management of tunnels on the zagreb – macelj motorway ... - Index of

84Operation <strong>of</strong> a tunnel requires, first and foremost, asystematic approach to undisturbed and safe traffic flowthrough the <strong>tunnels</strong>, which makes it necessary to optimizeall the parameters <strong>of</strong> the tunnel as a whole, rangingfrom tunnel equipment systems, through maintenance andmonitoring <strong>of</strong> tunnel structure, to the readiness to act incase <strong>of</strong> undesirable events.In case <strong>of</strong> the traffic safety, operation <strong>of</strong> <strong>tunnels</strong> includefollowing basic factors: tunnel infrastructure (passivesafety measures), tunnel Operator (active safetymeasures), tunnel users, tunnel traffic structure and trafficvolume. Tunnel infrastructure or passive safety measuresmean tunnel structural features as well as tunnel equipmentsystems features. Tunnel structural features understandsnumber <strong>of</strong> tunnel tubes, geometry <strong>of</strong> tunnel, liningtype, escape gallery, cross passages numbers, drainagetypes, rock mass characteristics, excavation method andsupport type etc. Tunnel equipment systems features includesinstalled equipment systems such as: tunnel lighting;tunnel ventilation and CO, wind speed and visibilitydevices; fire detection system; traffic <strong>management</strong> system;tunnel SOS phones; public address loudspeaker; radio diffusionsystem; CCTV (AID based) control and supervisionsystem (SCADA); tunnel UPS devices; water supplyand hydrant network system etc. The function <strong>of</strong> installedequipment is to improve road safety, while ensuring timelyand high-quality information for users and employeesregarding the conditions on the motorway. Active safetymeasures represent operator’s procedures, implementation<strong>of</strong> this procedures, cooperation and communicationwith emergency services, and maintenance <strong>of</strong> tunnel infrastructure.Operator’s procedures consisted standard operatingprocedures and emergency procedures. Standardoperating procedures are used for coordination, analysesand passing on the information gathered from the varioustunnel equipment systems helping the Operator to makethe right decisions in operational process.In standard operating procedures are defined activitiesneeded to be performed when operator is reporting malfunctionand rectification <strong>of</strong> equipment. In order to ensurenormal and reliable operability <strong>of</strong> all tunnel systemswith minimum disturbance <strong>of</strong> the traffic, to protect dataintegrity and to reduce non availability <strong>of</strong> the equipmentto minimum. As component (Pili, 2008) to Standard operatingprocedure with defect report and maintenance responseis Disaster Recovery procedure ensuring businesscontingency <strong>of</strong> Zagreb – Macelj motorway.Emergency procedures are used for emergency casessuch as the accidents or undesirable events that representa serious interruption <strong>of</strong> traffic safety. Such cases requirequick implementation <strong>of</strong> temporary measures or usage<strong>of</strong> resources until the end <strong>of</strong> the accident or interruption.In accordance with the bylaw, the Operator has the dutyto organize fire fighting duty, and fire fighting drills haveto be conducted in order to ensure the readiness <strong>of</strong> staffmembers and the functionality <strong>of</strong> the system in case <strong>of</strong>possible unwanted events. In the course <strong>of</strong> one year, fiveRud.-geol.-naft. zb., Vol. 25, 2012.Z. Deković, I. Pili: Management <strong>of</strong> <strong>tunnels</strong>...“dry” drills are conducted (which includes checking thereadiness to start the intervention at the required speed,under full fire fighting equipment), as well as one “wet”drill (where the simulation includes unwanted events, togetherwith the consequences <strong>of</strong> fire). Wet drills are conductedin the longest <strong>tunnels</strong>, Sv. Tri Kralja tunnel and/or Brezovica tunnel, both <strong>of</strong> which are <strong>tunnels</strong> with twowaytraffic. Each year, a different script <strong>of</strong> an accidentis prepared, and all the relevant services (Service 112;the police; emergency health service; public fire fightingunit; etc.) are included in the wet drill. Furthermore,when it comes to <strong>tunnels</strong> with two-way traffic, there is anincreased level <strong>of</strong> maintenance <strong>of</strong> systems directly connectedwith fire protection, which is logical given the flow<strong>of</strong> activities aimed at the prevention <strong>of</strong> unwanted events.The Operator is tackling the <strong>tunnels</strong> with two-way trafficwith even more attention than usual, precisely because <strong>of</strong>the increased risk <strong>of</strong> unwanted events taking place.Maintenance <strong>of</strong> tunnel infrastructure represents one <strong>of</strong>the operational tools in <strong>tunnels</strong> operation. It is carried outin accordance maintenance manual, requirements, bylawthat is included and amplified in operation and maintenanceprocedures.Tunnel maintenance works can be divided into maintenanceworks on a tunnel as a structure on the one hand,and, on the other hand, there are the maintenance workson the tunnel equipment system. Maintenance works on<strong>tunnels</strong> as structures include the following: tunnel inspection;tunnel cleaning; and construction maintenance <strong>of</strong>the tunnel. Tunnel inspections can be periodical (e.g. seasonalinspections and yearly inspections), and there arealso general tunnel inspections, as well as extraordinaryinspections. Periodical inspections include the visual inspection<strong>of</strong> the tunnel. Seasonal inspections are performedafter the winter and summer periods (prior to and afterthe tourist season), and they are undertaken in order toevaluate traffic safety and effectiveness <strong>of</strong> tunnel equipment,with the aim <strong>of</strong> recognizing certain characteristicsthat might point to damage. Annual inspection is conductedat least once every two years, in order to estimatethe tunnel condition, and to evaluate possible damage thattunnel elements might be exposed to. There is also theneed to evaluate safety and usability <strong>of</strong> the tunnel in thecoming period, until the next annual inspection. Generalinspection (Mlinarević, 2007) <strong>of</strong> tunnel as a structure isconducted at least once every six years. It includes a detailedinspection <strong>of</strong> the tunnel as structure, which is a taskperformed by the trained staff members <strong>of</strong> the Operator,together with a specialized external expert company. Tunnelinspections provide insight into possible damage andshortcomings <strong>of</strong> a tunnel, in terms <strong>of</strong> its structure stability,traffic safety, and the durability <strong>of</strong> tunnel structure.When it comes to tunnel cleaning, it includes cleaning<strong>of</strong> all the elements <strong>of</strong> the tunnel drainage system; cleaning<strong>of</strong> tunnel walls and tunnel equipment, accompaniedby tunnel washing. The cleaning <strong>of</strong> the tunnel drainagesystem is conducted periodically, with prior inspections