Carbon Fiber (FRP) used for structural strengthening. It’s 5 to 10 times stronger than steel, light weight and corrosion resistant. The ASME PCC-2 code new standard includes carbon fiber as an acceptable repair and strengthen system for steel pipes.
4. What Are FRP Composites?
Reinforcing Fiber
(Glass, Carbon, Kevlar, etc.)
Interphase Coupling Agent
Polymer Resin Matrix
5. Advantages of Carbon Fiber
• High Strength (400 KSI Tensile)
• Low Weight (less than 0.5 pounds per sq. ft.)
• Corrosion Resistance (pH 2 – pH 13)
• Thermal Compatibility
• Excellent Fatigue Behavior
• Non-conductive (glass), Conductive (carbon)
• Speed of Construction
• Low Cost
6. Engineering Support
• Full range of support
• Software assistance
• Full engineering capabilities including
stamp
• Minor support and design assistance
7. Examples of Applications
• PCCP hoop strengthening
• Missing/under designed reinforcement
• Seismic strengthening
• Cutting or drilling of structural members
• Low cylinder breaks
• Adding capacity
• Underground/Sewer/Water Infrastructure
• Fatigued Members
• Corrosion Mitigation
• Steel Pipe Repair & Strengthening
9. Cholla Power Plant
Situation:
The 66" circ line had experienced enough wire breaks
that a possible rupture was a major concern. The original
repair was only 40-60 linear feet depending on the
condition of the pipe. We needed to be able to restore the
pressure bearing capacity of the circ line, the overburden
was only 8’.
Challenges:
Time restraint was a major factor, this job there was only
a small window of time to do the entire job. The prep
work for the job was limited to only within 2 weeks. To
remove and replace the line would have involved too
much time and disruption of the existing above ground
infrastructure. Likewise external tensioning would have
taken too long with too much disruption.
10. Cholla Power Plant
Solution:
We went ahead and came up with a comparable solution
that would not affect any of the above ground
infrastructure and still provide the needed support.
Carbon fiber was installed in two layers of 20 oz
unidirectional in a hoop direction.
Conclusion:
The original 40 linear feet was done in 2 days. After the
completion of the work, APS requested us to complete
an additional 120 lf. We mobilized within 72 working
hours and completed the additional 120 lf within 5 days.
11. •San Juan Power Plant
Situation:
Wire breaks in the 10' diameter pipes severely limited
the capacity of the pipe to with stand internal pressure.
The goal was to restore the capacity of the pipeline.
Challenges:
All work needed to be done within the time frame of the
shut down of 3 weeks for the # 3 circ line and 3 days for
the #4 circ line. Replacement was far too costly and too
much down time. Steel lining would reduce the flow,
cause future corrosion, and would have high
mobilization costs.
12. •San Juan Power Plant
Solution:
It was decided to install 20 oz of unidirectional carbon
fiber in hoop direction, because this solution can be done
quickly and with little invasiveness. Another supporting
reason was because the risk of corrosion would be
nonexistent.
Conclusion:
Before installation took place it was discovered that
there were severe cracks where the carbon fiber was to
be installed in the hoop direction. 20 oz of carbon fiber
was installed perpendicular to the cracks before
installing in the hoop direction to help maintain the
integrity of the pipe. The job was completed in the time
required and is still functioning today.
13. Missing/Under designed reinforcing
• Downtown Lofts
• Missing rebar in High Rise
• Column cage missing
• Scottsdale office building floor
strengthening
14.
15.
16. B of A Bank Renovation
This building in Old Town Scottsdale was being renovated to provide a new home
for a B of A Bank branch. The bank vault was being installed on the first floor
slab over a parking garage below. The slab needed to be strengthened to carry
the load of the vault.
17. B of A Bank Renovation
Existing cracks in the slab were first epoxy injected then carbon fiber fabric
was installed on the top of the slab.
18. B of A Bank Renovation
The double T’s were then strengthened by adding carbon fiber laminates strips
on the under sides of the T stems then the entire T was wrapped with carbon
fiber fabric.
This engineered solution provided the additional capacity to carry the
additional load of the new vault.
20. AmeriSchools Academy
• The City of Yuma dictated that
AmeriSchools Academy, built of CMU
masonry, be reinforced to protect the
students, teachers and workers in case of
an earthquake.
21. The Solution
After several solutions were investigated, it was determined that seismic
reinforcement could best be achieved with carbon-fiber composites applied to the
exterior and interior wall surfaces.
North side of building after sandblasting to Front entrance is shown with windows
remove paint in areas where carbon-fiber is removed and surface sandblasted, now ready
to be installed. for 2 layers of fabric to be installed
22. The Results
The application of carbon-fiber fabrics and laminates proved to be the least
expensive and most effective way to provide seismic reinforcement. The client was
very satisfied with the product and job coordination. Realizing the challenges the
crew faced doing this in the summer when the temperature was between 110 and
120 degrees. The job was completed in time for the school to reopen for classes
the end of July.
Shown below the crew is installing This shows the front entry after the
carbon-fiber laminates on the interior application of bi-directional fabrics.
walls and openings. Stucco was later added then painted.
25. DEMA Renovation
• On this renovation project (10) 6” pre-cast
hollow-core floor planks had numerous
penetrations through them for utilities.
Many of them were old existing and
several new penetrations were created for
new plumbing. In many cases these
penetrations had severed the post tension
cables.
26. The Solution
Fill the old penetrations that were not to be reused. Install 4” wide carbon fiber
laminate strips to the underside of the planks in the areas where the penetrations
had been filled.
At the areas where the new plumbing was protruding we overlaid 12” wide carbon
fiber fabric strips in a cross hash pattern over the laminate going 24” past the
plumbing on all sides.
27. The Results
The strength lost because of the penetrations and the post tension cables being
cut was restored. This allowed the restoration to continue at a great cost saving
over replacing the floor planks. Which would have been an enormous construction
issue at best.
28. The Summit at Copper Square
• This 23 story concrete shear wall
residential building had 35 spandrel
beams that were cored for pipe sleeves
below the approved zone per criteria given
by the engineer of record. This caused a
lost of capacity of 35 kips in downward
shear.
29. The Solution
Install one layer of uni-directional carbon fiber fabric the full width of the beams and
wrapping the complete beam. It was determined that any beam with a core 8 ½” or
less from the bottom of the beam need carbon fiber support. This replaced the 35
kips structural strength lost by the cores while maintaining the ceiling height in the
hallways.
30. The Results
Because some of the plumbing had already been installed the fabric had to be cut
to allow the installers to wrap the fabric around the pipes. A second layer of fabric
was installed over the cuts in a horizontal direction to prevent lose of strength from
the cuts. The job was completed in 2 weeks and the contractor was able to get
back on schedule with construction.
34. Roger Road Treatment Plant
Situation:
The digestive gasses eroded the existing concrete
columns and deteriorated the existing reinforcement.
Challenges:
The sludge digester needed to be kept free of rocks and
pebbles. The floor of the digester was slanted making
scaffolding a challenge and more difficult to keep debris
out.
35. Roger Road Treatment Plant
Solution:
Installers from the Arizona Repair Masons' Specialty
Crew reinforced deteriorated columns with carbon fiber
composites inside the drained digester tank of the
sewage treatment plant. Damaged rebar was augmented
with fiberglass rebar.
Columns being wrapped with Carbon
fiber laminates in order to reinforce
the eroded areas.
Conclusion:
Company was happy with the end results of restoration
to the columns.
37. Added Touch Warehouse
Badly spalled and deteriorated columns due to years of water coming
from the scuppers with no down spouts.
38. Added Touch Warehouse
•After the concrete repairs were made carbon fiber was installed to regain the
strength lost from the corroded rebar.
•The owner wanted the repaired columns to match the appearance of the other
columns on this structure.
•After the carbon fiber was installed sand was broadcast on the columns for a
base to apply stucco.
40. CityScape Garage
• The cracked and spalled concrete was removed to provide a solid
strata for the repair mortar and the exposed rebar was cleaned and
treated with a corrosion inhibitor.
41. CityScape Garage
•After the concrete repairs were made carbon fiber was installed to confine the
repair and regain the loss of strength due to the corroded rebar.
43. Central Stores—City of Phoenix
Situation:
The wood beams that support the roof had been
deflecting over a few years. The problems are
exacerbated with the ponding of rain water in the
dips created from the deflections. There were
approximately 190 beams that required
strengthening. The Owner (The City of Phoenix)
wanted us to arrest any continued deflections and
increase the margin of safety for the users.
Challenges:
Work in the space was to continue without
shutting down the users.
Air conditioning replacement was going on
simultaneously which caused poor ventilation.
44. Central Stores—City of Phoenix
Solution:
Carbon fiber laminate reinforcing with
fiberglass fabric stirrups were used. The
Carbon laminates provide continuous
adhesive reinforcing. The laminates were
placed in the middle 8' of the beams,
where the deflection was the greatest on
the tension face. The glass fabrics were
used to eliminate shear stresses on the
ends and to transfer the tensile force of
the laminates up through the natural axis.
45. Central Stores—City of Phoenix
Conclusion:
Arizona Repair Masons helped insure that the
original engineering was adequate to meet the
loads with acceptable deflection by insisting
that the original calcs be checked. Workers
used respirators during operations. The
overstress on the beams was reduced to less
than .07% and the ponds on the roof were
filled in with foam to shed future water.