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| Galvanized rebar lasts as long as the deck |
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Documented Field Results Of Epoxy Rebar |
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| Working Conditions- (Not Laboratory) |
HOT-DIP GALVANIZED | EPOXY COATED |
| Expected life | Good to Excellent-meets design life. | Good-field results are mixed |
| Bond strength to concrete | Excellent-meets or exceeds black rebar by 20% | Poor 30-35% less than black rebar |
| Bond strength to concrete after 20 years | Excellent | Poor-many state and world studies indicate both concrete to epoxy, and epoxy to steel seperation |
| UV resistance | Excellent-storage outside for years | 90 days |
| Resistance to normal field chloride levels | Good to Excellent-years of service even with cut ends | Lab tests are good. However, many field studies has been untaken to find a method to eliminate handling, jobsite, and concrete pouring damaged. A method has not been found to prevent chloride from attacking through the damage epxoy. |
| Can be dragged on ground | Yes | No |
| Has barrier protection | Yes | Yes |
| Metal molecule bond of coating | Yes-adherence strength is several thousands pounds/sq inch | No-adherence strength is generally several hundred pounds/sq |
| Has catholic protection (self sacrificing to prevent rust) | Yes-zinc will sacrifice to protect steel rebar from corrosion | No - chloride and water ions below coating encourage rapid expansion of corrosion |
| Simple to bend and still have catholic and/or barrier protection | Yes | No-Epoxy does not, can not provide catholic protection - impossible |
| Fabrication after coating application | Yes | Yes-must repair epoxy coat |
| Cost-initial cost at installation | Comparable | Comparable |
| Cost-full life cycle cost assessment -today's standard | Least cost choice | Most Costly |
| Lead time | 1-2 days | 2-3 weeks |
| Quantity of steel required | Equal to black rebar. | Over lap, and drops increase required steel by 5-10 % over black rebar and is an additional epoxy rebar hidden cost |
| Debonding epoxy from steel | No-bond is equal to or 20% greater than black steel rebar | Yes - Epoxy is a mechanical paint bond with measured strength of only several hundred Pounds/sq in. It is easy for chloride and water ions to pentrate under epoxy skin through holidays, patches causing corrosion and expansion |
| Debonding concrete to surface of rebar | No-bond is equal to or 20 % greater than black rebar steel worldwide | Yes-Epoxy field and lab bond strength tests are 20-35 % less as reported by worldwide studies |
| Construction damage "pokers" and "vibrators" | No | Yes-World wide studies indicate even if the jobsite is near perfect, poker and vibrator damage with occur. vibration and compaction will run 0.5% to 3.0 +% damage. |
| Delaminating during fabrication | No-Four (4) Zinc layers protect the rebar. Even if the outer Zinc Eta layer is damaged, three zinc alloy layers harder than the steel provide protection | Probable-any microscopic crack will allow chloride and water ions to atttack the steel rebar. |
| Must be touched up | Optional - good results are reported for rebar sizes of number 8 and less. World wide studies indicate very strong results if repaired per ACI standards. | Yes - extensive specs are written in an attempt to repair ends and construction damage with questionable success |
| Handling is a major problem in yard & job site | No | Yes |
| Inspection for pinholes in coating | No - rebar is imersed in Zinc bath with 100 % coverage. Inspection is simple. | Yes - constant and costly inspection for vacations, holidays and construction damage with pinholes difficult to locate |
Five Major Areas where Hot-Dip Galvanized Rebar Works:
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Paints, Powered Coatings, Epoxy For Concrete Rebar |
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Please note this file may take a little longer to load, however, it is worth the time waiting. |
| WHO SAYS GALVANIZING WORKS? | Nearly every Federal, State, County, Township, City, and Country in the world.These customers have purchased in the past and continue to purchase thousands of miles of hot-dipped galvanized guardrail, light poles, and overhead sign structures every year. In addition, hot dipped galvanized bridges with 100 year life spans are built every year.. |
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1970 THROUGH 1994
Who says galvanizing rebar works?
The following world studies
| 20562 | Coming soon - UPDATE 1980 THRU 1994 GAVANIZE RESULTS Review of 842 studies from around the world. Pubilished 1995 |
| 20673 | Coming soon 1970 to 1992 recap of current literature. |
| The use of galvanized reinforcement in building and construction () | |
| Galvanized Reinforcing Bar () | |
| Comparative Studies of Galvanized and Epoxy coated Steel reinforcment in concrete (Feb 1991) Yeomans | |
| Galvanized Rebar, the lasting method of corrosion protection (Apr 1991) University of Sheffield, UK | |
| Modern Methods of Production of Steel Reinforcement Bars and some effects on galvanizing properties. () Plowman | |
| The Galvanizing Process and coating properties (Nov 1991) Smith | |
| Galvanized Reinforcement - The BERMUDA Experience () Allan Galvanizing field experience since 1930's and complete reliance | |
| Resistance to Chlorides of Galvanized rebars (1992) Swamy | |
| Galvanized Reinforcement () Porter | |
| Corrosion of metals in concrete Yeomans | |
| Further studies of the comparative properties and behavior of Galvanized and epoxy coated steel reinforcement. (Jul 1990) Novak | |
| A comparison betwen hot-dipped galvanized and fusion bonded epoxy coatings for steel reinforcment in concrete. (Aug 1989) Yeomans | |
| This section is under development will be on line soon |
| 20662 | New York Thruway Authority exclusive endorsement of hot dip galvanized steel reinforcement rebar |
| 20673 | Stearns Bay Bridge, Michigan - Oldest Galvanized bridge in USA |
| 20674 | Bermuda Ministry of Works and Engineering says exclusive endorsement of hot dip galvanized rebar since 1950 |
| 20677 | Pennsylvania DOT study |
| 20678 | Florida DOT says - Epoxy deteriates faster than bare steel |
| 20679 | American Concrete Institute study - says significantly reduces bond strength and pull out with epoxy rebar |
| 22052 | 60-90 Years to First Maintenance after independent study of six OHIO galvanized bridges |
| 22029 | Galvanizing eliminates painting --- galvanizing costs less than $ 6 per square foot. Stark County, OH |
Additional engineering information and economic data
| 21011 | Epoxy Coating Failures |
| 22011 | What is HOT-DIPPED GALVANIZING? |
| 22014 | Are other types of GALVANIZING BETTER? NO!! |
| 22021 | GALVANIZING BENEFITS Versus STEEL |
| 22024 | FULL LIFE-CYCLE ASSESSMENT for bridges |
| 22028 | RUST COSTS AMERICA $300 BILLION A YEAR |
| 22032 | TEN BENEFITS OF HOT-DIPPED GALVANIZING |
| 22036 | 600,000 BRIDGES AND 30 % NEED ATTENTION |
| 22039 | FREQUENTLY ASKED QUESTIONS |
| 22044 | FALLACIES AND FACTS ABOUT GALVANIZING |
| 2059 | BID,QUOTE, LANGUAGE FOR BRIDGE GALVANIZING |
| 2062 | When to PAINT? |
| 2063 | How to REPAIR damaged GALVANIZED surfaces. |
| 2064 | THINKING outside the fifty-year BOX of hand-down specs. |
| 2067 | Engineering stuff thickness, standards, why it works? |
| 2069 | TELEPHONE AREA DE-CODE
BUSINESS MANAGER'S ORGANIZATIONAL TOOL |
Link to other Galvanized websites
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HIGWAY BRIDGES, MODULAR BRIDGES,I-BEAM, TRUSS. Install modular bridge in one day; drive across by sundown |
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CONVEYORS 24" TO 72" (for salt) Truss |
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DUMP TRUCKS BODIES & STAKE BEDS |
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AMERICAN GALVANIZING ASSOCIATION |
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