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Microsoft PowerPoint 5 COST534 GFRP CFRP JoGu Part1 ppt GFRP and CFRP for civil applications Ludovit Nad, University of Kosice Johann Kollegger & Johann Horvatits, TU Vienna Joost Gulikers Rijkswaters[.]
COST534, Final Workshop, Toulouse 26-27 November 2007 GFRP and CFRP for civil applications Ludovit Nad, University of Kosice Johann Kollegger & Johann Horvatits, TU Vienna Joost Gulikers Rijkswaterstaat Bouwdienst Ministry of Transport, Public Works and Water Management Utrecht, The Netherlands 1400 1200 1000 1000 847.7 Made by hand - diameter 9.15 mm 755.986 800 595.8 640.8 600 600 456.24 572.374 490 Industrial production diameter mm Industrial production diameter 15.1 mm Industrial production diameter 16 mm 400 Steel reinforcement 200 210 250 Modulus of Elasticity in GPa Values of Short Time Strength in MPa 1400 200 150 60 100 35 50 Industrial production - GFRP bars Strength: mean and characteristic (the characteristic values of yield stress are given in case of steel) Industrial production - GFRP bars Steel reinforcement M / Mu 2.1 1.9 1.8 1.7 1.6 1.5 1.4 1.3 1.2 1.1 0.9 0.8 0.7 0.6 0.5 0.4 0.3 0.2 0.1 Beam with GFRP No.1EXPERIMENT Beam with GFRP-FEM LUSAS Beam with GFRP No.2EXPERIMENT Beam with GFRP No.3EXPERIMENT Beam with Steel No.1EXPERIMENT Beam with Steel No.2EXPERIMENT Beams with Steel FEM LUSAS 10 15 20 25 30 35 40 45 50 55 Mid - span Deflection [mm] 60 65 70 75 80 COST534, Final Workshop, Toulouse 26-27 November 2007 CONCLUSIONS FOR PRACTICE •LOW MODULUS OF ELASTICITY •FLOAT IN CONCRETE •ACI 440: 20% fu •LESS SUITBALE FOR PRESTRESSING APPLICATIONS 3000 carbon HS aramid HM S-glass aramid IM carbon HM E-glass stress (N/mm2) 2000 prestressing steel 1000 reinforcing steel strain (%) • High strength/weight ratio –3 to times higher than steel –80% lighter –Fibres: 10x stronger than steel –Comparable mod of elasticity • Not sensitive to corrosion • Conductivity • High resistance against fatigue • Low axial coefficient of thermal expansion • Price –Relative expensive compared to steel –Price decreases • Brittle mode of failure • Properties dependent on type of fibre • Low compressive strength in transverse direction • Anchorage is major problem Location: Europoort, Rotterdam • Bridge type: concrete box girder • External CFRP prestressing – cables, 91 wires ∅5 mm per cable – 2650 kN prestressing per cable BBR CARBON Ext 91.φ5 O 55 BBR CARBON External 91φ5 l=75 m BBR CARBON External 91φ5 l=75 m 86.5 m 185 m 86.5 m Cable failure • Anchorage is decisive component • Time-dependent draw-in of epoxy anchorage distance of the CFRM wires measured to the front side of the anchor sleeve 94 90 89 99 100 failed GFRP 15 end plate 113 114 116 115 85 80 Anchorage after failure 60-65 mm resin removed after failure Cable failure • Anchorage is decisive component • Time-dependent draw-in of epoxy anchorage distance of the CFRM wires measured to the front side of the anchor sleeve 94 90 89 99 100 failed GFRP 15 end plate 113 114 116 115 85 80 Anchorage after failure 60-65 mm resin removed after failure New Casting Anchorage System α β Conventional conical anchorage body Segmented conical anchorage body Assembling of the conical segmented anchor geometry New anchorage system Experimental Investigations Short Term Loading Tests New anchorage for 37 CFRP-wires before and after testing Failure Load: 1900 KN Measuring rod with strain gauges 36 CFRP-wires Position of strain gauges along the measuring rod (top) and corresponding strain distribution over the anchoring length for different loading steps (bottom) First Application in Austria (1) Abutment area of the bridge Tauern-motorway bridge Golling, Province Salzburg, Austria First Application in Austria (2) Fixed end of the CFRP- wires (37 Ø mm) Anchorages before casting with the epoxy resin Casting of the anchorage with the epoxy resin Heating of the casted anchorages First Application in Austria (3) Stressing procedure CFRP-tendons below the Golling Bridge Six post-tensioned CFRPtendons in the box girder CONCLUSIONS NEW STRUCTURES AS (PARTIAL) REPLACEMENT OF STEEL PRESTRESSING EXISTING STRUCTURES FOR RESTRENGTHENING EXTERNAL APPLICATION LIMITING FACTOR: HIGH PRICE