Structural strengthening, restoring and adding capacity is an integral part of today’s concrete repair industry. Structural strengthening may be required for increasing load capacity of beams, columns, walls, and/or slabs, seismic retrofitting, supporting additional live or dead loads not included in original design, to relieve stresses generated by design or construction errors, or to restore original load capacity to damaged structural elements.

1. EPA Infrastructure Pvt. Limited
Structural Strengthening
B-267/268, North Ex Mall, Sector 9, Rohini,
New Delhi - 110085
Tel No: +91-11-47068151/52/56
Email: info@epa-infrastructure.com

2. Structural Strengthening
Structural strengthening, restoring
and adding capacity is an integral
part of today’s concrete repair
industry. Structural strengthening
may be required for increasing load
capacity of beams, columns, walls,
and/or slabs, seismic retrofitting,
supporting additional live or dead
loads not included in original design,
to relieve stresses generated by
design or construction errors, or to
restore original load capacity to
damaged structural elements.

3. Advanced Composite Material
Fiber reinforced polymer (FRP) composite
systems are used to strengthen a wide
variety of structures for flexure, shear,
axial loads, and seismic upgrading. Both
Glass FRP (GFRP) and Carob FRP
(CFRP) are used in these applications
with CFRP being used for most structural
applications.
Fiber reinforced polymer (FRP)
composites have been used for decades in
aerospace and manufacturing applications
where low weight, high tensile strength,
and non-corrosive structural properties
are required. In civil engineering
applications, CFRP has proven to be
extremely effective as externally bonded
reinforcement. CFRP materials are
successful because they exhibit low creep,
and compared with steel, are thinner,

4. Advantages
Quick completion time
Cost effective when compared with the remove and replace option
No additional dead load added to the structure
Minimal access to work area required
No heavy equipment is involved
Corrosion resistant system
No maintenance required

5. Structural Steel
Often structural or steel plates are added
to concrete structures to allow them to
carry additional loading. In most
applications the steel plates are bonded to
the concrete by means of epoxy adhesives,
and in addition to bonding, it is a good
practice to also bolt the steel plates to the
concrete.
While this process is relatively labour and
equipment intensive, there are many
applications where the use of steel plates
is the best alternative for structural
strengthening. Typical applications for
bonded steel strengthening are the ones
where the use of advanced composite
materials would be prohibitive due to
their higher costs, and/or where traffic or
other type of wear would damage a FRP

6. Advantages
Low cost (as long as no special shape fabrication required)
Vandalism and wear resistant

7. Post-Tensioning Strengthening
For strengthening pre-stressed concrete beams or
slabs, simple externally bonded strengthening
systems may not be sufficient. In these situations
the strengthening system may need to be
tensioned to provide an active strengthening
system and be able to enhance the load carrying
capacity of the concrete structure in conjunction
with the existing built-in pre-stressing system. In
most cases the post-tensioning system is designed
with the following external components: fixed
anchorage system located towards each end of
the beam/slab, and post-tensioning cable that
tensioned between the two anchors then locked in
a tensioned state. The tensioning cable can be
regular high tensile multi-strand steel, rigid
carbon fiber rod, or carbon fiber fabric. The
post-tensioning cable can be bonded or unbonded along its entire length. The end
anchorage system can be made of either concrete
that is doweled into the existing concrete, or
could be manufactured of structural steel that is
bolted to the structure.

8. Advantages
Increases load capacity of the structure to design specifications
Cost effective alternative to the only other option: remove and replace
Minimal construction time required
Requires minimal or no disruption to traffic/plant operation

9. Thank You

10. Thank You