Tests der Wirkung von PCE-Fließmitteln auf Stoffe für Ressourcen-effizienten, nachhaltigen Beton

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1 Tests der Wirkung von PCE-Fließmitteln auf Stoffe für Ressourcen-effizienten, nachhaltigen Beton Effect of PCE-Superplasticizers on Powders for Eco-Concrete Institute of Technology and Testing of Building Materials Graz University of Technology Institute of Applied Geosciences Laboratory for Particle Analysis (RCPE) Dr. J. Juhart Rheo-Kolloquium Regensburg 1

2 Motivation Climate Protection and Sustainable Development N 2 O CH 4 CO 2 Quelle: IPCC: Climate Change 2007: Synthesis Report Cement production causes ~ 5% of world wide CO 2 -emission [Quelle: VÖZ] Concrete demand worldwide ~ 7 billion m³/year [KIT 2012] Dr. J. Juhart Rheo-Kolloquium Regensburg 2

3 Development of Eco-concrete 133% 100% 67% 33% 0% strength (fcm,28d) open porosity GWP PEI reduction of GWP and PEI by % is possible equal concrete performance Dr. J. Juhart Rheo-Kolloquium Regensburg 3

4 Packing Optimization & Effect of Fillers cement micro filler eco-filler interstitial water water layer normal paste + + superplasticizer water layer thickness + filled eco-filler voids CEM-clinker w/b-ratio (w/c ) eco - e.g. HSC concrete Same workability/strength/ durability of eco-concrete and normal concrete Dr. J. Juhart Rheo-Kolloquium Regensburg 4

5 Flowability of Different Powders Which SP do you recommend for eco-concrete and what performance will we reach with different fine powders? Spread flow test Dr. J. Juhart Rheo-Kolloquium Regensburg 5

6 Superplasticizers PCE superplasticizer [PCE] application SP 55 ready mixed concrete SP 108 ready mixed concrete SP 109 precast concrete SP 110 precast concrete SP 144 precast concrete SP 147 precast concrete SP 170 precast concrete SP 182 precast concrete bulk density PCE content (solid) g/cm³ M.% 1, , , , , , , ,07 30 CEM Ø ca. 10 µm PCE ca. 10 nm Quelle: SIKA Produktbroschüre Dr. J. Juhart Rheo-Kolloquium Regensburg 6

7 Powders Portland Cement d 50 = 7,5 µm Micro-fillers d 50 < 4 µm Eco-fillers 5 µm < d 50 < 15µm inert stone powders type true density ρ 0 grain size d 50 location parameter x slope n Blainevalue water demand (MEM) V ws /V p sensitivity to addition of water Ep g/cm³ µm µm cm²/g kgco 2 /t MJ/t cem I 52,5 R 3,14 7,50 8,50 0, ,92 0, quartz eco 2,65 13,80 18,60 1, ,85 0, quartz micro 2,65 3,26 4,60 1,10 (12680) 0,83 0, microsilica 2,20 0,20 (34908) 1,28 0,0033 (0) (0) limestone micro 2,73 2,20 3,50 1, ,61 0, limestone eco 1 2,70 9,00 15,80 1, ,59 0, limestone eco 2 2,70 12,00 20,40 1, ,69 0, dolomite micro 2,90 3,30 4,30 1, ,85 0, dolomite eco 2,86 15,00 33,50 0, ,61 0, GWP PEI factor 1/20 Dr. J. Juhart Rheo-Kolloquium Regensburg 7

8 Water Demand and Flowability of Powders New combination-method MEM-ST Mixing energy method (MEM) water demand at saturation (Vws/Vp) void content Spread flow test ST (Okamura) water demand for certain spread flows (Vwf,i/Vp) cement micro-filler (limestone) eco-filler (quartz) V wf /V p Ep,cem MEM minimum water demand V ws /V p E p,quartz Ep, EEp, limest. p,limestone no flow spread flow [mm] Water demand for certain spread flow Dr. J. Juhart Rheo-Kolloquium Regensburg 9

9 Sequence of Testing of Water-Powder mixes with SP water/powder mixes at minimum water demand (MEM) constant starting consistency addition of superplasticizers / mixing spread flow tests rheometer test SP dosage m PCE _ solid V powder m PCE _ s V p Dr. J. Juhart Rheo-Kolloquium Regensburg 10

10 Results cem I 52,5 R; d 50 =7,5µm 400 spread flow [mm] SP 144 etc. HC 150 SP 108 LC 100 0,00% 0,25% 0,50% 0,75% 1,00% 1,25% 1,50% m PCEsolid /V P [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 11

11 Results cem I 52,5 R; d 50 =7,5µm 400 spread flow [mm] SP 144 etc. HC 150 SP 108 LC 100 0,00% 0,25% 0,50% 0,75% 1,00% 1,25% 1,50% m PCEsolid /V P [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 12

12 Results cem I 52,5 R; d 50 =7,5µm limestone eco 1; d 50 =9,0µm limestone eco 2; d 50 =12,0µm spread flow [mm] SP 144 etc. HC 150 SP 108 LC 100 0,00% 0,25% 0,50% 0,75% 1,00% 1,25% 1,50% m PCEsolid /V P [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 13

13 Results 500 spread flow [mm] SP 144 etc. HC cem I 52,5 R; d 50 =7,5µm quartz eco; d 50 =13,8µm limestone eco 1; d 50 =9,0µm limestone eco 2; d 50 =12,0µm 150 SP 108 LC 100 0,00% 0,25% 0,50% 0,75% 1,00% 1,25% 1,50% m PCEsolid /V P [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 14

14 Results 500 spread flow [mm] SP 144 etc. HC cem I 52,5 R; d 50 =7,5µm dolomite micro; d 50 =3,3µm dolomite eco; d 50 =15µm quartz eco; d 50 =13,8µm limestone eco 1; d 50 =9,0µm limestone eco 2; d 50 =12,0µm 150 SP 108 LC 100 0,00% 0,25% 0,50% 0,75% 1,00% 1,25% 1,50% m PCEsolid /V P [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 15

15 Results 500 spread flow [mm] SP 144 etc. HC cem I 52,5 R; d 50 =7,5µm dolomite micro; d 50 =3,3µm dolomite eco; d 50 =15µm quartz eco; d 50 =13,8µm limestone micro; d 50 =2,2µm limestone eco 1; d 50 =9,0µm limestone eco 2; d 50 =12,0µm 150 SP 108 LC 100 0,00% 0,25% 0,50% 0,75% 1,00% 1,25% 1,50% m PCEsolid /V P [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 16

16 Results 500 spread flow [mm] quartz limestone SP 144 etc. HC cement cem I 52,5 R; d 50 =7,5µm dolomite micro; d 50 =3,3µm dolomite eco; d 50 =15µm quartz eco; d 50 =13,8µm limestone micro; d 50 =2,2µm limestone eco 1; d 50 =9,0µm limestone eco 2; d 50 =12,0µm 150 SP 108 LC 100 0,00% 0,25% 0,50% 0,75% 1,00% 1,25% 1,50% m PCEsolid /V P [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 17

17 Rheometer Tests water/powder mixes with constant starting consistency (near minimum water demand, spread flow= 130 mm) addition of superplasticizers + external pre-mixing assumption: linear Bingham flow-curve torque [mnm] rel. yield value M0 rel. viscosity η rotational frequency [1/min] V measuring ~ 15 ml Dr. J. Juhart Rheo-Kolloquium Regensburg 19

18 Specifications Rheometer Measurements rotational frequency [1/min] test profile (rate of shear history) pre shearing data aquisition measurement points testing time [sec] Dr. J. Juhart Rheo-Kolloquium Regensburg 20

19 Results Rheometer flow curves torque [mnm] CEM I 52,5 R min. water demand SP_144 0,025% SP_144 0,4% M 0 yield value at min. water demand viscosity SP saturation torque [mnm] dolomite powder "eco" min. water demand SP_144 0,025% SP_144 0,15% M 0 yield val. at min. water demand viscosity SP saturation rotational frequency [1/min] rotational frequency [1/min] Yield value min. water demand M 0,mwd ~ const. for all water/powder mixes rel. M 0 M M 0 0, mwd Dr. J. Juhart Rheo-Kolloquium Regensburg 21

20 Results Rheometer yield stress (rel. M 0 ) vs. SP-dosage rel. M0 [ ] rel. M0 [ ] 1,2 1,0 0,8 0,6 0,4 0,2 SP 144 HC 0,0 0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 1,2 1,0 0,8 0,6 0,4 0,2 mpce_solid/vp [%] SP 108 LC CEM I 52,5 R limestone eco 1 dolomite eco dolomite micro limestone micro quartz eco microsilica 0,0 0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 mpce_solid/vp [%] CEM I 52,5 R limestone eco 1 dolomite micro dolomite eco limestone micro quartz eco microsilica Dr. J. Juhart Rheo-Kolloquium Regensburg 22

21 Results Rheometer rel. M 0 vs. rel. η 1,2 SP 108 LC rel. M0 [ ] 1,0 0,8 0,6 0,4 0,2 CEM I 52,5 R limestone eco 1 dolomite micro dolomite eco 0,0 0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 mpce_solid/vp [%] rel. η [ ] 1,2 1,0 0,8 0,6 0,4 0,2 SP 108 LC CEM I 52,5 R limestone eco 1 dolomite micro dolomite eco 0,0 0,00 0,25 0,50 0,75 1,00 1,25 1,50 1,75 mpce_solid/vp [%] Dr. J. Juhart Rheo-Kolloquium Regensburg 23

22 Influence of PCE-SP on Microsilica (d 50 ~0,2µm) torque [mnm] microsilica rotational frequency [1/min] SP_108 LC 0,05% SP_144 HC 0,05% min. water demand + SP Dr. J. Juhart Rheo-Kolloquium Regensburg 24

23 Summary and Conclusion investigations by spread flow test and Rheometer SP-demand of CEM I > SP-demand of most stone powders with similar fineness to CEM I (differs for quartz-dolomite-limestone) viscosity of CEM I mixes > viscosity of most stone powder mixes of similar fineness SP-demand with increasing fineness of powders increase of yield stress & agglomeration of PCE with very fine powders observed for stone-powders: only small differences between SP-HC and SP-LC spread flow over time: decrease for cement (SP-HC ) > decrease for stone powders (almost no decrease over time for stone powders with all SP) estimation of spread flow of powder-mixes is possible when knowing the SPdemand of single ingredients (by summing up the weighted spread flows) Outlook: testing of the effect of SP on powders in pore solution of cement-limes is recommended (pre-tests show a big influence of ph-value and ions in pore solution on the interaction of powders and pore solution) Dr. J. Juhart Rheo-Kolloquium Regensburg 25

24 Thank you for your attention! Co-authors: Claudia Nickel, Prof. J. Tritthart Data based on student works of D. Borovina, A. Schönauer, C. Maier, TU Graz 2014/2015 Dr. J. Juhart Rheo-Kolloquium Regensburg 26