Application. Shotcrete Training for Sprayed Concrete. Hagerbach Test Gallery Ltd. Volker Wetzig. hotcrete for Africa. 2nd to 3rd March 2009

Transcription

1 Shotcrete Training for Sprayed Concrete Application 1

2 ontent - Introduction - Production chain of sprayed concrete - Scheme for education - Experiences of training - Conclusion 2

3 Introduction Construction material of highest complexity Requirements for application Requirements for hardened concrete 3

4 Preliminary support with bolts and mesh 4

5 inal Lining with Sprayed Concrete 5

6 Introduction Construction material of highest complexity Requirements for application Requirements for hardened concrete Sprayed concrete is a construction material which is produced on site within a few seconds Introducing air for transport Adding accelerator Final distribution of concrete Covering reinforcement 6

7 Production unit of sprayed concrete 7

8 Detail of production unit (nozzle) Concrete Air Accelerator 8

9 Production chain of sprayed concrete Mix design Production and quality control of fresh concrete Application of sprayed concrete Curing of sprayed concrete and confirmation of concrete properties 9

10 tilisation for Sprayed Concrete Rock support Sealing (?) Final lining Repair / Maintenance 10

11 ix Design for Sprayed Concrete Aggregates (normally 0-8 mm) Cement Additive (Fly-ash, Silica-fume) Fibres Water Admixtures (Plasticizer, Retarder, Accelerator) 11

12 ims of Concrete Production Pump able Mix Plasticizer Processing time Retarder - Transport - Temperature Control of Concrete Production Current consumption Consistency - Flow table - Slump 12

13 Concrete production 13

14 low Table 14

15 ethods of Application Processing Dry mix shotcrete Oven-dry Earth-moist Wet-Mix-shotcrete Control of nozzle manual robotic 15

16 cheme Dry-Mix-Processing 16

17 cheme Wet-Mix-Processing 17

18 obotic Sprayed Concrete Application 18

19 arly Strength Penetration needle SIA 198 Bolting method SIA

20 Scheme for training Content Designer of tunnel Nozzle-man Tender design T - Equipment T T/D Raw materials for concrete T - Mix design T - Production process of concrete Application of sprayed concrete Application with special requirements D T/D T/D D P P 20

21 Basic for mix design: aggregates 21

22 Mix design Calculation of Mix Amount Density Volume [kg] [kg/m3] [l] Aggregates Cement Water Additives Air 10 Total

23 Flow table test Mix could not be pumped 23

24 Flow table test Mix could be pumped without any problems 24

25 ims of Sprayed Concrete Application Less rebound No back-fall Homogenous concrete Good compaction Reinforcement fully covered Early strength will be achieved Final strength will be achieved 25

26 uality of Sprayed Concrete is influenced by: Preparation of subsurface Distance nozzle-wall Angel nozzle-wall Air consumption Type and dosage of accelerator Thickness of layers 26

27 pplication of Sprayed Concrete 27

28 apacity of Concrete Application Capability of pump Movability of spraying boom Size of tunnel 28

29 Back fall of concrete! What are the reasons? 29

30 nfluence of Angel Nozzle-Wall 30

31 overing of Reinforcement 31

32 xamples of Sprayed Concrete 32

33 ersonal Protection Equipment Breathing protection Eye protection Ear protection Gloves 33

34 Certificate 34

35 Conclusion Sprayed concrete covers highest requirements on construction material Therefore sprayed concrete will be produced on site, skilled workers are inalienable Steering parameters have to be used in an adequate way 35

36 Good Luck! Thank you for your attention! 36