Choice of Grout Curtain type of dam “Rečani” on Orizarska river – Kočani

In the frames of Preliminary design for choice of dam type for dam “Rečani” on river of Orizarska near Kočani, three types of embankment dams were elaborated. Based on the results from geological, hydrogeological, geotechnical investigations and recommendations of the geotechnical model, possible alternatives of the grout gallery and curtain were designed. Structural and geotechnical analyses were performed for each of the solutions. At the end, total costs of dam construction and grout works were calculated. Comparing all important factors, optimal design of the grout curtain was proposed. The selection of the optimal type of embankment dam and grouting curtain was also done with application of multi-criteria optimization, by applying of the method of compromise programming

Model for GIS landslide database establishment and operation in Republic of Macedonia

Landslides are one of the most damaging and most significant geo-hazards in the Republic ofMacedonia. Due to many reasons landslide data collection in the past have been generally unsystematic. Knowingthat new occurrences are to be expected in future, brief overview on landslide databases in Europe is given and modelfor establishing and operation of national GIS landslide database is proposed in the paper. Model for assignment ofgovernmental body on landslides, along with structure and way of operation of the envisaged database is presented.Formation of this landslide database is the basic step towards better understanding of the landslide hazard in future.This database will enable conditions for selection of most endangered regions and selection of appropriate models forlandslide hazard and risk zonation. As a result, land use planning will become more efficient, and vulnerability ofpeople and goods will be decreased. In this context, some results from recent landslide susceptibility assessment studiesare also presented

ASSESMENT OF ROCKFALL DITCH EFFECTIVENES BY APPLICATION OF COMPUTER SIMULATIONS, AN PROBABILISTIC APPROACH

Different types of geohazards frequently affect road and railway traffic. Among them, in the case of mountainous terrains, the rockfalls are considered to be most usual. They cause economic losses of different magni-tude, in some cases even loss of human life. In order to improve the management of the rockfall hazard and risk, researchers had been developing many different methodologies for assesment and design of effective control, protection and preparedness measures. One of the approaches is to apply a structural measure along the road/railway line in the form of a rockfall catch ditch at the toe of the rock cuts. Experimental field tests and computer simulations by many authors have investigated the effectiveness of these ditches, with main goal being to design ditches that are as effective as possible. The paper presents application of computer simulation technique coupled with probabilistic analysis. The main idea is to test the effectiveness of rockfall catch ditches with different geometries, by simulating rockfall blocks of different geometrical shapes. Beside variation of the ditch and block geometry, also varied are the height and slope angle of the rock cut. Results from the probabilistic simulations show the different degree of ditch effectiveness in the investigated cases. The approach is considered useful for the goals in the design process, with main benefits being the improved management of the rockfall risk and economical rationalization of cuts design

Preparation of GIS landslide inventory for the Polog Region

This paper deals with preparation of Geographic Information Systems (GIS) landslide inventoryfor the Polog region. A number of activities were undertaken for this purpose, such as: analysis of own data on landslides, visits of the sites noted in the surveys filled by municipalities, digitizing of landslides from old geological mapsin scale 1:25000, analysis and digitizing of landslides from the archive of the Geological Survey of Macedonia, interviews with employees and retired colleagues from geotechnical companies, analysis of landslides along the channelsof the “Mavrovo” system, visit to the National University in Tetovo and joint site visit, and visits to several geotechnicalcompanies in Macedonia. Since this is the first attempt to create a regional landslide inventory in N. Macedonia, theadopted structure of the inventory is presented in the paper. Moreover, to see what benefits can be gained from theavailability of such inventory some of the most important findings regarding the landslides are presented further. Currently the inventory consists of 136 occurrences, and in time it should be appropriately updated. The main findingsrelated to the distribution and characteristics of the landslides show that future analyses should include preparation oflandslide susceptibility/hazard models both for shallow and deep landslides, as well as for flow-like type of slides. Inthe following stages of investigation, it is planned to analyze a LIDAR (LIght Detection and Ranging) survey that isbeing prepared for the region and incorporate more landslides in the inventory. Also, findings of the InSAR (Interferometric Synthetic Aperture Radar) analysis will be combined with the inventory, which will lead to conclusions on themovement rates of detected sites. The latter two approaches will be presented in future papers

Range of Engineering-Geological properties for some Carbonate Rock complexes from Balkan Peninsula

The Carbonate Rock masses are a geological media with extremely complex states and properties, which has a certain influences on the mechanical and hydraulic behavior during construction and exploitation of engineering structures. Practical aspects of the problem analysis arise from the fact that the areas of Bosnia and Herzegovina, Macedonia and the entire Balkans is characterized by presence of wide areas covered with carbonate complexes, where large number of complex engineering structures have been, or shall be constructed in the future. In this context, their engineering-geological modeling is still a practical and scientific challenge. The analysis of engineering- geological properties is one of the main steps in forming of analytical and geotechnical models for complex rock structures. This article gives a data about the range for these properties, according to the results from an extensive investigation program. Some original correlations and testing results are given and they are compared with some published relations from the world

Rockfall Hazard Assessment for Access Road to dam “Sveta Petka” using Rockfall Hazard Rating System (RHRS)

Large number of roads in our country are constructed in mountainous and hilly terrains. Execution of cuts in the hard rock masses is inevitable. In light of the geological nature of the rocks, processes like rockfalls and landslides in different forms and magnitude are very usual. They occur during construction activities and afterwards in exploitation of the roads. Correct protective measures must be undertaken in order to secure the safety of traffic and people using this roads. One such case is the access road to Dam “Sv.Petka”, where constant rockfalls, result of great rupture tectonics and steep cut angles built in marbly limestones, endanger the safety of traffic and construction workers using this road. In order to stress out the hazard invoked by rockfalls and the need of protective measures, we used the well established Rockfall Hazard Rating System (RHRS). Posted speed limit has great influence. Along other possibilities that this method offers is the planning of annual programs for protection measures, with separation of most dangerous zones according the classification, before any undertaking of geotechnical analyses of slope stability. Further software modeling is needed in order to get a better understanding of the nature of rockfalls