COWI and European Research Projects

COWI and European Research ProjectsDuraCreteDuraNetFITDARTSUPTUNDuring the years 1996 - 2007 the EuropeanUnion has been supporting a number ofclosely related research projects and technicalnetworks of considerable magnitude and withvery valuable and directly applicable output inrelation to safety, durability and service life designof major infrastructure concrete constructions.COWI is the only single consultant in all ofthe five interrelated projects described. Thishas placed COWI in the absolute forefront inthe rational service life design and safety assuranceof tunnel concrete structures. The aspectsof hazards are a key issue, and the mitigationof damage due to fire is in focus in thispart of the investigations. The results are generallyapplicable for all types of concretestructures exposed to an aggressive environmentand the results have been implementedin numerous recent and current constructions.

DuraCrete“Probabilistic Performance BasedDurability Design of ConcreteStructures” (1996 - 1999)(12 partners)The objective of DuraCrete is to useavailable knowledge of concrete deteriorationthrough scientificallybased modelling of the transportand deterioration mechanisms governingthe service life performanceof concrete structures. This includesa quantified classification of the aggressivityof different types of environment.Chloride induced and carbonationinduced reinforcementcorrosion have been the most advancedmechanisms in the modelling.The project resulted in the publicationof a design guide for servicelife. It adopted the probabilistic approachby introducing the uncertaintiesof the input parameters andtheir distribution functions. Theunique development is that the servicelife design approach is identicalto the well-known method of designingstructures for load, whichthen has been simplified to the socalledload-and-resistance-factor-design(LRFD) methodology. In thesame way the DuraCrete approachcan be presented in the frameworkof an LFRD procedure, just for designservice life.DuraCrete has been adopted asservice life design basis for:• The large Dutch Tunnels includingthe world record Green HeartTunnel• The Malmø City Tunnel in Sweden• The world record Sutong cablestayed bridge in China• The Sitra Causeway, Bahrain• The Busan-Geoje Fixed Link with aworld record deep immersed tunneland the bridges• The Subaya Causeway, Kuwait• The tender design of the Qatar-Bahrain Causeway• The tender proposal for the DubaiMetroCOWI was the key proposer and thescientific manager of the DuraCreteproject.Importance ofconcrete coverdesign thicknessand workmanship. DuraNet“Network for Supporting theDevelopment and Application ofPerformance-Based DurabilityDesign and Assessment ofConcrete Structures” (1998-2001)(18 partners)The recognised success of the Dura-Crete Project led the EuropeanCommission to grant support for establishinga special internationalnetwork to disseminate the valuablepossibilities of applying the Dura-Crete service life design methodologieson an international level.DuraNet organised three internationalworkshops with only invitedexperts. The participants were the18 members and a small number ofspecially invited experts handpickedin the light of the topic of eachworkshop. The titles, dates and venueof the workshops were:• WS-1: “Design of Durability ofConcrete”, which took place inJune 1999 in Berlin, Germany.• WS-2: “Service Life of RepairedConcrete Structures”, which tookplace in June 2000 in Copenhagen,Denmark.• WS-3: “Service Life Design ofConcrete Structures - From Theoryto Standardisation”, whichtook place in June 2001 inTromsø, Norway.

UPTUN“Cost-effective, Sustainable andInnovative Upgrading Methods forFire Safety in Existing Tunnels”(2002-2006) (42 partners)The safety systems in a significantpart of the existing tunnels were designedon the basis of traffic and itsestimated growth two or more decadesago. It appears, however, thattraffic has grown more significantlyand also changed in composition(more combustible and flammablegoods). Consequently, the safetylevel in existing tunnels has decreasedin cases where no intermediatemeasures were taken to copewith the changed supply of rollingstock. This holds true throughoutEurope, for road, rail and masstransittunnels.The UPTUN project main objectsare therefore:• Development of innovative technologieswhere appropriate andwhere relevant and the assessmentof existing technologies for tunnelapplication. Focus is on technologiesin the areas of detection andmonitoring, mitigating measures,influencing human response andprotection against structural damage.The main output is a set ofinnovative cost-effective technologies.• Development, demonstration andpromotion of procedures for rationalsafety level evaluation, includingdecision support modelsand knowledge transfer. The mainoutput is a risk-based evaluatingand upgrading model.COWI is member of UPTUN andresponsible for one key workingparty.

The probability that corrosion will start as afunction of the time after construction for atunnel wall or slab. Relationship shown forthree different concrete mixes.Probability of corrosion0,300,250,20Porous concreteConventional concreteDense concrete0,150,100,0500 20 40 60 80 100Time (years)of exposureDARTSD•A•R•T•S“Durable and Reliable TunnelStructures” (2001-2004)(8 partners)The objective of DARTS is to developoperational methods and supportingpractical tools for the bestpro-active decision-making processfor choosing, in each individualcase, the cost optimal tunnel typeand construction procedures.The dominating innovation ofDARTS is the integration of reliability-basedstructural design, geotechnicalissues, service life design basedon the DuraCrete methodology,hazar d design including risk assessment,environmental aspects, societalneeds, sustainability and economicaspects.DARTS is developed for the maincurrent types of tunnel constructions:rock tunnels, bored tunnels,NATM tunnels, immersed tunnels,and cut and cover tunnels.COWI was the key proposer andthe project manager and scientificmanager of the DARTS project, andCOWI was appointed co-ordinatorbetween DARTS and the networkFIT, see overleaf.Feasibility studyDecisionsConceptual designOutline designDetailed designOperation

FIT“Fire in Tunnels” a networkproject (2001-2005)(33 partners)The European thematic network onFire in Tunnels (FIT) is a group ofstakeholders focusing on the exchangeof knowledge, integrationand creation of know-how. FIT hasstrong links with actual and futureEuropean and national researchprojects.Increased traffic and the trend forlonger tunnels consequently result inhigher risks. Safety, and in particularsafety in case of fires in tunnelshave received tremendous attentionfollowing some recent serious fireincidents (Mont-Blanc, Tauern,Channel, Kaprun, Saint-Gotthard).To profit the most from theknowledge throughout Europe,from real fire accidents, testing andresearch, it is an advantage to useall available information via a Europeanthematic network.The following main objectives havebeen identified:• dissemination of RTD (ResearchTechnical Development) and designresults obtained in Europeanand national RTD projects;• to establish a set of consultabledatabases with essential knowledgeon fire in tunnels;• to realise recommendations on firedesign for tunnels;• to develop European consensusfor fire safe design on the basis ofexisting national regulation,guidelines, codes of practice andsafety requirements;• to define best practices for tunnelauthorities and fire emergencyservices on prevention and training,accident management and fireemergency operations.COWI is member and task forceleader of two tasks.

The futureThe coordinated achievements ofthese 5 projects have identified theneed for a maintained co-ordinationwithin this very essential areaof safety and performance.Therefore a new sub-group ITACommittee on Operational Safetyof Underground Facilities has beenestablished under the auspices ofthe International Tunnel Association.COWI is a key founding memberof this group.Information:Further information can be uptainedfrom the project web-pages:www.duranetwork.comwww.dartsproject.netwww.etnfit.netwww.uptun.netTorsten MølgaardHead of Department,Tunnels and UndergroundStructures+45 4597 2889tm@cowi.comSøren Degn EskesenResearch andDevelopment Manager+45 4597 2554sde@cowi.comDr. Carola EdvardsenSenior Specialist,Concrete StructuresPerformance+45 4597 2813cle@cowi.comDr. Steen RostamChief Engineer,Concrete DurabilityTechnology+45 4597 2782sro@cowi.comwww.cowi.comCOWI is a leading northern Europeanconsulting group. We providestate-of-the-art services within thefields of engineering, environmentalscience and economics with dueconsideration for the environmentand society. COWI is a leaderwithin its fields because COWI’s3300 employees are leaders withintheirs.COWI A/SParallelvej 2DK-2800 Kongens LyngbyDenmarkTel.: +45 45 97 22 11E-mail: cowi@cowi.comInternet: www.cowi.com021-1700-021e-05a