry
and wood structures using composites, and (ii) All-composite
structural applications that includes buildings and bridges, and (iii)
Latest development on design codes, materials specifications, design
manuals and national and international standards for composites
used in civil infrastructure applications.
This review examines recent developments related to fabricating ultrafine-grained titanium and biomedical titanium alloys by various kinds of SPD methods, such as equal channel angular pressing (ECAP), high pressure torsion (HPT), accumulative roll bonding (ARB) and friction stir processing (FSP). More specifically, the mechanical properties and performances of biomedical titanium alloys processed by ECAP, HPT, ARB and FSP have been investigated. It can be expected that in the near future, these techniques will be utilized as methods for continuous productions of the UFG biomaterials in large scale industrial applications.
Keywords: Construction; Highway bridges; FRP composites;
Rehabilitation; Repair; Safety; Impact; Fatigue; Reinforced concrete;
Beam-column joints; Wood repair; Steel repair; Masonry repair;
concrete columns; Bridge collision; LDPE composites; Codes;
In a recent report, the Federal Highway Administration
(FHWA) estimated that to eliminate the nation’s bridge deficient
backlog by 2028, we would need to invest $20.5 billion annually,
while only $12.8 billion is being spent currently. To make this
difference, federal, state, and local governments would need to
increase their bridge investments by about $8 billion annually
to address the identified $76 billion in need for deficient bridges
across the United States. It was also reported that traffic congestion
costs the US economy $67.5 billion annually in lost productivity
and wasted fuel. This costly traffic congestion is blamed, to a
major extent, on the existence of this increasing large numbers
of structurally-deficient and functionally-obsolete bridge.
Both weight and speed restrictions are required in the case of
structurally-deficient bridges. Functionally-obsolete bridges are
those designed according to older codes and load requirements
and are currently not capable of safely accommodate increasing
traffic volumes, vehicle sizes and weights. For this reason, there
is an urgent need for developing rapid and cost-effective methods
to repair structurally-deficient bridges and to upgrade the
functionally-obsolete bridges. In 2013 Report Card prepared by
the American Society of Civil Engineers (ASCE) stated that “..Over
two hundred million trips are taken daily across deficient bridges
in the nation’s 102 largest metropolitan regions. In total, one in nine of the nation’s bridges are rated as structurally deficient,
while the average age of the nation’s 607,380 bridges is currently
42 years…” .
Strengthening and repairing existing highway bridges as
well as other constructed facilities are considered to be major
challenges facing structural engineers worldwide. In the past
few years, a number of innovative methodologies for upgrading
the capacity of steel, concrete and timber bridges and structures
have been developed. However, the majority of these innovative
methods are still in the development stage and applications of
such technologies are still considered as demonstration projects.
This delay in moving innovative bridge developments from the
laboratory to field application is attributed to several factors
including liabilities-related concerns and conservatism on the
part of department of transportation (DOT) decision makers,
limitation of resources, lack of awareness of the technology and
its positive impact on bridge performance and most important
the absence of a standard concentrated approach for rolling out
innovations. In order to speed the technology transfer process
and to increase the confident level among engineers on the
performance of such new technologies, assessment tools such as
structural health monitoring and diagnostic/prognostic systems
are needed. These techniques will provide structural engineers
with updated information on the performance of repaired and
rehabilitated structural systems.
In this paper, selected successful applications of composites
are described. In addition a review of available standards,
acceptance criteria and design guides are also presented
Repair & rehabilitation of reinforced concrete
members using FRP composites
Repair and rehabilitation of reinforced concrete (RC)
columns was the first successful applications of FRP composites
that were initiated in early 1990 (Figure 1). This application
was extended other applications including RC beams, floor
slabs and bridge decks, beam-column joints, pipes, tanks, shear
walls and other structural members as shown in Figure 2. A
comprehensive coverage for different repair and rehabilitation
applications of composites is reported by Mosallam AS .
An effective multi-criteria systematic approach based on the
analytical hierarchy process (AHP) was developed to assist
decision-makers in evaluating the use of advanced materials by
El-Mikawi M & Mosallam AS . The AHP methodology provides
decision-makers with the means to evaluate the use of various
structural materials based on specific applications, optimizing
the use of limited resources. One of the key elements of the model
is the ability to handle complex problems and alternatives with
Emergency seismic repair of Reinforced Concrete
Bridge shear columns
During an earthquake of large magnitude, reinforced concrete
columns may be severely damaged limiting the functional
capacity of structures including highway bridges. It is essential
that damaged columns be temporarily repaired to ensure
continuous functionality and safety of essential structures. One
of the promising techniques is the use of FRP composite jackets
to regain its lateral capacity and to enhance its ductility. The
successful strengthening system must be pre-designed and be
readily available for fast implementation to mitigate further
damage that may be caused by aftershocks.
In a pilot study conducted at UCI to develop and evaluate
a rapid emergency repair technique for RC bridge columns.
In this study “as-built” column was subjected to full-reversal
cyclic shear loads were tested to failure. The unstrengthened
column was severely damaged as shown in Figure 3. A rapid
repair system comprised of a combination of fast-setting epoxy
mortar and four plies of unidirectional carbon/epoxy composites
jacket was developed and applied to the damage specimen.
The strengthened column was retested under identical lateral
cyclic loading (Figure 3). The repaired column showed excellent
performance as it developed flexural behavior with a ductility
of 4.0 as shown in the hysteresis loops in Figure 4. This clearly
demonstrates the effectiveness of such a scheme of repair that
can be used to provide fast emergency repair of bridge columns,
thereby reducing the traffic impacts due to bridge closure. Simple,
Figure 1: Repair and rehabilitation of corroded bridge & buildings RC
columns with FRP composites.
Figure 2: Examples of strengthening applications of FRP composites.
a. Floor beams; b. Floor slabs; c. Masonry walls; d. Pipes; e. Foundations;
f. Tanks; g. RC Shear walls
Figure 3: Full-scale cyclic tests of as-built and FRP-repaired RC columns.
yet effective semi-empirical models to predict the behavior of
RC columns with different geometries (e.g. rectangular, square,
circular, hexagonal, etc.) that are strengthened with both E-glass/
epoxy and carbon/epoxy jackets was developed by Youssef MN,
et al.  that was verified using the experimental results of
over 100 full-scale tests as well as available test results in open
Seismic repair and retrofit of reinforced concrete
Lack of joint confinement in the per-1970′s construction has
resulted in weakened link between the column and the beam and
collapse of the whole structure. The majority of past published
research work has focused on the repair and retrofit of the beamcolumn
exterior joints using either conventional materials or
off-the-shelf polymeric composites. For example, a pioneering
study introducing the use of composites for strengthening beamcolumn
joints was reported by Mosallam AS . Liu C  studied
the seismic behavior of beam-column joint assemblies reinforced
with steel fibers. Tsonos A  studied the effect of CFRP jackets
on retrofitting beam-column subassemblies. Supaviriyakit T &
Pimanmas A  conducted a study to compare the performance
Comparison between hysteresis loops of:
a. As-build column
b. FRP-repaired column
c. Comparison between load-displacement envelopes for repaired column
of a substandard beam-column joint with and without initial bond
between beam longitudinal bars and concrete in the joint core.
Pantelides C, et al.  conducted a research program for seismic
rehabilitation of RC frame interior beam-column joints with
externally applied CFRP composite laminates. Mosallam AS 
conducted a research study on structural upgrade of reinforced
concrete column-tie beam assembly using FRP composites.
An innovative externally strengthening technique for
reinforcing interior RC beam-column joints developed by the
author through the use of a hybrid High Performance Mortar
(HPM) and CFRP laminates. The hybrid HPM/CFRP composite
connectors are attached to both column and beams sides using
both high-strength bolts and high-strength epoxy adhesives
(Figure 5). In addition, multidirectional E-glass/epoxy and
carbon/epoxy composite laminates were designed for this
purpose. In order to verify the effectiveness of this strengthening
system, a comprehensive full-scale evaluation program was
conducted. Test results indicated that a significant enhancement
in the joint shear strength was achieved. The retrofitted beamcolumn
specimen strengthened with high-strength carbon/
epoxy composite laminates showed an improvement in its shear
strength capacity by 1.34 times as compared to the control
deficient specimen beam-column specimen. The experimental
results indicated also that the use of high-modulus carbon/epoxy composites in the focused deficiency application of this thesis was
not very satisfactory. For example, ductility of the high-modulus/
epoxy retrofitted specimen was 36% lower than as compared to
the high-strength carbon/epoxy retrofitted specimen. The use of
HPM/CFRP technique for retrofitting joint specimen with rebar
bond slippage was very successful. This innovative technique
improved the shear strength of the joint 2.5 times the control
deficient specimen. The use of advanced composite connector
has prevented brittle shear failure inside the joint region and
allowed a plastic hinge to develop away from the column face.
The energy dissipation by the retrofitted specimen was 4.6 times
the control specimen with discontinuous reinforcement rebars.
Figure 5: HPM/CFRP hybrid connector for strengthening of beam-column
Figure 6 shows the typical test setup for retrofitted beam-column
joints. The load-displacement for shear deficient control and
retrofitted specimens is presented in Figure 7.
Seismic repair and retrofit of reinforced concrete
shear walls with and without openings
Remodeling of existing structures can sometimes include
partial destruction of the structural members of a building as
shear walls (i.e. addition of window and door openings, ducts and
stairwells). In these scenarios, such buildings with new openings
must be retrofitted in order to restore the seismic capacity of
the structural member. Conventional retrofit techniques include
epoxy injection repair, concrete jacketing, steel jacketing, and
addition of external steel. Some of the attractive features of
FRP composites include high strength-to-weight ratios (specific
strength), higher corrosion resistance and ease of application.
The majority of published research focused on the retrofit of
solid shear walls [11-13]. However, there are very few studies
that involved evaluation of FRP retrofit of shear walls with
openings [14,15]. Recently, a comprehensive research program was initiated
at UCI to evaluate the effectiveness of the FRP retrofit system in
restoring the loss of capacity due to the addition of the openings.
The results indicated the innovative reinforcement systems
designed specifically to upgrade the performance of the walls
after the introduction of the openings that were not included
in the original wall design performed in a satisfactory manner
and were able to restore the capacities of the retrofitted walls to
more than or equal to the average capacity of the original solid
wall without openings. Geometrical and reinforcement details
for the wall specimens evaluated in this study are described in
Figure 8. The failure modes of as-built and retrofitted wall with
opening specimens are shown in Figure 9. A comparison of loaddisplacement
envelopes of all wall specimens is shown in Figure
10. As shown in this figure, ductility of the retrofitted wall with
door opening was 3.33 as compared to 5 for the control (as-built)
wall with door opening due to the localized severe debonding
failure of the retrofitted wall at the connection between the
Figure 6: Typical test setup for retrofitted beam-column joints.
Figure 7: Load-displacement for shear deficient control and retrofitted
top spandrel and the narrow wall pier. In addition, the average
ultimate load of the retrofitted wall with window opening was
1.32 times the average ultimate load of the control wall with
window opening. For the retrofitted wall with door opening, the
average peak load was 1.25 times the average peak load of the
control wall with door opening.
Flexural upgrade of reinforced concrete slabs with a
Few decades ago, steel plates have been used to enhance
flexural strength of RC floor slabs and bridge decks by externally
bonded fiber reinforced polymer (FRP) composite systems have
been accepted by the construction industry. Several research
studies have confirmed the effectiveness of this retrofit protocol
for both reinforced and unreinforced concrete slabs subjected
to both static and blast loads [16,17]. Although composites can
resist compressive stresses, for rehabilitation applications, it
is not recommended , 2008). For this reason, externally
bonded FRP system is preferably used to strengthen concrete
members subjected to tensile stresses. Conventionally, composite
laminates are installed at the top and the underside of floor slabs
or bridge decks to enhance both negative and positive moment
capacities (Figure 11).
While the FRP installation at the top of floor slabs or bridge
decks has not met many difficulties, in most cases there are many
obstacles to access the underside of the slab such as suppression
system, electrical wiring and ventilation ducts. This also applies
to retrofitting bridge over passes where traffic interruption in
the road below is unavoidable as well bridges over waterways
where the application of retrofit systems requires special
shoring and special application procedures that are expensive
and cumbersome in most cases. Therefore, it might be difficult
to achieve the well prepared concrete surface for the FRP
application at the underside of the slab or might not have access
at all for logistic reasons. Moreover, additional anchoring or equipment might be necessary to hold FRP laminates during the
Figure 8: Wall specimens details.
a. Solid wall specimen
b. Wall specimens with a window opening
c. Wall specimens with a door opening
Figure 9: Failure modes of as-built and retrofitted wall with opening specimens.
initial curing of an adhesive, which makes it further difficult to
apply the FRP to the underside of slab or bridge deck.
Recently, a pilot project was initiated to develop an
innovative hybrid composite system is proposed combining a
high performance mortar (HPM) with carbon fiber reinforced
polymer (CFRP) in the presence of adequate shear connectors.
By integrating these two materials, the ability of the proposed system to increase the moment carrying capacity of RCs labs
or bridge decks is demonstrated [19,20]. The proposed system
can be installed on the top of the RC slabs or deck to enhance
the positive moment capacity (Figures11 & 12). A one-way slab
with two continuous spans of 1219 mm wide and 2438 mm long
is considered to examine the proposed system ability to enhance
the moment capacity of the slab. Three identical one-way slabs
were constructed and the proposed retrofit system is installed to
Figure 10: Comparison of load-displacement envelopes of all wall specimens.
HPM/CFRP retrofitting mechanism for a section subjected to positive and negative bending moments.
a. Load distribution for a one-way RC slab and corresponding bending moment and shear force diagrams
b. Retrofitting mechanism for a section subjected to negative bending moment (section A-A)
c. Retrofitting mechanism for a section subjected to positive bending moment (section B-B)
two of the slabs. Two types of HPC with compressive strength of
69 and 97 MPa were examined. Full-scale experimental results
indicated that the proposed system can increase the ultimate load
capacity and ductility of the retrofitted RC slabs by about164%
and 122%, respectively, as compared with the original ‘‘as-built’’
capacities with easy installation. Based on the verification test
results, the system was approved by the City of Los Angeles,
California and was adopted for use for a commercial high-rise
moment frame building in Los Angeles, California (Figure 12).
Collision protection system for reinforced concrete
One of common damages in existing highway bridges is the
localized damage at the bottom corners or edges of the reinforced
concrete beams or box girders induced by an impact of trucks exceeding the allowable height clearance of the bridges. Due
to collision impact of the trucks, the bottom or outer layers
of concrete girders are usually peeled off (Figure 13-a) so
that the steel reinforcements are exposed to the surrounding
environment and subjected to corrosion. This issue is also related
to protection of reinforced concrete bridge superstructures and
piers subjected to potential impact by barges and ships (Figure
13-b). A collision protection or scarifying system is in pressing
need, and it can protect the concrete girders and piers from
such impact damage and thus ensure the integrity of the bridge
Functionally-degraded sandwich system for over-height
collision protection of highway bridges: Mosallam AS (2004)
developed an innovative functionally-degraded sandwich
Figure 12: Field application of the HPM/CFRP system for flexural upgrade of floor slabs.
Impact damages in the concrete bridge girders by over-height trucks and buses.
a. Collision damages of highway bridges by buses and trucks
b. Collision damages of highway bridges by ships
system (I-Lam1*) to act as a scarifying impact system for
reinforced concrete members. The system was presented to the
Federal Highway Administration through Ohio Department of
Transportation as part of the IBRC-T21 program. The four major
objectives of this pilot research are: (i) to develop general design
for the functionally-degraded collision protection system based
on the specified site conditions and construction requirements,
(ii) to conduct numerical simulation, optimal design, and quality
control tests of the collision protection system  (iii) to
implement the developed collision protection system in identified
damaged bridges or new constructed bridges, and to re-deploy
the system if damage occurs, and (iv) to monitor the short- and
long-term performance of the collision protection system using
smart sensors and actuators and remote sensing technology.
In the full-scale impact evaluation phase, the concrete beam
was instrumented with two (2) load cells to measure longitudinal
force. The sled was instrumented with two (2) longitudinal
accelerometers, which were pre-filtered with an analog filter
to 200 Hz as an integral part of the sled firing circuit, and two
(2) additional accelerometers: the primary accelerometer for
pulse and integrated velocity determination and a backup
accelerometer. In addition, the sled was instrumented with one
(1) light trap to measure velocity. The tests were filmed by two
(2) high-speed digital cameras set to view the test article, and
operating at 1,000 frames per second. The four-test series was
conducted at the Transportation Research Center (TRC) facility
in Ohio using a custom designed test fixture shown in Figure 14.
The fixture included a mounted concrete beam, I-Lam interface
specimen, and a wooden impactor. Each test was designed to
produce an impact speed of 20.0 m/s (~45mile/hour) between the wooden impactor and the I-LAM interface sample. A single
test was performed under the same conditions with the wooden
impactor striking the concrete beam.
Results of the full-scale tests confirmed the success of the
I-Lam system in protecting the RC beam from both localized and
global damages. The as-built unprotected beam experienced
severe damages with major concrete spalling and distortion of
the steel reinforcement. As shown in Figure 15, minimum damage
occurred to all I-Lam protected beams specimens. Only surface
evenly distributed flexural hair cracks were observed, especially
at the back side of the beam (tension side).
Based on the success of the I-Lam system, Ohio Department
of Transportation (ODOT) has approved the installation of the
system on one of problematic bridges in Ohio. Figure 16 shows
the installation procedures for the I-Lam system.
Hybrid LDPE/FRP collision protection system for bridge
RC piers: Several marine applications using recycled hybrid
systems were constructed as demonstration projects by the
US Army Corps, US. Navy, port authorities in USA (e.g. Port
Wanimaie, Delaware Port Authority, etc.) and recently, California
Department of Transportation (Caltrans). Caltrans introduced a
new structural application for highway bridges where recycled
LDPE/FRP hybrid beams (or camels) are used as a protection
system for highway bridge abutments from potential impact by
ships and barges. A pilot study aimed at evaluating both the service
and the ultimate behavior of recycled Low-density Polyurethane
(LDPE) beams reinforced with glass fiber reinforced polymer
(GFRP) composites rebars . The objective of this study was
to conduct pre-qualification full-scale tests for this hybrid system
forship collision protection system for Oakland Bridge and other
Typical test setup for full-scale impact tests.
Comparisons of unprotected and I-Lam protected reinforced
concrete beams before and after impact.
a. As-built unprotected beam before impact
b. As-built unprotected beam after impact (severe damage is
c. I-Lam protected beam before impact
d. I-Lam protected beam after impact (only minor cracks are
First field application of the I-Lam over height collision protection
System in Ohio, USA.
California bridge piers (Figure 17). The study comprised of largescale
experimental evaluation as well as the development of a
simple closed-form analytical model capable of predicting the
flexural behavior of the hybrid beam. In the experimental program,
two different composite reinforcement details were evaluated
and full-scale specimens were subjected to four-point quasistatic
loading/unloading and loading-to- failure protocols (Table
1). In addition, axial tensile and compression coupon tests were
conducted to characterize the short-term mechanical properties
of LDPE matrix. All large-scale specimens were inspected for
any manufacturing defects and voids prior to testing, and
measurements of each specimen were recorded. Displacement,
strains and loads were continuously monitored and collected
during all tests using a computerized data acquisition system. In
all full-scale tests, the behavior of the hybrid beams was linear
up to about 80% of the ultimate load, after which the behavior
became nonlinear up to ultimate load. No failure or cracks were
observed in the LDPE plastic matrix, and the governing mode
of local damage was in the form of relative slippage of the FRP
rebars at the ends, especially the top compressive reinforcements which, accordingly, resulted in appreciable stiffness loss (Figure
18). Due to the very large deformation of the hybrid beams, the
maximum applied load for the tests was limited by the actuator
stroke capacity. An analytical model was developed to predict the
flexural behavior of the hybrid system. The analytical model is
based on deformation compatibility and force equilibrium using
section analysis procedure.
Structural upgrade of steel members using FRP
Despite its great potential, limited information is available
on bonded fiber-reinforced-polymer composite to steel. A pilot
project aims at investigating the feasibility of using a combination
of polymer composites, high-strength adhesives as strengthening
system for upgrading the structural performance of bridge
steel members has been conducted. In addition to the benefit
of upgrading the structural capacity of steel members, results
of a prior Federal Highway Administration (FHWA) sponsored
research study indicated that attaching a cover plate to the
tension flange of a steel girder with longitudinal welds along
the central region, and with friction-type high-strength bolted
connections at the non-welded ends, could increase the fatigue
life by a factor of 21 over that of conventionally end-welded
cover plate. Accordingly, end-bolted cover plates have Category B
fatigue strength, whereas end-welded cover plates have Category
The use of adhesives provides attractive features for
strengthening existing under-rated bridge steel members. This
includes the ease of applications, minimizing heavy equipment,
minimizing or eliminating the need for making holes or using
bolts. As a result, this approach can provide the structural
engineers with quick and low cost fix for different members
such as bridge steel girders and columns. The motivation of this
research study was initiated by the urgent need to increase the
static flexural capacity of the steel girders of the Sauvie Island
A pioneering research project on the use of composites and
high-strength adhesives in seismic repair and rehabilitation of
Examples of field application of LDPE-GFRP for bridge collision
LDPE/FRP hybrid beams test matrix. *Cover = 1ʺ [25.4 mm], **Cover = 3/4ʺ [19 mm]
Typical LDPE/GFRP beams test setup and failure mode.
welded steel moment frame connections was initiated by the
author [22,23]. Full-scale test results indicated that the used of
bonded carbon/epoxy stiffeners resulted in an increase of more
than 25% of the undamaged welded steel connection strength. In
addition, the ductility of the repaired connections was enhanced
with a plastic rotation capacity of more than 0.025 rad., which was
required by Federal Emergency Management Agency (FEMA).
One of the first investigations on the use of carbon/epoxy strips
in strengthened steel girders was reported by Sen R & Liby L .
A case study on the use of composites in upgrading the structural
capacity of steel girders was reported by Garden HN & Shahidi EG
. In this case study, the steel girders were heavily corroded
and were repaired, after cleaning and geometrical restoration, by composites that were applied using a vacuum bagging method.
Whether this repair was appropriate given the advanced
corrosion stage of the repaired, is still questionable.
Tavakkolizadeh AM & Saadatmanesh H  presented the
results of a study on repairing steel girders using precured carbon/
epoxy strips. In this study, a total of three large-scale composite
(steel/concrete) girders were repaired using different composite
strengthening ratios with different degrees of simulated damages
were evaluated. A similar study was conducted by Photiou N 
on artificially degraded steel box beams using prepreg carbon/
glass U-shaped laminates. Test results showed a significant
increase in the strength and stiffness of the repaired beams. The
use of high-modulus carbon/epoxy laminates for strengthening
steel members and towers was studied by Schnerch D, et al. 
& Peiris NA . Zhao XL & Zhang L  presented a state-of-theart
review on FRP strengthened steel structures. It was concluded
that further research is needed specifically on understanding the
bond–slip relationship; the stability of CFRP strengthened steel
members, and fatigue crack propagation modeling.
The H-Lam System2*
The innovative sandwich system was developed by the
author specifically for steel strengthening applications. The
reinforcing honeycomb polymer composite panels consist of
high strength composite facing sheets bonded to a lightweight
high density/high strength core material. The H-Lam panels were designed such that they are both thermally and mechanically
balanced. The face sheets of the composite sandwich panels
are comprised of 0o/90o carbon/epoxy laminates with E-glass/
epoxy thin laminates at the interface with the steel girder and
the aluminum honeycomb core. The reason for using 90o cross
laminates is for stability of the unidirectional laminates during
both the fabrication and during service.
The H-Lam system used in this application has an E-glass/
epoxy cover layers to protect the carbon-based composite panel
from galvanic corrosion (the galvanic corrosion occurs upon
direct contact of the carbon/epoxy to steel in the presence of
moisture, which in this application is unavoidable). In addition,
the H-Lam panels have an E-glass peel-ply (Figure 19) to protect
the pretreated face sheet to be bonded to the steel bottom
girder. This functions of the added peel-plies are: i) to ensure
a high quality shop surface preparation of the composite face,
ii) to protect the composite panels from damages and surface
contamination while handling and shipping and iii) to minimize
the field surface treatment.
Unlike the general-purpose epoxy used for the off-the-shelf
CFRP (Carbon/epoxy Fiber Reinforced Polymer) composite
strips system, which was originally developed for concrete and
masonry, the H-Lam adhesive system was engineered specifically
for steel strengthening application. In addition, the H-Lam system
offers the choice of using either bond-only or bond/bolted joint
between the composites and the steel member. However, in
this application, the bond-only system was used to avoid any
alteration to the existing steel girders.
In designing the adhesive system, several criteria
were considered including: i) the surface preparation and
treatment requirements (ease of field application), ii) viscosity
(workability), iii) temperature variation, and long-term durability
requirements including wet environment, iv) toughness and
strain compatibility with steel and composites, v) fatigue
resistance and vi) strength and stiffness requirements. Instead of
the general-purpose epoxy adhesives used for bonding the CFRP
strips, a methacrylate adhesive system was designed and used
for bonding the H-Lam panels.
The cyclic results indicated the stability of the bond line
of the H-Lam strengthened beam at both zero and maximum
shear stresses locations, while the CFRP strips may have shown
instability, at end locations where shear stresses are maximum.
The results of the ultimate tests indicated that the use of the
composite system increases the flexural capacity of the control
beams. The net strength gain for specimens strengthened with
the H-Lam system was almost double of the strength of the beam
strengthened with the CFRP strips (27.5% vs. 15.4% as compared
to the ultimate capacity of the control steel beam). Although, test
results indicated that the H-Lam strengthened beam system
resulted in an increase in toughness up to 45% as compared to
the control specimen while the CFRP strips strengthened had
42% lower toughness as compared to the control specimen
(Figure 20). No laminate or bondline failure occurred under both
cyclic and quasi-static ultimate loadings and the failure was in
the form of local buckling of the top flange as shown in Figure 21.
Flexural upgrade of sauvie island bridge steel girders
using H-Lam technology, Portland, Oregon, USA
Based on the successful verification tests results, the H-Lam
system was approved by the Bridge Department for actual bridge
installation. The field application was performed on selected
The H-Lam peel-ply.
Toughness comparison between the three half-scale specimens.
Ultimate failure of the h-lam strengthened beam specimen.
steel girders of a selected span of the Sauvie Island Bridge
(Figure 22). All composite panels, adhesives and tools were
transported to the site at the same day of application. The field
application took place on a Sunday to ensure minimum traffic
interruption. In addition, a traffic restriction (from 12 p.m. to
9 p.m.) for all vehicles over 10 tons was posted on the bridge
two weeks prior to the construction date. Temporary clamping
steel/plywood fixtures were used for applying pressure to the
composite panels during curing and were removed after one day
of application. The application was completed in 5 hours and the
panels were instrumented with strain gages in different locations
for the third ongoing health-monitoring phase. In addition to
strain monitoring, several composite samples were adhered to
steel using the same types of adhesives that were subjected to
the same field environment. Frequent pull-off tests are being
performed to monitor the long-term bondline strength at
different environmental exposures. Detailed information on this
project is reported by Mosallam AS .
Repair & rehabilitation of wood members using
As compared to other structural applications of polymeric
composites, limited information is available on structural behavior
of wood members strengthened with polymer composites. One of
the first applications was initiated in mid-1990, where E-glass/
epoxy laminates were used to restore damaged wooden utility
poles and this application was further studied by Polyzois D &
Kell JA . Similar application of strengthening wood piles
with composites was also investigated by Lopez-Anido R, et al
. One of the pilot applications for developing a hybrid gluedlaminated
wood by introducing thin laminates of E-glass/epoxy
composites between the wood layers was introduced by Tingley
D . During the past two decades or so, several papers were
published discussing critical issues related to this application. For
example, Gilfillan JR, et al.  studied the structural behavior of
several Irish-grown Sitka timber beams strengthened with both
composites and steel. These beams were evaluated under both
short- and long-term mechanical loading. Experimental results
indicated that an appreciable strength gain was been achieved
for beams strengthened with FRP composites. Triantafillou TC
 studied the application of unidirectional and cross-ply FRP
composites in enhancing the shear strength of glulam wood
members. The experimental program included a total of twentyone
small-scale beam specimens that were subjected to 4-point
loading regime. A simple analytical procedure was proposed and
results were compared with experimental values.
A new generation of advanced composites for structural
upgrade of wood members was developed by Mosallam AS (2013)
similar to the H-Lam system discussed earlier for strengthening
steel members. However, the fiber architecture of face sheets
and core material type was different for wood applications. This
repair system utilizes the concept of thin sandwich panels that
is bonded and also screwed to the wood member (Figure 22).
The advantages of using sandwich panels in this application
includes: (i) ease of application, (ii) increase in quality control
of the prefabricated materials and shop pretreated surfaces, (iii) light-weight features, (iv) the presence of stiffened holes allows
for drilling metal screws or nails that will act as both shear
connectors and prior to adhesive curing as a temporary clamps,
(v) superior fire properties due to higher glass-transitiontemperature
(Tg) and the use of phenolic matrix, and (vi) overall
all economic advantages. The face sheets of the sandwich panels
are fabricated from a low-smoke carbon/phenolic laminates
bonded to an aramid honeycomb core using high-temperature,
high-press manufacturing process. The fiber architecture of the
two face sheets were in the form of cross-ply [0o/90o/c]s (c=half
of the core thickness) thin laminates with a unit thickness of 0.75
mm (0.03”). Equal fiber volume fractions for both longitudinal
and transversal directions was used, with an overall fiber volume
fraction for both directions equal to 70% for face sheet laminates,
assuming a zero void ratio.
In developing this Honeycomb Laminated system (referred to
as H-Lam hereafter), several design parameters were considered
including: (i) resin compatibility with wood, (ii) pre-treatment of
the composite surface to be bonded to wood, (iii) providing selfclamping
mechanisms to hold the H-Lam in place during the antigravity
application at the site, (iv) fire resistance, (v) economic
considerations and (vi) strength and stiffness requirements.
These design targets were achieved by optimum design of face
sheets and core; pretreatment of the face sheets, selection of
fire retardant matrix and core materials, introduction of central
through-the-thickness stiffeners and holes at equal spacing of
25.4 mm (1”) along the span of the panel. With this arrangement,
the applicator is able to use nails or screws to hold the H-Lam
in position after applying the low-viscosity primer and the highviscosity
adhesives in addition its partial role as mechanical
shear connectors (Figure 23). The width of the H-Lam is 152 mm
(6”) and the total thickness of the H-Lam is 10 mm (0.4”) with an
average face laminate thickness of 0.74 mm (0.029”).
Two types of composites; wet layup and sandwich panels,
and two lamination schedule; unidirectional and bidirectional,
and two lamination geometry, U-laminate and flat laminates
were evaluated. For “flexure-shear” wood beams repaired and
retrofitted with bidirectional, carbon/epoxy U-shaped wet layup
Field application of the h-lam system for the sauvie island
bridge, Portland, Oregon, USA.
FSandwich composite panels for strengthening wood members.
laminates, a total of eight 203 mm X 203 mm X 3.0 m (8” X 8”
X 10’) Douglas Fir (Dug Fir) Larch # 1 wood beams were tested
to failure. Experimental results indicated that, in general, the
use of composites as external repair and rehabilitation elements
resulted in an appreciable increase of both strength and stiffness
of the as-built wood beams. For example, test results indicated
that an increase, up to 180% of the strength of pre-damaged
beam repaired with carbon/epoxy composites is achieved. In
addition, the flexural stiffness of the strengthened beam was
upgraded to about 150% as compared to the pre-damaged beam
specimen. Figure 24 presents load-displacement curves as-built
wood beam and strengthened beams with flat unidirectional
CFRP laminate and H-Lam system. As shown in this figure, the
H-Lam strengthening system has superior stiffness, strength
and toughness as compared to both the as-built and flat CFRP
strengthened wood beams.
Repair & rehabilitation of masonry walls using
One of the successful applications of FRP is upgrading the
seismic performance of unreinforced masonry (URM) walls,
which are the primary load carrying components of unreinforced
masonry buildings. In old building constructions, these walls
were primarily designed to carry gravity loads. Due to the absence
of any lateral load carrying component, such constructions are
generally fragile during ground excitation resulted from seismic
events. In fact, a significant damage of these walls is observed
in past due to earthquakes . Hence, seismic retrofitting of
these buildings is required in order to upgrade their seismic
performance and improve the ductile behavior. Experimental
research demonstrated that the external application of FRP
composite laminates either on single or on both sides of masonry
walls can remarkably enhance their in-plane and out-of-plane
shear carrying capacity [38,39]. A comprehensive literature
review on this can be found in ACI 440.7R-10 . In conjunction,
numerical studies have also been performed by developing
finite element models to predict the in-plane behavior of FRP
retrofitted masonry walls . It is observed that the degree
of enhancement of wall capacity greatly depends on several
factors such as the wall aspect ratio, masonry type (brick, stone
or concrete), retrofitting scheme, type of FRP material used, and
application of later alloads (in-plane or out-of-plane). In addition,
the purpose of FRP application either to repair partially damaged
walls or to retrofit undamaged walls can make considerable
difference in wall shear strength enhancement.
Haroun MA, et al.  conducted a comprehensive verification
experimental program on cyclic in-plane shear of concrete
masonry walls strengthened by FRP laminates. In this study,
different types of composites including E-glass and CFRP wet
layup laminates as well as pre-cured CFRP strips were evaluated
(Figure 25 & Table 2). The reported experimental results
demonstrated the effectiveness of different FRP materials and
lamination schemes in order to externally repair or retrofit URM
walls. A significant gain in in-plane shear capacity is observed
when the walls are strengthened with FRP composites on either
one or both sides of walls. The key experimental observations are:
(i) the application of FRP in order to repair the pre-cracked wall
resulted in 20% gain in the in-plane shear capacity in comparison
with the as-built wall; (ii) a maximum increase of 35% is achieved
in the in-plane shear capacity of URM walls when the walls are
retrofitted with FRP; (iii) due to retrofitting, the ultimate failure
mode changes from diagonal cracking of walls (brittle failure in
nature) to compression failure at one of the wall toes (ductile
failure in nature); (iv) the yield and ultimate displacements of
the retrofitted walls are recorded as considerably higher than
the same of the retrofitted wall. Figure 26 presents the load-
Load-deflection curves for unstrengthened and FRP
strengthened wood beams.
Samples of masonry walls retrofitted with FRP composites:
a. Carbon/epoxy procured strips
b. Carbon/epoxy wet layup laminates
displacement envelops for all wall specimens. Table 1 & Figure
27 show a summary of the ultimate shear strengths of different
Mosallam AS & Banerjee S  calculated the strength
capacities of the walls investigated by Haroun MA et al.  using
currently available code-based and research-based analytical
models. Four analytical models were used according to their
applicability for different retrofitting schemes. A comparison of
analytical result with experimental observations indicated that
analytical models are very case specific and their applications
are very restrictive. Thus further studies are needed to develop
analytical models that will be generally applicable to a higher
population of concrete masonry walls externally retrofitted with
different combinations of composite materials and lamination
Summary of ultimate strength values for all masonry wall
Load–displacement envelopes for as-built and retrofitted
Strength comparison between all masonry wall specimens.
All-composites structural applications
In addition to the repair and reinforcement application of
composites in construction, composite materials are being used
to build the entire structure such as warehouses, buildings,
highway and pedestrian bridges and bridge decks as well as
other civil engineering structures. One of the popular types of
composites in construction applications is pultruded composites.
For decades, pultruded fiber reinforced polymeric (PFRP)
composites have been used as secondary structural members
in several construction applications such as petrochemical
plants plate forms, cooling towers structures, and in water
and wastewater treatment plants applications. The pultrusion
process is a continuous manufacturing process where the
saturated fibers are pulled through heated die using continuous
pulling equipment. The hardening or gelation of the resin
is initiated by the heat from the die producing a cured rigid
pultruded profiles that are cut to length by an automated saw.
Pultrusion is considered to be the only closed mold process that
allow for combining a variety of reinforcement types and hybrid
in the same section. Most of the commercially produced PFRP
structural shapes are composed of multilayers of surfacing veil
or Nexus™, continuous fibers (roving), and continuous strand
mat. The typical volume fraction of fibers for “off-the-shelf”
sections is in the range of 40% to 45%. A variety of structural
profiles (open and closed-web) are now available similar to steel
sections (H, I, C, L,...). The major reinforcements of these sections
are concentrated in the longitudinal direction of the section with
minimum reinforcement in the transverse direction. The most
common fiber type is the E-glass in the form of rovings and strand
mats. However, recently carbon/E-glass composite profiles have
been produced in limited bridge applications.
As shown in Figure 28, with few exceptions, the majorities
of the off-the-shelf pultruded profiles are similar, in geometry, to steel profiles and are commercially available in different sizes
and grades. Although the use of unidirectional reinforcement
schedule may be satisfactory for lightweight or secondary
structural members, it is indeed not sufficient for primary
structural carrying members such as bridge decks, girders and
columns. Other disadvantages of using thin-walled unidirectional
“steel-like” PFRP profiles are the insufficient lateral and
buckling resistance of the section. In addition, in the majority of
commercially produced unidirectional open-web (e.g. H-profile,
Channels, angles, etc.) and closed web (e.g. rectangular and box
profiles) there is a lack of fiber continuity between the web(s)
and flanges [44-46]. For this reason a premature failure at the
web/flange junction is the common mode of failure of such
profiles (Figure 29). A comprehensive discussion on this issue is
reported by Mosallam AS .
Several projects have been constructed entirely using
pultruded fiber reinforced polymer (PFRP) composite sections as
the main structural elements. One of the early applications is the
construction of four PFRP turret towers on top of the Sun Bank
Building, Orlando, Florida. Figure 30 shows one of the three-story
high towers framing, which was built entirely from pultruded
fiber reinforced plastics (PFRP) shapes (H, angles, threaded rods
and nuts). All columns and girders were constructed using openweb
H sections, which were connected together using FRP bolts
and nuts. The use of PFRP composites was the preferred choice
because of the electromagnetic transparency and radio wave
reflection properties of composites. Due to the non-magnetic
properties of PFRP composites, it is commonly used for facilities
with delicate instrumentation.
The first residential/office building with PFRP structural
profiles was presented as the Eyecatcher Project at the
Swissbau’99 Fair in Basel (Figure 31). After the exhibition, the
construction was disassembled and brought to its new location
at Münchensteinerstrasse 210, Basel where it now serves as
a permanent office building. The Eyecatcher all-composite
building is open to the public on agreement. The height of the
all-composite 5-story building is 15 meters (49.21 feet) (with a
ground floor area of 10 meters X 12 meters (30.48 feet X 39.37
Off-the-shelf pultruded composites.
Resin-Rich zones at web/flange junction of unidirectional
35’ (10.7 m) High x 35’ (10.7 m) square base pultruded turrets
on top of the sun bank building tower, Orlando, Florida, USA.
The eye catcher pultruded building during and after construction.
feet). The inclined and vertical columns were fabricated as a
build-up section made of one H-profile and two U-profiles. The
horizontal frame girders were also built-up sections made of
two U-profiles and four flat pultruded plates. In all built-up
sections, the pultruded composite profiles were bonded using
high strength epoxy and were subsequently bolted together with
In the USA, there are over 90,000 weight-restricted bridges
U.S. In most cases, there is no enough budget allocated solve the
problem by replacing these decks. These bridges are frequently
replaced with a modern multi-girder design to restore the route
to traffic without weight restrictions. To replace the bridge would
have cost $2.4 million. In the past few years, FRP composite
decks have proven to be an ideal solution of this problem was
a cost reduction up to 30% in additional the tremendous saving in construction time and traffic interruption. In the past two
decades or so, several US Departments to Transportation (DOT)
have utilized composite decks to replace corroded and under
rated bridge decks. The US Federal Highway Administration
(FHWA) has initiated a major research and development program
focusing on innovative technology for extending the service life
of US bridges. The program is called Highways for LIFE. A report
describing new FRP deck design and application was published
in 2013 . Table 3 presents data on some of the different FRP
composite decks projects in different states. In the following
paragraphs, few examples of utilization of FRP bridge decks are
The Schuler Heim composite decks, long beach,
California, USA: Unlike the majority of previously reported FRP
bridge deck applications on the use of composite bridge decks to
replace corroded reinforced concrete existing bridge decks ,
the fatigue problem associated with welded steel gratings was
the primary motive behind the selection of composites. The lift
span of the 55-year old, 1,212-ft (370 m) long four-lane Schuyler
Heim steel bridge located in Long Beach, California (Figure 32),
have been suffering from localized failure of welded steel gratings
due to the high fatigue and impact loads resulting from the heavy truck traffic in and out the Terminal Island of the Long Beach
Harbor. It is equipped with a 224-ft (68.3 m) lightweight opengated
steel deck, which lifts to allow ships to pass. The lift has a
5-inch (127-mm) deep deck supported by steel girders spanning
the width of the deck every 4 ft (1.22 m). A dramatic increase
in traffic has forced Caltrans to replace the steel deck twice over
the last 10 years. The California Department of Transportation
(Caltrans), being the leading governmental organization in the
U.S. since early 1990’s in promoting the use of composite and high
performance materials and systems in both seismic repair and
bridge applications, decided to take the advantages of the known
high fatigue characteristics of polymer composites to establish an
effective remedy to this problem. The primary design criteria for
Caltrans were limited by weight and profile depth. The weight
of the composite deck was limited to 24 lbs/ft2 (1.15 kPa) with
a maximum total depth of 5 inches (127 mm) in order to match
the existing grades of the bridge. In addition, Caltrans specified
that the new composite deck should be designed to carry 1.25
of the current rated capacity of the welded steel bridge deck (90
kips/400 kN vs. 72 kips/320 kN). According to the American
Association of State Highway and Transportation Officials
(AASHTO) criterion, the deflection of the new composite deck
Table 3: Samples of FRP composites bridge decks installed in USA
BRIDGE PROJECT LOCATION
MANUFACTURER & EVALUATOR
Redstone Arsenal, Alabama
Kings Stormwater Channel Bridge, SR86 Riverside Co.
MMC-Glassforms & UCSD
Schuler Heim Lift Span, Long Beach, CA
MMC & UCI
Bridge 1-192 Old Milltown Road over Mill Creek, New Castle, DE
Magazine Ditch bridge, New Castle Co.
Bridge 1-351 SR896, Glasgow, DE
Belle Glade, Florida
INEEL bridge, Idaho Falls, ID
South Fayette St/Townbrook, Jacksonville, IL
Lafayette, Tippecanoe County, Indiana
3rd Ave/Crow Creek, Bettendorf, IA
No Name Creek bridge, Russell, KS
Pittsburg, KS, two KSCI bridge decks
MD 24/Deer Creek Harford Co., MD
North Bank Bridge (bicyclist bridge)
City of St. James, MO
KSCI deck on steel
City of St. James, MO
KSCI deck on steel
City of St. James, MO
KSCI deck on steel
NY 248 / Bennetts Creek, Steuben Co., NY
St. Lawrence County, NY
NY 367 / Bentley Creek, Chemung Co., NY
NY 223 / Cayuta Creek, Chemung Co., NY
NY 418 / Schroon River, Warrensburg, Warren Co., NY
CR 46 (Osceola Rd) / E Br. Salmon River Lewis Co., NY
CR 52 (Triphammer Road) / Conesus Lake Outlet, Livingston Co., NY
KSCI - HC
SR 1627/Mill Creek Union Co.
Salem Ave (SR49) / Great Miami River, Dayton OH
4 deck suppliers
Smith Road (Tech-21) bridge Butler Co.
SR 47/Woodington Run Darke Co., OH
MMC on steel
Westbrook Road, Montgomery Co.
B-0171 Five Mile Road, Hamilton Co.
Three bridges (HC)
Stelzer Road, Columbus, OH
Tyler Road bridge, Delaware Co., OH
Hebble Creek, Dayton OH
Hamilton County, Ohio
Summit County, Ohio
Lewis & Clark Bridge, Astoria, Clatsop Co., OR
Old Youngs Bay Bridge, Clatsop Co., OR
Broadway Bridge, Multnomah County, Portland, OR
MMC - ZellComp
Morrison Bridge, Multnomah County, Portland, OR
SR 4012/Slippery Rock Creek Boyers, PA
T-565 over Dunnings Creek, Bedford County, (MMC)
S-655(Greenwood Road)/Norfolk Southern Railroad Spartanburg Co., SC
Troutville Weigh Station, VA
Tom's Creek Bridge, Blacksburg, VA
Dicky Cr, Sugar Grove, VA
Wolf Creek National Park near Vienna, VA (pedestrian bridge)
Tangier Island, VA
Market St. Bridge, Wheeling, Ohio Co., WV
Laurel Lick Bridge, Lewis Co., WV
Wickwire Run Bridge, Taylor Co., WV
Hanover Bridge, Pendelton Co., WV
Boy Scout Camp Bridge, Raleigh Co., WV
Katy Truss Bridge, Marion Co., WV
La Chein Bridge, Monroe Co., WV
FRP deck on steel
Montrose Bridge, Randolph Co., WV
West Buckeye Bridge, Monangalia Co., WV
Howell's Mill Bridge, Cabel Co., WV
CR 1 over Mud River (Howell's Mill Bridge), Cabell County, WV
Kite Creek Bridge, Monroe Co., WV
FRP deck on steel
Goatfarm Bridge, Jackson Co., WV
FRP deck on steel
US-151 / Hwy 26
CDS hybrid deck system
29th Street Bridge, DC
should not exceed its span length divided by 500 (L/500) or in
this case 0.096” (2.5 mm) .
Full-scale experimental results indicated that the composite
bridge deck has exceeded both the predicted design and ultimate
capacities. The span-to-deflection ratio at the mid-span was
L/738 based on a span length of 48” (1.22 m). The average safety
factor (SF) of the composite deck prototype was 6. In all tests, the
ultimate failure was initiated either by a punching shear under the loading steel plate, or/and by the delamination of the curved
portion of the drop sandwich panel. In modeling the performance
of the composite deck, the GENOA progressive failure analysis
numerical code was used to perform virtual testing of the
composite decks under both quasi-static and fatigue loading
conditions. The GENOA progressive failure code succeeded in
predicting not only the stresses and strains, but also the major
mode of failure observed during the full-scale laboratory tests
(Figure 33). The numerical code was also used to design and
verify the efficiency of emergency repair system for potential
damage that may occur during service due to impact loading
caused by a drop of a container from a truck. Figure 34 shows
the repair simulated model. As shown in Figure 35, the simple
proposed repair system was not only successful in restoring the
original capacity of the damaged deck, but also exceeded the
original capacity by about 25%. Based on the results of both the experimental and theoretical
verification results, the composite deck design were revised and
optimized. The final design and specifications documents were
prepared and tender documents were issued by Caltrans for
qualified contractors. Due to the heavy truck traffic of the Schuyler
Heim Bridge, in and out the harbor, it was decided to perform the
construction in two consecutive weekends for minimum traffic
interruption. Figure 36 presents several photographs that were
taken during the construction of composite deck modules. In
order to monitor the long-term performance of the composite
deck, strain gages were applied to different sections and are
currently being monitored.
Chemung county bridge, New York, USA: New York DOT
has selected the composite deck solution to replace the old deck
of the Chemung County Bridge (Figure 37). This steel truss bridge
was originally built in 1940, with a span length of 140 feet (42.7
meters) and a width 24 feet (7.32 meters). The average daily traffic
on this bridge (AADT) is 3250 with 7% of this volume is trucks.
The engineers in New York DOT Region 6, decided to adopt the
FRP composite light weight solution (Figure 38), in addition to
repair and painting of steel truss members. After the addition of
the FRP bridge deck, the load rating of the bridge raises from the
original inventory of HS12 (22 tons) with operating capacity of
HS 18 (33 tons) to an inventory of HS 23 (42 tons) with operating
capacity of HS 34 (61 tons).
Smith road bridge, Ohio, USA: This was Ohio’s first all
Fatigue damages of the lift-span of the Schuyler Heim highway
steel bridge, Long Beach, California, USA.
Ultimate failure mode of pultruded sandwich core beams:
(a) “Real” Test (b) “Virtual” Test.
composite bridge that was installed in July 8, 1997. Martin
Marietta Composites (MMC) designed and manufactured the
bridge that was constructed from FRP deck and U-shaped
composite beams. This composite bridge has a span of 33 feet (10
meters), a width of 24 feet (7.32 meters), a depth of 2 feet and 9
inches (84 cm) and weighted less than 22,000 pounds (9,980 kg).
The sandwich composite deck consisted of pultruded composite
tubes between two face sheets. The pultruded tubes run parallel
with the traffic direction. Three U-shaped composite beams were
used to support the sandwich deck (Figure 39). Figure (40)
shows the different stages of construction of the bridge.
Fiberline all-composite cable-stayed, Denmark: A similar
all-PFRP-composite pedestrian cable-stayed bridge was built by
Fiberline Company (Kolding, Denmark) crossing a busy rail line,
and was officially opened on 18 June, 1997 (Figure 41). Although,
the construction work was restricted to only a few hours
during weekend nights due to the busy railway line restricted
installation work to only, the bridge was fully installed in only
three short nights. The short installation time has illustrated the
clear advantages of composites.
Pontresina bridge, Switzerland: In 1997, a 25 meters allcomposite
bridge was installed in the mountainous region of
Pontresina in Switzerland (Figure 42). The reasons behind the
choice of this system is the light weight feature of composite
that made it possible to transport the bridge to the mountain
area by helicopter and the ease of disassembling during spring
season in order to avoid damming and flooding when the melting
water carries stone and gravel through the riverbed that used to
damage other bridges that were used in the past at that location.
The bridge was transported in two sections, each measuring
12.5 meters (41 feet) one section was glued while the other was
bolted. The total weight of the bridge is 3,300 kilograms, with a
load carrying capacity of 500 kg/m2, in addition to a 1-ton snow
clearing vehicles allowance.
Numerical simulation for developing the emergency repair system for the Schuyler Heim Bridge FRP Deck.
P-δ Curves for original (undamaged) and repaired FRP deck specimens.
Field installation of the hybrid composite bridge deck at the Schuyler Heim bridge site, Long Beach, California, USA.
Installation of all-composite bridge deck of NY 367 over
Bentley Creek, Chemung County, New York, USA.
Self-weight comparison between existing and new FRP composite
deck of the Bentley creek, New York, USA.
The smith road bridge all-composites bridge, Ohio, USA.
Development of codes, standards and design
In recent years, the construction industry started to realize
the potential of using polymer composites in construction
applications. Unfortunately, the construction industry and the
civil engineers were faced with tremendous amount of difficulties
to utilize these materials in the same manner they are used to for the conventional material such as steel, concrete and wood. The
major obstacle is the lack of design standards and authoritative
codes for the use of these materials in construction applications.
Despite the fact that there is a great deal of research and
application information available from the aerospace industry for
the past four decades or so, still the civil engineers are searching
for ways to convince them with the reliability, applicability and
the structural efficiency of such materials. For any structural
system, design standards are one the essential requirements
for professional engineers acceptance. The following paragraph
describes the effort of different professional organizations in
publishing technical documents in this area.
Construction stages of the smith road bridge all-composites
bridge, Ohio, USA.
The fiberline all-composite cable-stayed in Denmark.
Transportation and construction of pontresina bridge, Switzerland.
United States of America (USA)
The American Society of Civil Engineers (ASCE), American
Concrete Institute (ACI), American Association of State Highway
and Transportation Officials (AASHTO), and the International
Code Council (ICC), have been the leading organizations in USA
in developing codes, specifications, design guides and national
standards in the area of composites for civil infrastructure
applications. The following paragraphs describe the efforts of
The American Society of Civil Engineers (ASCE): Since
1960’s, the ASCE has been involved in developing several
engineering documents dealing with both unreinforced and
fiber reinforced polymers (FRP) materials and systems. In 1984
, the ASCE Structural Plastics Design Manual (SPDM) was
published (1984) by the Plastic Research Council of the Materials
Division of ASCE. Starting late 1980’s, as the demand and the
acceptance of FRP materials increased, the ASCE recognized the
need for more developments in this field. Jointly, with the Society
of Plastics Industry (SPI), a long-rang, multi-phase program
was established in early 1990’s. The ultimate goal of this joint
program is to develop accepted standards for structural design,
fabrication and erection of FRP composite systems. In 1995,
the Pultrusion Industry Council (PIC) of SPI sponsored the first
phase of this program to develop a design draft standard or a
‘prestandard” document with a view to process the prestandard
upon completion as an ASCE national consensus standard in
accordance with the rules of the American National Standard
Institute (ANSI). In late 1995, ASCE awarded Phase I of this
project to Chambers Engineering, p.c. (as the General Contractor)
and the first author (as the Subcontractor) to undertake a oneyear
startup and planning phase of the multi-phase standard
program. The scope of work of Phase I was to i) Survey and
evaluate existing design and martial information. This task
included researching both published and unpublished technical
literature, government and university reports, performance data,
standards and specification documents (ASTM, ACI, ASCE, JSCE, Eurocode, Canada,..), manufacturer’s materials data, and current
practice relative to the use of FRP composites, ii) development of
a computerized database containing the relevant and evaluated
useful technical information, iii) using this database, identify gaps
in knowledge that may impede promulgation of the standard, and
finally, iv) developing the prestandard outline through defining
the approach including recommended design philosophy and
relationship of the ASCE design standard with other martial or
industry standards such as AASHTO, ASTM, ISO, ICC. The second
phase of this program is in progress that aims at establishing a
Standard LRFD Design of Pultruded Fiber reinforced Polymer
(FRP) Structures. Lately, the American Society of Civil Engineers
(ASCE) has published a Structural Design Manual (MOP 102) on
FRP composite connections (www.asce.org). The manual consists
of ten chapters covering a wide range of design topics related to
joining PFRP frame structures (Mosallam, 2011).
American Concrete Institute (ACI): In 1993, the American
Concrete Institute (ACI) realized the potential of the polymer
composites in concrete applications. For that reason, a new
committee (ACI 440) was formed to answer the needs of this
new industry and to provide guidelines for design, specifications,
and applications of polymer composites as external and internal
reinforcement systems. Due to the rapid increase of new polymer
composite products and applications, the ACI 440 committee
was divided to several subcommittees focusing on different
design and application aspects of polymer composites in
concrete applications. This includes subcommittees on internal
reinforcements (FRP rebars), FRP Prestressing, FRP external
repair, education, and others. One of the active subcommittees
is the ACI-440 subcommittee on FRP External Reinforcements
(ACI 440F). The information presented in ACI 440 documents
will assist the structural engineer in properly selecting and
designing an optimum and reliable FRP system. The documents
also describe conditions where FRP strengthening is beneficial
and where its use may be limited. The following are the current
ACI 440 publications that can be obtained from the American
Concrete Institute web site: www.concrete.org
ACI 440R-07 “Report on Fiber-Reinforced Polymer (FRP)
Reinforcement for Concrete Structures,” ACI Committee
440, American Concrete Institute, Farmington Hills, Mich.,
ACI 440.1R-06 “Guide for the Design and Construction
of Structural Concrete Reinforced with FRP Bars,” ACI
Committee 440, American Concrete Institute, Farmington
Hills, Mich., (2006), 44p.
ACI 440.5-08 “Specification for Construction with Fiber-
Reinforced Polymer Reinforcing Bars,” ACI Committee
440, American Concrete Institute, Farmington Hills, Mich.,
ACI 440.6-08 “Specification for Carbon and Glass
Fiber-Reinforced Polymer Bar Materials for Concrete
Reinforcement,” ACI Committee 440, American Concrete
Institute, Farmington Hills, Mich., (2008), 6p.
ACI 440.3R-04 “Guide for Test Methods for Fiber Reinforced
Polymers (FRP) for Reinforcing and Strengthening Concrete
Structures,” ACI Committee 440, American Concrete
Institute, Farmington Hills, Mich., (2004), 40p.
ACI 440.2R-08 “Guide for the Design and Construction of
Externally Bonded FRP Systems for Strengthening Concrete
Structures,” ACI Committee 440, American Concrete
Institute, Farmington Hills, Mich., (2008), 76p.
ACI 440.7R-10 “Guide for the Design and Construction
of Externally Bonded FRP Systems for Strengthening
Unreinforced Masonry Structures” ACI Committee 440,
American Concrete Institute, Farmington Hills, Mich.,
ACI 440.4R-04 “Prestressing Concrete Structures with FRP
Tendons,” ACI Committee 440, American Concrete Institute,
Farmington Hills, Mich., (2004), 35p.
International Code Council (ICC): In 1997, the International
Code Council, ICC of USA (formerly called International Conference
for Building Officials, ICBO) Evaluation Service (ES) produced
two acceptance criteria related to repair and rehabilitation of
reinforced concrete and masonry structures; namely AC125
and AC 178 that are available at the ICC-ES website (icc-es.org).
Unlike the ACI current proposed document, the AC125 focused
more on applications related to seismic design.
American Association of State Highway and
Transportation Officials (AASHTO): For pedestrian bridge
applications, the American Association of State Highway and
Transportation Officials has published a guide specifications for
designing such bridges 2008. In 2009, AASHTO published an LRFD
Bridge design guide specifications for GFRP-reinforced concrete
bridge decks and traffic railings. Copies of these documents can
be obtained at the AASHTO website: www.transportation.org
In Japan, the Research Committee on Continuous Fiber
Reinforcing Materials published a recommendation for design and construction of concrete structures using continuous fiber
reinforcing materials (1997) . Sonobe Y, et al.  provided
an English translation of the Japanese Design Guidelines of FRP
Reinforced Concrete Building Structures. In 1999, the, Japan
Building Disaster Prevention Association (JBDPA)  published
a design and construction guidelines for the use of FRP composites
in seismic retrofitting of existing RC Buildings. Also, the Japanese
Society of Civil Engineers (JSCE) established a subcommittee
on FRP Bridges was and has published in 2004  a technical
report titled “FRP bridges – technologies and their future”. Some
of these documents are accessible to public at:
In Canada, major efforts in establishing design and
specifications for FRP composites in construction have been
have been accomplished. The Canadian Standards Association
has taken the lead in this effort by developing two documents
focusing on FRP composites; namely (i) Design and Construction
of Building Components with Fibre-Reinforced Polymers (2007)
, and (ii) Specification for Fibre-Reinforced Polymers (2010)
. For bridge applications, design information on composites
was included in the Canadian Highway Bridge Design Code (2006)
. These documents can be obtained through the Canadian
Standards Association web site: http://shop.csa.ca/. Several
documents were also developed by the ISIS Canada Research
Network (ISIS). The following are some of the ISIS published
design related publications that can be obtained from ISIS web
ISIS Design Manual No. 2 - Guidelines for Structural Health
Monitoring, ISIS Canada
ISIS Design Manual No. 3 - Reinforcing Concrete Structures
with Fibre Reinforced Polymers (FRPs), ISIS Canada
ISIS Design Manual No. 5 - Prestressing Concrete Structures
with FRPs, ISIS Canada
ISIS Product Certification - Specifications for FRP Product
Certification of FRPs as Internal Reinforcement in Concrete
Structures, ISIS Canada
ISIS Durability Monograph - Durability of Fibre Reinforced
Polymers in Civil Infrastructure, ISIS Canada
In Europe, several organizations have been working on
developing standard and technical documents related to FRP
composites in construction applications. One of the active
organization is fib (fédération internationale du béton or the
International Federation for Structural Concrete). Two bulletins
(Bulletin 14 and Bulletin 35) were published by fib in 2001 
and 2006 . These documents can be obtained from the fib
web site: http://www.fib-international.org/publications/fib
A technical document on design and construction of structures
made of thin FRP pultruded elements was published in 2002 by the European Committee for Standardization (CEN), Brussels,
Belgium. A copy of this document can be found at: http://www.
The EUROCOMP Design Code and Handbook was developed
and published (Clark, ed. 1996). In Germany, the German
Institute for Building Technology developed guidelines for the
use of FRP composites for strengthening RC structures that was
published in 1998. The UK Concrete Society published guidelines
for design and inspection of RC members strengthened with FRP
Middle East & North Africa
The first design code for FRP composites in Strengthening
and Repair applications was developed few years ago in Egypt.
The code is published by the Housing and Buildings National
Research Center (HBRC). Copies of this code can be obtained
through HBRC website: http://www.hbrc.edu.eg/en/Home.html
Funded by the Australian Federal Government, the
Queensland State Government, with additional support from a
range of industry stakeholders, an initiative to establish a Fibre
Composites Design and Development (FCDD) program was
initiated with an ultimate goal of developing a design code of
practice for FRP composites. Similar to the ICC-ES certification
program in USA, another initiative to develop a National
Constituent Certification Scheme (NCSS) to provide a mechanism
for evaluating and accepting different types of FRP composites
systems for infrastructure applications.
International Organization for Standardization (ISO)
Three ISO documents were published related to FRP
ISO/DIS 14484, Performance Guidelines for Design of
Concrete Structures using Fibre-reinforced Polymer
ISO 10406-1 Fibre-reinforced polymer (FRP) reinforcement
of concrete - Test methods - Part 1: FRP bars and grids.
ISO 10406-2 Fibre-reinforced polymer (FRP) reinforcement
of concrete - Test methods - Part 2: FRP sheets.
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- Mosallam A (2007) Structural evaluation and construction of FRP composites strengthening systems for the sauvie island bridge. J Compos Constr 11(2): 236-249.
- Polyzois D, Kell JA (2007) Repair and rehabilitation of wood utility poles with fibre-reinforced polymers. Canadian Journal of Civil Engineering 34(1): 116-119.
- Lopez-Anido R, Michael A, Sandford TC (2003) Experimental characterization of FRP composite-wood pile structural response by bending tests. Marine Structures 16(4): 257-274.
- Tingley D (1999) Reinforced plastic computability with wood composites. Proceedings, 5th ASCE Materials Engineering Congress, pp. 108-115.
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- Mosallam AS (2007) Out-of-plane flexural behavior of unreinforced red brick walls strengthened with FRP composites. Composites Part B: Engineering 38(5-6): 559-574.
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- Petersen RB, Masia MJ, Seracino R (2010) In-plane shear behavior of masonry panels strengthened with NSM CFRP strips II: finite element model. J Compos Constr 14(6): 764-774.
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- Haroun MA, Mosallam AS, Feng MQ, Elsanadedy HM (2003) Experimental investigation of seismic repair and retrofit of bridge columns by composite jackets. Journal of Reinforced Plastics and Composites 22(14): 1243-1268.
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- Feo L, Mosallam AS, Pennaa R (2013) Mechanical behavior of web-flange junctions of thin-walled pultruded i-profiles: an experimental and numerical evaluation. Composites Part B: Engineering 48: 18-39.
- Mosallam AS (2011) Design for FRP composite connections. ASCE Manuals and Reports on Engineering Practice MOP#102, American Society of Civil Engineers (ASCE), Reston, Virginia, USA.
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