Durability for Carbon Fiber Reinforced Polymers on Timber StructuresJason Bercot

What are the objectivesIdentify the key parameters affecting bond characteristics between CFRP-Timber systemsIdentify a quality anchorage system for CFRP-Timber strengtheningExamine the effects of environmental conditions on the durability of the systemsDevelop a new theory, based on the findings from the above topics for strengthening timber structures by smart CFRP retrofitting

BackgroundTimber is a remarkable building material, it is a renewable material, and it is a biodegradable material. Ageing timber structures need to be looked after, repaired, upgraded, or torn down if neglected.This causes economic and social loss due to the cost and inconvenience of replacing structures.

What effects are there Economic Timber energy cost is 2,300% less than that of steel on the global scale CFRP is stronger by weight than steel, saving materialSocialSafety of Heritage structuresTemporary inconvenience during retrofittingTimber-CFRP systems are versatile & easy to retrofit

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At presentAustralia, 8 story timber framed structures now permittedUSA, 12 story timber framed structuresSweden, 34 story timber framed structureUsed to be only 3 story

Higher structures means increased loadingBonding CFRP to timber beams means less timber is needed

How should we pursue thisTest Program AMoistureTemperatureUltra-violet ExposureChemicalHumidity

How should we peruse this

Test Program BAnchoringSDMADMA

Testing species

Chosen for their Bush Fire Rating, Size Availability, Frequency of use in construction, & Strength

Testing specimensCFRP Sheets on Square Timber BeamCFRP Plates on Square Timber Beam with Lap Joint

Moisture with temperature variations

Range of Temperature

UV Exposure for varying time framesNumber of SpecimensTreatmentExposureDuration511295 365 nm6 months512295 365 nm12 months513295 365 nm18 months

Chemical solutionsNumber of SpecimensTreatmentDurationSolution514744, 4380, 8760 hrsH2O515744, 4380, 8760 hrs3.5% NaCl & H2O516744, 4380, 8760 hrsCaCo3 & H2O

Humidity with Temperature

Anchoring

Sandwich Discontinuous Mechanical Anchorage Discontinuous Mechanical Anchorage

TestingFailure TestingShearBending

Observing Debonding of CFRP timber interface

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Impact & outcomeBenefit on a national level

Increase world data on CFRP-retrofitting

Increased behavioural knowledgeLow cost

Non-Invasive procedure

Beneficial for steel & concrete

ConclusionBy looking into commonly used Australian timber, as well as experimentation under what would be standard operational settings for any timber structure that has been or would be built in the future.

Completion of this research will help identify the key parameters affecting bond characteristics between CFRP-Timber Systems, identify a good quality anchorage system for timber-CFRP strengthening system, examine the effects of environmental conditions on the durability of the system, and develop a new theory, based on above findings for strengthening of timber structure by smart CFRP retrofitting.