Orientering fra prosjektet Tyngre bruvedlikehold

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1 Bedriftsklyngesamling Svolvær, februar 2017 Orientering fra prosjektet Tyngre bruvedlikehold Roy Antonsen

2 Prosjektet Et gjennomføringsprosjekt opprettet for å øke intensitet og gjennomføringsevne på rehabiliteringsprosjekter på bruer i Nord-Norge. Region Nord har ca. 500 bruer over 20 m (Riks- og fylkesveg) Spesialinspeksjoner (planlegging, gjennomføring og dokumentasjon) Planlegging og utførelse av rehabiliteringer Oppfølging 3 ansatte pr feb Prosjektleder, byggeleder og kontrollingeniør

3 Bruer (foreløpig) i prosjektet Rehabiliteringer: Tiltak Status Storvalen Katodisk beskyttelse, etc Ferdigstilles høsten 2016 Breisundet Katodisk beskyttelse, etc Ferdigstilles høsten 2016 Gimsøystraumen Katodisk beskyttelse Prosjektering/beskrivelser pågår Kjerringstraumen Overflatebehandling overbygning Beskrivelser pågår Tjeldsundbrua En rekke tiltak.. Beskrivelser pågår Kvalsundbrua Overflatebehandling, KB Ikke oppstartet Hoholmen Spesialinspeksjon planlagt 2016 Kanstadstraumen bru Spesialinspeksjon planlagt 2016 Oppfølging av KB-anlegg: Sørstraumen bru, Kvænangen Sortlandsbrua Skattørsund bru Bes tilling Inspeksjon KB-anlegg, overlevering etter 10 år Inspeksjon og justering av KBanlegg Inspeksjon av KB-anlegg. Reparasjon av gammelt anlegg eller installasjon av nytt? Status Noen feil registrert, reklamasjon? Anlegg fungerer godt, justering foretatt. Reparasjon av KB-anlegg under vann Ikke påbegynt

4 Armeringskorrosjon, prinsipper

5 Korrosjon NaCl O2 Betong Passiv film Armering

6 Titan-nett Strømkilde Betong Armering

7 Breisundet and Storvalen. 240 m long box girder bridges

8 Reinforcement corrosion, delaminations

9 What do we do When installing CP? Chisel away damaged concrete by water jetting

10 Results after water jetting

11 Results after water jetting (2)

12 Replace damaged reinforcement

13 Rubbing of concrete surface by water jetting Før Etter

14 Install CP and instrumentation

15 Install titanium mesh anodes

16 Shot-creeting (spraying) all surfaces by CP mortar. Titanium mesh completely sheated by CPmortar

17 What we are trying to improve Plan Do Check Act (PDCA) Is an iterative four-step management method used for the control and continual improvement of processes and products Continous improvements (LEAN)

18 Continuous improvement

19 So, what did we do so far? Sortlandsbrua, 25 year old CP system We have checked all CP data. Current and voltage values are fine. Detailed condition survey not yet done

20 Sørstraumen bridge, CP installed in

21 Titanium strip anodes installed with about 30 cm spacing between

22 Titanium strip anode, 24 mm wide

23 Sørstraumen bridge. Delaminations. Main inspections showed delminations in Veivesenet (region nord) mapped the delaminations in 2007, 2013 and in Showed that the delaminations were growing in clusters. Purpose of the 2016 inspection was to reveal the root cause of the delaminations. (Tender documents were based on functional requirements. No specific claim to materials or procedures). Remember: this is only a discussion about materials and methods. Not about contractors. Therefore no contractors are mentioned in this presentation, only potential improvement areas

24 CP Sørstraumen. Conclusions Main part of the CP system is ok. Polarisation satisfactory polarisation and good reference electrode readings. Two faults/defects were observed: 1. Delaminations between spray mortar and bridge concrete 2. Delaminations and cracking due to acidification around titanium strip anodes

25 Delamination between sprayed mortar and bridge concrete. Sandblasting was allowed

26 Acidification around anode

27 Cover depth of anode measured to only 3mm.

28 Visual mangnitude of the acidification

29 Vassås bru CP installed in Waterjetting, CP mortar, titanium mesh anodes.. Everything should be ok.but

30 Vassås bridge, delaminations Detailed inspection will be done in summer

31 Going back to Storvalen and Breisund bridge Extra man-hours have been used for quality control especially regarding delaminations, continuity of reinforcement and short circuit (A-K). The contractor is renown for beeing good at mortar spraying and shotcrete, but we revealed about 5 to 6 delamination areas. One big, more than 3 m high

32 Any problems with our traditional metods? Dust maybe? Falling concrete debris?

33 Dust development, spraying mortar

34 Conductive paint systems. Gimsøystraumen, CP, FoU-field. Underside of box girder, 15 m long

35 Gimsøystraumen FoU, CP, conductive paint.

36 Tjeldsund bridge (suspension bridge).

37 Other challenges. CP on suspension bridges

38 Concrete plate i main- and side-span. Trussess prevent water jetting and mortar spraying.

39 Dust for chloride samples were collected. Analysis showed close to 1% Cl (by cement weight).

40 Corrosion on steel bolts, dowel from top chord

41 Another example

42 Svinøy bridge Municipal bridge in Svolvær. To be protected by CP conductive paint. Work on test field have started. Public road administration, region nord will attend as observers

43 Andre utfordringer for Tjeldsundbrua. Alkalireaksjoner runde pilarer under viadukter Frostnedbrytning Utluting

44 Omfattende lokal opprissing med utfellinger samt ekspansjon.

45 Oppgradering til Bk10-60, samt vindforsterkning

46 Måløy bridge About to be one of the biggest CP-projects in Norway. Estimated surface is m 2 The project is now in design phase tender documents