SAN DIEGO PLASTICS - Resolite FRP PANEL DESIGN CONSIDERATIONS2220 McKinley AvenueNational City CA 91950800/925-4855 619/477-4855 FAX 619/477-4874FRP ROOFING & SIDING PANELSFRP PANEL DESIGNCONSIDERATIONSResoliteFRP panels are designed to meet a wide spectrum of structural andaesthetic considerations. While heavier glass reinforcement permitsstronger panels with greater span capabilities, light transmission andaesthetic appearance will be affected in translucent panels.Conversely, FRP panels incorporating onlychopped strand glass provide excellent clarity and durability but do nothave the longer spanning capability achieved with multiple glasscompositions.With over 50 years as the leader insupplying superior solutions to the industrial construction andcorrosion resistant markets, Resolite realizes the need to havealternatives in FRP panel design. Therefore, Resolite offers a varietyof resin/glass reinforcement product compositions to meet virtually anyrequirements.Resolite Tred-Safe, type 1645,utilizes a five layer combination of reinforcement including C/WBarriers, bidirectional continuous strand woven and chopped strandglass. Tred-Safe is Resolite's toughest roofing or siding panel with anominal weight of 16 oz./sq.ft. And approximately 45% glassreinforcement.This heavy combination offiberglass reinforcement coupled with Resolite's resilient resinprovides a panel that is strong, flexible, and truly walkable.Resolite'shigh strength '40' Series panels are available in fire-rated CRFS25Aopaque and FS25A translucent systems and in many types - 1440 thru 840.These panels incorporate approximately 40% glass reinforcement and havenominal weights of 14 oz. Per square foot respectively. '40'Series panels utilize a combination of glass reinforcement includingbidirectional continuous strand woven and chopped strand glass providingan excellent blend of strength and resiliency.Resolite's'30' Series panels are available in CRFS25A opaque and FS25A translucentsystems and in many types - 1430 thru 830.
These panels incorporateapproximately 30% glass reinforcement and have nominal weights of 14 oz.thru 8 oz. Per square foot respectively. '30' Series panels utilizeResolite's traditional chopped strand glass reinforcement providing aresilient panel with a long history of good performance. They alsoprovide the best clarity in a translucent panel. In addition, '30'Series panels are available in non-fire retardant Acryloy translucentand CR-Acryloy opaque systems.All Resolite products areconstructed with a matrix of thermoset polymer resin and fiberglassreinforcement forming a fiberglass reinforced polymer composite panel.The resin system surrounds the glass fiber and under heat and pressure achemical reaction locks the material into a composite unit. In thefinished panel, the resin provides fire resistance, weatherability, andcorrosion resistance as well as color and aesthetic properties. Thefiberglass reinforcement provides impact resistance, strength andstability which are the qualities that determine the structuralcapabilities of the panel.AnFRP panel's ability to absorb forces without damage to its structuralintegrity is critical to long term performance.
In order to achievedesired characteristics, Resolite has studied various combinations offiberglass reinforcements. Straight continuous glass provides stifferand longer spanning panels which are susceptible to fracturing along thelinear glass under continuous cycling and especially foot traffic.Chopped strand glass reinforced panels span less but provide moreresiliency. Over 50 years of field performance have proven that thisflexibility allows Resolite '30' Series FRP panels to perform over thelong term.When higher strength, longerspanning panels are required, a combination of glass reinforcementincluding bidirectional continuous strand woven and chopped strand glassis the ideal solution. The bidirectional continuous strand woven glassreinforcement provides added strength for longer spans.In addition, the woven patterncombined with the chopped strand more evenly distributes stress fromcyclic and impact loadings thus allowing an FRP panel to maintain itsresiliency. This combination provides excellent performancecharacteristics in all Resolite '40' Series FRP panels. And, inTred-Safe, a multi layered woven construction allows walkability inopaque or translucent roof panels.All Resolite panels aredesigned in accordance with the L/D limits specified in ASTM D 3841.This standard recognizes the performance capabilites of flexiblefiberglass reinforced polyester polymer panels.
The natural resiliencyof FRP panels accommodates large deflections due to temporary windloads. When the load is removed, the panels return to their originalposition with no fastener hole elongation taking place. This phenomenonhas been verified by extensive full scale testing and Resolite's over 50years of field performance.Since FRP is a compositematerial, a number of tests are performed in order to determine theperformance characteristics of Resolite panels.
Tred-Safe Deck is the smart choice for highly corrosive environments associated with flat, built-up type roof systems. A high strength, light weight roofing assembly, Tred-Safe Deck is an ideal replacement for old wood decks, spalling concrete channel slabs or other corroded systems.
The published physicalproperties are determined from small scale coupon testing. However,these properties can not be simply extrapolated into Load/Span Tablesdue to the composite nature of FRP.
Therefore, Resolite performs fullscale tests by the vacuum box method, ASTM E 72, in order to simulateactual field conditions.Resolite Load/Span Tables arebased on the results of the described full-scale tests. The allowablespan is limited by panel stress, fastener pullover and deflectionlimitations.
The results are further limited by factors of safety. AllResolite wall and roof panel Load/Span Tables incorporate a factor ofsafety of 1.88 for wind loads and 2.5 for live loads.ResoliteLoad/Span Tables do not consider the effects of elevated temperature orcorrosive environments. Over the long term, some reduction in propertiesis possible and should be factored into the selection of allowablespans, especially when safety is a consideration.FRP IS NOT STEELFRP panels do not perform the sameas steel panels and therefore should not be designed to the samerequirements. Steel panels are generally 20 times stiffer thanan equivalent FRP panel of the same profile. Since steel panelsare commonly designed to deflection limits as restrictive asL/360, a proportional deflection for FRP panels would be L/18 orless. Coincidentally, this deflection limitation is in line withthe widely recognized and accepted deflection criteria specifiedin ASTM D 3841, 'Standard Specification for Glass-fiberReinforced Polyester Plastic Panels'.
This deflection limit isL/20 for wall panel and L/40 for roof panel applications.Resolite's over 50 years of experience in the production of FRPpanels, combined with actual on the job performance, validatesthe ASTM D 3841 deflection limits for these naturally resilientpanels.Return to.