8 research outputs found
Liquefaction Probabilities Of Semani Area, In Albania Corresponding To Different Levels Of Safety
In this paper the liquefaction potential of Quaternary soft non-cohesive soils at Semanisite, Fier prefecture in Albania has been assessed.The liquefaction analyses have been computed considering the hazard levelcorresponding to different levels of safety, such as 10% in 10 years (72-years Return Period),10% in 50 years (475-years RP) and 2% in 50 years (2475-years RP). The accelerations corresponding to the abovementioned hazard levels are calculated using PSHA (probabilistic seismic hazard assessment), and The Cyclic Stress Ratio is calculated for each acceleration.The seismological data used in the analyses considers earthquakes with MS 4.5 and covers atime span from 58 up to 2009.The calculation of cyclic resistance ratio (CRR) of the soils is based on 416 SPT(Standard Penetration Test) values, 12 CPTU tests up to 25 m depth and shear wave velocity(Vs) measurements.The liquefaction probabilities for a given seismic event are combined with the probability of occurrence of the seismic event i
Seismic Risk Management Of An Elementary School Building Based On Minimum Expected Life-Cycle Cost
In earthquake disaster prevention, one serious problem confronting the world's earthquake - prone countries is seismic performance of buildings. A building is expected to remain safe and provide its intended function throughout its life span, with only small performance interruptions or damage due to earthquakes.It is necessary to identify buildings that are in risk and carry out their reconstruction or seismic retrofit in order to provide more strength and ductility. However the seismic retrofits come to a premium. Therefore, seismic retrofit of buildings entails an important risk-management decision problem as an optimal balance between the cost for the reinforcement and the future risks that must be achieved.This paper presents a decision methodology in seismic risk management considering only one fundamental risk, the cost imposed on the decision maker. The risk is expressed as the expected life-cycle cost, which is the expected amount of payments during the life of the building. These include the initial costs of the design and its construction, the additional cost for the reinforcement and the expected cost of damages generated due to earthquakes during the life span of the building.As an example, the proposed methodology is applied to an actual school building newly designed in Lushnja. The seismic evaluation of building is realized through the Japanese seismic screening method for seismic safety evaluation of existing reinforced concrete buildings. The actual cost of existing building and the additional cost for strengthening by using shear walls are estimated. In this case study, it is examined the cost effectiveness of shear walls used for strengthening of the school building in reducing the life-cycle cos
An Application Of The Aftershock Probability Evaluation Methods For Recent Albania Earthquakes Based On Gutenberg-Richter And Modified Omori Models
In this study, an assessment on the aftershock occurrence probability based on the combination of Gutenberg-Richter and modified Omori formulae is made in order to forecast how many large aftershocks should follow small main shocks and in order to evaluate aftershock probability that a randomly chosen event is greater than or equal to a certain magnitude of aftershock. For this purpose, we made an application of aftershock probability evaluation methods to nine aftershock sequences in which occurred Albania between 2004 and 2009 with magnitude level between 4.5 and 5.0
Shoreline Dynamics And Preventive Measures At Southern Part Of Durresi Bay
One of the most important aspects of coastal management and planning programs thatneeds to be investigated is shoreline dynamics. Long-term coastal analysis uses historical datato identify the sectors along the coast where the shoreline position has changed.At the southern part of Durresi Bay, the sandy beach has suffered strong erosions for thelast 20 years. In particular, in different segments situated at Karpen - Qerret lowland, duringthe last year the annual erosion rates reach values up to 30-37 m. The analysis of the coastal dynamics and spatiotemporal changes in the coastal morphology for the period between 1944and 2010 is an important tool to identify the principal factor of these changes and consequently to recommend the appropriate engineering interventions necessary to protectand recover the interested area.The present study takes advantage of geographical information system (GIS) tools tocontribute to the knowledge of the shoreline dynamics of the southern part of Durresi Bay.Shoreline changes were analyzed using the ArcGIS extension "Digital Shoreline AnalysisSystem" (DSAS). The length of the shoreline analyzed is about 3 km.Five shoreline position scorresponding to four time intervalswereanalyzed. These analyses are based on bathymetric studies, sediments and sediment transport analyses, and the mapping of the shoreline positionsfor the periods1944-1980, 1980-2007, 2007-2009and2009-2010.Annual rates of erosion, grain size distribution and the alongs
Application of the Erosion Potential Method in Vithkuqi Watersheds (Southeastern Albania)
Soil erosion is one of the most important phenomena affecting land composition and settlement. Among all natural causes of soil erosion such as rainfall intensity, temperature and wind, the human activity; massive deforestation and intensive agriculture, including the latest climate changes are considered as very important factors, especially nowadays. Thus, calculating the soil erosion coefficient appears very important in order to prevent the phenomena. Many methods are used to calculate such coefficient but in the presented research, the Erosion Potential Method was chosen. In this study, eight watersheds in southeastern Albania were evaluated. Results show that erosion is present in all considered watersheds. In one case (Panariti watershed) the erosion coefficient was very high; excessive, while in others it varies from heavy to very slight erosion. In conclusion, it can be stated that the Erosion Potential Method can be applied in the Albanian contest, same as in other neighbor countries. The results from Panariti, Roshani and Gianci should be further investigated due to the high quantity of soil eroded
Climate Change Effect on Soil Erosion in Vjosa River Basin
Soil erosion is closely related to climate changes, because changes to temperature and precipitation regimes may alter the erosivity of rainfall. The present study aimed to project future soil erosion phenomena in the Vjosa River Basin (VRB) using climate projections under the Representative Concentrations Pathway (RCP) 4.5 and 8.5 scenarios. SimCLIM model was used to perform the climate projection for the years 2035 and 2050, based on historical temperature and precipitation data (2000–2015). This investigation was carried out by using Erosion Potential Method EPM to estimate the effects of climate change on soil erosion in Vjosa River Basin, Albania. Results show an increase in average min and max annual temperature for both scenarios RCP4.5 and 8.5 by the end of 2050. The evaluation of the monthly precipitations for all RCPs reveals a likely decrease in summer precipitation, and a slight positive trend of winter precipitation for all time periods up to 2050. An increase in terms of eroded material and specific eroded material was estimated from the results of RCP4.5 and RCP8.5 scenarios. Thus, it can be stated that the study area has and will have a moderate erosion risk under these climate conditions
Stability assessment of a failed artificial embankment slope
This paper presents the stability problems of an artificial cohesion-less embankment slope supported on a saturated silty clay layer.In June 2011, an embankment about 9.00 m high started to be constructed in the Energetic Park of Porto Romano, in Durres city, Albania, as part of Preloading to Mitigate Seismic Risk project. The embankment, foreseen to be built in a conic trunk shape form, was to be used as a preload during the consolidation process of the site.Eighteen days after starting the construction process, when the embankment reached the height of 6.35 m, a soil stability failure of the embankment occurred. The calculations include the embankment slope stability analysis, during the design phase, considering the total height of the embankment (9.00 m) and at the moment of failure when the embankment height reached 6.35 m. The paper also presents the results of a back calculation of shear strength parameters at the moment of failure. Probability Based Design Method and Eurocode 7 Design Approaches are used during the analysis, considering long-term (drained) and short-term (undrained) conditions of the silty clay foundation