Faculty of Civil Engineering
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Item type:Publication, Detection and Monitoring of Slope Movement by Using Point Cloud Derived from the SfM Technique(University of Belgrade, Faculty of Mining ; Geology, 2024); ; Nikolovski, Toni - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Landslide Mapping and Zonation at National, Regional and Local Scale — Recent Experiences from Republic of Macedonia(University of Belgrade, Faculty of Mining ; Geology, 2024-05); ; - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Overview of applied methods for sustainable hydropower development at riverscale extent(Slovenian National Comitee on Large Dams- SLOCOLD, Macedonian Committee on Large Dams - MACOLD, 2020-12)Panovska F., Mitovski S., Petkovski L.onsidering latest rising temperatures of the atmosphere and increasing effect of burning fossil fuels for energy, climate has shifted and we have all witnessed unusual weather conditions. Since awareness has been raised on producing electricity with burning the fossils, water is seen on as a very reliable resource for renewable hydropower generation. It can cover peak hours electricity demands, but it can also cover base energy demands – unlike sun or wind energy which are highly unpredictable renewables in space and time. Human activities have polluted available fresh water, and rising population needs more and more by the day to survive. Agriculture is thriving and needs more water than ever to feed the growing population. However, as much as we need it, we also need to protect our homes from flash flood events occurring more and more often. This and more presents a picture of a very complex water resources systems planning and management problem. Every system needs to be planned with taking under consideration all related stakeholders. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Assessment of regular behavior and stability of tailings dams by comparing calculated and measured displacements(Slovenian National Committee on Large Dams-SLOCOLD, Macedonian Committee on Large Dams - MACOLD, 2020-12)Ljupcho Petkovski, Stevcho Mitovski, Frosina PanovskaThe tailings dams, due to the enormous volume of the waste lagoon, are earth-fill structures with highest potential hazard for the surrounding. However, the numerous reports of collapses of the tailings dams in the last three decades, indicate that the procedures and techniques in the design, construction, maintenance and technical monitoring of the embankment dams for water storage were not applied to the tailings dams, with the same carefulness and the proper caution. The comparison of the calculated and measured horizontal and vertical displacements in the tailings dam post-service period is necessary to make the valid conclusion about the regular behavior and for the satisfactory stability of these complex heterogeneous earth-fill structures. In this paper, the calculated displacements from the numerical model of the static analysis of the hydro tailings dam Topolnica are compared with the measured values from geodetic, as a part of the monitoring process. The combined tailings dam Topolnica of the copper/gold mine Buchim, Radovish, in the east part of RN Macedonia, is formed by downstream (in the first stage, dam No. 1) and upstream (in the second stage with two phases, dams No. 2-1 and No. 2-2) method of construction, with total height from the crest of the highest dam to the downstream toe of the dam of 141.2 m. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Stability analysis and required geometrical modification of tailings dam heightening subject to static liquefaction(Japan Commission on Large Dams, 2024)Ljupcho Petkovski, Stevcho Mitovski, Frosina PanovskaThe need to provide an additional volume for depositing tailings material, necessary for the regular operation of mines in conditions of spatial limitation, actualizes the heightening of the tailings storage facilities. The upgrade of the existing tailings storage facilities, with the upstream construction method of a new tailing sandy dams over the existing waste lagoon, is a heterogenic geo environment that is susceptible to liquefaction during static and dynamic (cyclic) loading and therefore they are the civil engineering structures with the highest stability risk. This upgrade is characterized by detailed geotechnical in-situ investigations, sophisticated structural analyzes (static, unsteady seepage, and dynamic), and modification of the geometry of tailings dam heightening, which are illustrated by the results of the stability investigation (in static conditions) of an upgrade of the existing up-stream diverting rockfill dam with clay core, with tailings sandy dam above the tailings deposition lake of the tailings storage facility Toranica, Kriva Palanka, Republic of North Macedonia, Europe. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, WATER ECONOMY PLANNING ON THE RIVER TRESKA BASIN BY SIMULATION MODEL(Slovak University of Technology in Bratislava, 2024-09)Stevcho Mitovski, Frosina Panovska Georgievska, Ljupcho Petkovski, Sonja GeorgievaWater management planning is crucial for long-term economic, social and environmental stability in civilized societies. One can only make plans with stored water, i.e. water impounded in reservoirs, formed with construction of dams. The process of long-term water planning and management includes creation of new reservoirs, adding new water users to existing reservoirs, as well as improved management of the existing reservoirs. Such analyses are done for the river Treska basin, located in the western part of R.N. Macedonia. With total basin area of 2068 km2 and average flow of Q=24,2 m3/s, currently there are three existing dams with reservoirs – Kozjak, St. Petka and Matka – supplying water for power production, as well providing flood protection of the city of Skopje. During the water economy planning process, four new reservoirs are planned – Greshnica, Podvis, Makedonski brod and Kalugjerica - in order to suffice the lack of fresh drinking water for the analysed basin, as well as water for irrigation of agricultural land for the upcoming 20 years. In order to oversee the new planned scheme for the river Treska basin, simulation model is prepared with application of HEC ResSim software. The simulation modelling is carried out on river scale extent, by inclusion of the existing and planned dams with reservoirs. The output results of the simulation model point out that the basin has enough capacity to suffice the water demands for water supply and irrigation, and in addition, it provides increased power production from renewable energy sources, for the next 20 years. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Seismic resistance assessment of a diverting rock-earth dam heightened with tailings dam(Greek Committee On Large Dams (GCOLD), 2024)Ljupcho Petkovski, Stevcho MitovskiThe need to provide an additional volume for depositing tailings material, necessary for the regular operation of mines in conditions of spatial limitation, actualizes the heightening of the tailings storage facilities. The upgrade of the existing tailings storage facilities, with the upstream construction method of a new tailing sandy dams over the existing waste lagoon, is a heterogenic geo environment that is susceptible to liquefaction during dynamic (cyclic) loading and therefore they are the civil engineering structures with the highest stability risk. This heightening is characterized by detailed geotechnical in-situ investigations, sophisticated structural analyses (static, non-steady seepage, and dynamic), and necessary modification of the geometry of the embankment. That is illustrated by the results of the dynamic analysis and seismic resistance assessment of a heightening of the existing upstream combined diverting dam and modification of the previous rockfill dam with clay core, with tailings sandy dam above the waste lagoon of the tailings storage facility Toranica, Kriva Palanka, Republic of North Macedonia. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, Safety of embankment dams in the case of upgrading the existing tailings storage facilities(CRC Press/Balkema, Taylor & Francis Group, 2023)Ljupcho Petkovski, Frosina Panovska, Stevcho MitovskiThe embankments over tailings dams and waste lagoons or the upgrade at the existing tailings storage facilities, from stability aspects of a heterogenic geo environment, has many similarities with the tailings dams with upstream construction method. These earth-fill structures are susceptible to liquefaction during static and dynamic (cyclic) loading and therefore they are civil engineering structures with the highest stability risk. The need to provide an additional volume for depositing tailings material, necessary for the regular operation of mines in conditions of spatial limitation, actualizes the upgrade of the tailings storage facilities. This upgrade is characterized by detailed geotechnical in-situ investigations and sophisticated structural analyses, which are illustrated by the results of the stability analyses (in static and dynamic conditions) of a dry stacking embankment above the tailings storage facility Sasa no. 2, Makedonska Kamenica, Republic of North Macedonia. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, PROGNOSIS ANALYSIS OF ARCH DAM BEHAVIOR BY HYBRID MODEL(Gdańsk University of Technology Publishing House, Gdańsk 2022, 2022)Frosina Panovska, Stevcho Mitovski, Ljupcho PetkovskiThe assessment of the structural stability and behavior of the dam during construction, at full reservoir and during the service period is of paramount importance for such structures. Each dam, in dependence of the type and dimensions, has installed system for technical monitoring that enables tracking of the dam behavior and assessment of the dam state throughout registration and interpretation of various data such as displacements, stresses, seepage etc. The case study is double curvature concrete arch dam, with asymmetric shape due to the valley topography. In the paper are systemized acknowledgments for the comparison of the recorded data from technical monitoring of the dam and output results from spatial (3D) numerical model, created by application by application of SOFiSTiK code, based on Finite Element Method. In addition, a Neural Network model is created by recorded data from the technical monitoring. The both models create the so called hybrid model. For both models are used input parameters such as variation of water level in the reservoir and air temperature, and the output results are compared with recorded values for water level in piezometers at specified nodes of the dam. The aim of the task is to compare and calibrate the output results from the both models and recorded values from the technical monitoring of the dam and to carry out prognosis modeling for the future behavior of the dam. - Some of the metrics are blocked by yourconsent settings
Item type:Publication, BEHAVIOUR OF EARTH DAM DURING RESERVOIR FILLING AND EARTHQUAKE ACTION, DAM IN SLOVENIA(Slovenian National Comitee on Large Dams- SLOCOLD, UNESCO Chair on Water-related Disaster Risk Reduction, University of Ljubljana, 2022)Ljupcho Petkovski, Stevcho Mitovski, Frosina PanovskaIn the static analysis of the earth zoned dam in Slovenia, for the state of rapid filling of the reservoir and lowering of the level for remediation of the dam, up to the state of long-term maintenance at normal level, which is a pre-earthquake state, an elastoplastic model with variable modulus of elasticity was used, for the local materials in the dam body. The analysis was performed in drained conditions with effective stresses, using combined mechanical and seepage analysis in the time domain. Criterion for calibration of nonlinear elastic material parameters is the condition that the horizontal displacements in the dam crest, for the condition of the first filling of the reservoir, are approximately the same with the measured values, i.e. about-120 mm in the downstream direction. The key conclusion from the static analysis is that the embankment dam, with the adopted geometry and composition of materials, possesses satisfactory static stability. In the analysis of the dynamic response of the dam, a nonlinear model is applied (equivalent linear analysis with inelastic material parameters), where the local materials are approximated with a variable maximum shear modulus. Permanent displacements during seismic excitation are determined by dynamic deformation analysis, where from the difference of the effective stresses in two successive time steps, incremental forces are determined, which result in corresponding deformations. The dynamic analysis confirms the seismic resistance of the embankment dam in the action of a design earthquake with PGA of 0.30 g, i.e. there is no danger of rapid and uncontrolled reservoir emptying, because the crest settlements from dynamic inertial forces for the duration of the earthquake are 1.1 m, apropos are much lower than the height above the normal level in the reservoir till dam crest, which is 3.2 m.