Mario Bačić

Rehabilitation Techniques for Aged Railway Tunnels

Due to fact that most of the railway tunnels in Croatia were constructed around hundred years ago, and taking in consideration lack of investments and maintenance strategies, there is an increasing need for their rehabilitation. However, this need is far greater than the available financial framework and therefore it is necessary to properly define the rehabilitation priority list and to apply the state-of-the-art rehabilitation methods to improve the safety and functionality aspects. This will result in overall lifetime increase of these critical infrastructure objects. In order to deal with such challenging task, this paper presents the techniques and methodologies for all stages of tunnel rehabilitation process, starting from investigation works in order to determine current condition of tunnel, through development of rehabilitation design, implementation of rehabilitation measures and quality control programme. The problems of non-satisfactory free tunnel profile, lining instabilities, excessive drainage of groundwater etc. will be presented through the examples of several railway tunnels in Croatia.

A Framework for Risk Management in Rockfall Protection

Rockfalls represent a constant threat to the facilities, infrastructure and inhabitants. Therefore, it is necessary to map the rockfall hazard area and to carry out the risk assessment. In the Republic of Croatia there is no systematic data acquisition of rockfalls. There is also no rockfall classification system adjusted for Croatian Karst. In this paper a Framework for Risk Management in Rockfall Protection in Croatian Karst is presented, which enables a better understanding of the problem and the cooperation of all participants in the project. Decision-making process, necessary for complex decisions, depends on the systematic study of influential factors, the adequacy and quality of information, the number of alternatives, and the use of appropriate models and techniques for selecting optimal alternative. Quantitative risk analysis is carried out if there is a possibility of estimating the probability of a certain event, based on available information about similar events that occurred in the past or on information collected in any other way and also based on personal experience. In the absence of such experience proposed framework allows a qualitative risk analysis with constant control of the consistency of subjective decision-making.

Remediation of landslides on railway line between Karlovac and Mrzlo Polje Stations

Nedugo nakon izgradnje dionice željeznicke pruge M202 Zagreb Glavni kolodvor – Rijeka (1963.), između kolodvora Karlovac i Mrzlo Polje, pojavila su se klizista koja su tijekom godina sticena razlicitim lokalnim mjerama sanacije. S obzirom na to da su se klizanja intezivirala pocetkom 2013. godine uslijed povecanih oborina, nužno je bilo brzo djelovati da se ne bi ugrozila funkcionalnost i sigurnost te dionice i građevina na platou iznad usjeka. U radu su stoga kronoloski prikazane faze sanacije klizista, pocevsi od provođenja istražnih radova, izrade projektne dokumentacije te same izvedbe.