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Contact: Mukhtar Homam

Publications in Public Domain

M.A.S.c Thesis (2000)

DURABILITY OF FIBRE REINFORCED POLYMERS (FRP)USED IN CONCRETE STRUCTURES

Ph.D. Thesis (2005)

Fibre Reinforced Polymers (FRP) and FRP-Concrete Composites Subjected to Various Loads and Environmental Exposures

Durability of Fibre Reinforced Polymers Used in Concrete StructureS (2000)

S. M. Homam, S. A. Sheikh

P. Collins, G. Pernica, and J. Daoud

Use of Fibre Reinforced Polymers in new and existing structures is increasing at a rapid pace. The effectiveness of structural upgrade in the short-term tests has been demonstrated repeatedly in the laboratory tests and field applications. However, the long term durability of the FRP and FRP-reinforced concrete has not been investigated to a point that a designer can suggest the application of FRP with the same confidence as the traditional materials.

In this paper, selected results from an extensive test program are presented in which the durability of FRP materials and FRP-reinforced concrete was investigated. The environmental parameters to which the specimens were subjected included freeze-thaw cycling (50, 100, 200, and 300 cycles), UV radiation (1200, 2400, and 4800 hours), temperature variation (28, 56, 112, and 336 cycles), NaOH solutions with pH 10 and pH 12 concentrations (7, 14, 28, and 84 days), and moisture (7, 14, 28, and 84 days). Specimens comprised FRP coupons and FRP-FRP single lap bond specimens. The tests carried out on the specimens examined the influence of various environmental conditions on their mechanical properties such as stress-strain characteristics and bond between FRP and FRP. Results to-date indicate that the exposure to most of the environmental conditions has minimal effects on the properties tested during this experimental program. Freeze-thaw cycles and moisture exposure seemed to be the two environmental conditions with noticeable effects on the bond properties of single lap bonded specimens.

Proceedings of the 3rd International Conference on Advanced Composite Materials in Bridges and Structures, Ottawa, Canada, 15-18 August 2000, 751-758.

DURABILITY OF FIBRE REINFORCED POLYMER (FRP) WRAPS AND EXTERNAL FRP-CONCRETE BOND (2001)

S. Mukhtar Homam and Shamim A. Sheikh

And P. K. Mukherjee

Carbon and glass Fibre Reinforced Polymers (CFRP and GFRP) have proved very effective in restoring and upgrading the performance of concrete structures. However, concerns about the durability of FRP’s have been a major obstruction to a rapid growth in their application in concrete structures. For a designer to suggest the application of FRP with the same confidence as the traditional materials, it is vital to know how these new materials perform when exposed to severe environments.

In this paper, selected results from an extensive test program are presented in which the durability of FRP-reinforced concrete was investigated. The environmental parameters to which the specimens were subjected included freeze-thaw cycling, temperature variation, and NaOH solutions with pH 10, pH 12 and pH 13.7 concentrations. Specimens comprised FRP wrapped concrete cylinders and FRP bonded concrete prisms. The tests carried out on the specimens examined the influence of various environmental conditions on the confining effects of FRP wraps and performance of FRP-to-concrete bonds. Results to-date indicate that the exposure to low alkaline environments has minimal effects on the properties tested during this experimental program. High alkaline, freeze-thaw cycles, and temperature cycles seemed to be the environmental conditions with noticeable effects on the bond properties.

Proceedings of the 3rd International Conference on Concrete under Severe Conditions, Vancouver, Canada, 18-20 June 2001, 1866-1873.

A Decade of Performance of FRP-Repaired Concrete Structures (2004)

Shamim A. Sheikh and S. Mukhtar Homam

During the last ten years, several concrete structures were repaired or

strengthened with glass and carbon fibre reinforced polymers (GFRP and CFRP). These applications varied from a concrete platform in an oil refinery to bridge columns and bridge culverts along Canada’s major highways to high-rise apartment and condominium buildings and a restaurant concrete structure located on the US West coast with its columns and beams submerged in the Pacific Ocean. The repaired components included slabs, beams and walls in addition to the columns. Most of the repairs were carried out to fix the damage caused by the combined effects of weather, environmental hazards such as chemical attacks and overloads. Strengthening was carried out to increase the load carrying capacity of the structural components either to resist the increased load or to compensate for the deficiencies in design and construction. Some of these structures were instrumented to measure deformations and the corrosion rate before and after the repair. Visual inspection was also carried out routinely over the years. All the structures have been found to behave in an excellent manner. No significant problems have been encountered in the performance of any of these structures. This paper describes brief details of repair of some of these structures and their performance and covers a period of about ten years.

Proceedings of ISIS-SHM 2004 Workshop, Winnipeg, Manitoba, Canada.

A Decade of Performance of FRP-Repaired Concrete Structures (2004)

Shamim A. Sheikh and S. Mukhtar Homam

During the last ten years, several concrete structures were repaired or

strengthened with glass and carbon fibre reinforced polymers (GFRP and CFRP). These applications varied from a concrete platform in an oil refinery to bridge columns and bridge culverts along Canada’s major highways to high-rise apartment and condominium buildings and a restaurant concrete structure located on the US West coast with its columns and beams submerged in the Pacific Ocean. The repaired components included slabs, beams and walls in addition to the columns. Most of the repairs were carried out to fix the damage caused by the combined effects of weather, environmental hazards such as chemical attacks and overloads. Strengthening was carried out to increase the load carrying capacity of the structural components either to resist the increased load or to compensate for the deficiencies in design and construction. Some of these structures were instrumented to measure deformations and the corrosion rate before and after the repair. Visual inspection was also carried out routinely over the years. All the structures have been found to behave in an excellent manner. No significant problems have been encountered in the performance of any of these structures. This paper describes brief details of repair of some of these structures and their performance and covers a period of about ten years.

Proceedings of ISIS-SHM 2004 Workshop, Winnipeg, Manitoba, Canada.

DURABILITY OF FIBRE REINFORCED POLYMERS (FRP) EXPOSED TO HIGH TEMPERATURES AND GAMMA RADIATION (2007)

S.M. Homam and S.A. Sheikh

Effectiveness of fibre reinforced polymers (FRP) in repair and upgrade of concrete structures has been demonstrated repeatedly in short-term laboratory tests and field applications. FRPs have superior strength- and stiffness-to-weight ratios and are easy to use but the interest in FRP is mainly driven by the fact that they can prevent the corrosion related problems that are associated with reinforcing steel. One of the newer areas of interest in application of FRP is its potential for repairing and strengthening of nuclear containment structures and oil refineries. However, the data on the durability of FRP subjected to various environmental exposures in such structures is still lacking. The lack of durability information has been one of the main drawbacks in the industry-wide use of FRP by engineers and designers.

This paper evaluates the durability of room-temperature-cured FRP and FRP-FRP bond subjected to simulated nuclear power plant environment. The exposure environment included gamma radiation, loss of coolant accident (LOCA) scenario, and sustained and cyclic high temperatures. The behaviour of FRP-FRP bonds under stress and subjected to increasing temperature was also studied.

It was observed that FRP and FRP-FRP bonds have good resistance to almost all of the exposures studied. However, FRP-FRP bonds were unable to maintain their load carrying capacity when they were subjected simultaneously to stress (30% of ultimate) and temperatures approaching the glass transition temperature of epoxy.

Proceedings of the 3rd International Conference on Durability and Field Applications of Fibre Reinforced Polymer (FRP) Composites for Construction – CDCC 2007, Quebec City, Quebec, Canada, May 22 –24, 2007, 185-192.

LONG-TERM PERFORMANCE MONITORING OF GFRPREPAIRED BRIDGE COLUMNS (2007)

Shamim A. Sheikh and S. Mukhtar Homam

Concrete structures in most parts of Canada are subjected to severe environmental conditions. This combined with the use of de-icing salt on roads and highways cause extensive degradation in transportation structures. Several columns in various bridges, damaged primarily by the corrosion of steel, were repaired with glass fibre reinforced polymers (GFRP) in and around Toronto in mid-nineties. One of these bridges is located along Highway 401 over Leslie Street. The lab study indicated that the axial load carrying capacity of the damaged columns was reduced by about 20% due to corrosion of steel and loss of concrete cover. Three types of grouts were used to build the columns to their original shape before wrapping them with GFRP. The grouts were based on regular cement, non-shrink cementitious material or expansive cement.

Performance monitoring for over 11 years has shown that the repaired columns

have been providing excellent service without any problems. No deteriorating has been observed in the GFRP or the columns during this time. Monitoring of corrosion activity indicated that the rate of corrosion in GFRP-repaired columns and the associated risk of corrosion have reduced significantly over time. This paper provides a brief overview of the background research work, repair details of the bridge columns and results from the field monitoring.

Proceedings of the 3rd International Conference on Structural Health Monitoring of Intelligent Infrastructure - SHMII-3 2007, Vancouver, British Columbia, Canada, 13-16 November 2007.

Durable Retrofitting of Concrete Structures (2010)

S. A. Sheikh and S. M. Homam

Ageing, adverse environmental effects and stricter provisions of new design codes have rendered numerous reinforced concrete structures in the world deficient. Their upgrade is a major engineering activity that needs special attention. Retrofitting these structures with fibre reinforced polymers (FRPs) is becoming popular as an alternative to conventional repair techniques.

Second International Conference on Sustainable Construction Materials and Technologies, Università Politecnica delle Marche, Ancona, Italy, June 28 - 30, 2010.

Fiber-Reinforced Polymers Exposed to Nuclear Power Plant Environment (2013)

S. Mukhtar Homam and Shamim A. Sheikh

Abstract: The effectiveness of fiber-reinforced polymers (FRP) in structural upgrade has been demonstrated repeatedly in short-term laboratory tests and field applications. Consequently, the level of interest in exploring the potential applications of FRP in various types of structures and environments has increased. One of the potential areas of application of FRP is in nuclear power plants (NPP). However, there is very little research data available on the durability of FRP subject to an NPP environment. This paper reports the results from an experimental program aimed to address this knowledge gap. The study involved testing a total of 84 specimens consisting of FRP coupons, FRP-FRP single lap-bonded specimens, and FRP-bonded concrete prisms for their performance before and after exposure to gamma radiation. Both glass and carbon FRPs were included in this study. The specimens were tested for FRP tensile, FRP-to-FRP bond, and FRP-to-concrete bond properties. Results showed that the tensile and bond properties of FRP were not adversely affected in any significant manner as a result of the exposure.

Journal of Composites for Construction, Vol. 17, No. 6, November/December 2013

 

Field and Survey Reports

 

Baseline Survey of Zeebak, Eshkashem and Sehghnan Districts, Badakhshan, Afghanistan,

Homam, Sayed Mukhtar (1994)

Norwegian Afghanistan Committee, Peshawar, Pakistan

 

Other Publications

 

Northern Ontario Hydroelectric Development Potential (2005)

Ministry of Energy, Ontario, Canada

Albany River Hydroelectric Potential (2005)

Ministry of Energy, Ontario, Canada