Browsing by Author "Selçuk, L."

Now showing 1 - 4 of 4

Urban Flood Susceptibility Assessment of Central Districts of Van Province, Turkey, Using Geographic Information System (gis)-Based Multi Criteria Decision Analysis (Mcda)
(Hacettepe Universitesi Yerbilmleri, 2016) Selçuk, L.; Selçuk, A.S.; Kasapoğlu, D.
Van (Turkey) is one of the easily affected cities in the flooding. According to the latest 60-year statistical data, a total of 166 flood events were occurred in Van province and its districts. The most important reason for the flooding is the impermeable cover of residential areas and poor substructure systems within heavy rainfall in the spring which ground water level is close to the surface due to melting of snow. The scope of this study is to evaluate the flood susceptibility of the central district of Van, using multi-criteria decision analysis (CPL), and geographic information systems (GIS).The susceptibility model developed in this study contains six different factors. These are: lithology, the depth of groundwater table, distance to the discharge channels, slope, elevation (above mean sea level) and land-use. The susceptibility assessment is conducted by using a comparison matrix where all identified criteria of GIS layers are compared against each other. The acceptability and reliability of the model was determined using historical events. All of these events plotted over the model showed that there is a remarkable coincidence with high susceptibility areas. The flood susceptibility model shows that İpekyolu, central district of Van city, has much more flood hazard potential than those of other districts. High susceptibility to flooding in the study area is mainly related with flat terrain features so that the area has a low slope angle, impermeable lithology and the presence of urban stream channels with poor maintenance plan. Therefore, in order to prevent the possible flooding, site planning, improving the stream beds and substructure systems should be effectively integrated in potential areas. © 2016, Hacettepe Universitesi Yerbilmleri. All Rights Reserved.
Welding Intensity Assessment of Pyroclastic Units Based on Engineering Quality Requirements
(Springer Science and Business Media Deutschland GmbH, 2021) Selçuk, L.; Beyaz, T.
Changes to physical and mechanical properties of pyroclastic flow deposits occur during welding process, resulting from overburden pressure and temperature. A great deal of research has been carried out to identify which physical parameters can enable quantification of the degree of welding within pyroclastic deposits. Material properties, such as density, porosity, hardness, abrasion, and compressive and flexural strength, are critical in assessing the suitability of natural stone as a building material, but they have not been sufficiently integrated. Therefore, an attempt has been made to develop a welding classification which integrates measurements of material properties with petrographic and textural observations. The proposed classification covers physical, index, and strength parameters for pyroclastic flow deposits. The most important aspect of this investigation has been the quantification of material parameters and definition of a welding classification applicable to a wide range of ignimbrites, from nonwelded to densely welded, that are used as natural building stone. This welding classification is proposed to ensure a consistent approach in characterizing key aspects of welded facies in pyroclastic deposits and in the identification of natural stone reserves. © 2021, Saudi Society for Geosciences.
The Effect of Quaternary Alluvium on Strong Ground Motion: 2011van Earthquakes
(TMMOB - Jeoloji Muhendisleri Odasi, 2012) Selçuk, L.; Aydin, H.
The distribution of damaged buildings observed from October 23 and November 9, 2011 Van earthquakes shows that a major portion of damage occurred at settlement areas underlain by alluvial soils. The effect of alluvial soil on strong ground motion and structural damage can be seen by comparing two strong ground motion records of the Van province, earthquake of 09 November 2011 (Mw:5.6). One record at Edremit on travertine bedrock had a peak horizontal acceleration of 0.10 g. The other one, at the city center of Van province, at a distance of 15 km from the epicenter in Quaternary alluvium, had the accelaration value of 0.25 g. The effect of soil on the ground motion is about 2.5. In this study, the lateral and vertical distribution of the soil were obtained using a total of 81 geotechnical borehole data with depths ranging from 10-25 m. Soil amplification values computed at the alluvial site based on measured shear wave velocity show reasonably good agreement with the observed motions. The earthquake damage was determined to be high at local areas of relatively poor soil conditions such as cohesionles and loose soil, high groundwater. In addition to the soil conditions, there is no doubt that the use of low quality materials and low construction technologies have caused higher damage at central districts of Van province. Considering the soil conditions, both ground deformation (soil amplification, liquefaction) and cycling loading will increase the loss of lives and property in the central districts of Van province. Therefore, in order to minimize the possible damage of a potential earthquake, ground conditions should be considered at the Van settlement area.
Determination of Dynamic Soil Properties of Van Yuzuncu Yil University Campus for the Preparation of Microzonation Map
(TMMOB - Jeoloji Muhendisleri Odasi, 2015) Akin, M.K.; Akin, M.; Akkaya, İ.; Özvan, A.; Üner, S.; Selçuk, L.; Tapan, M.
One of the most important factors causing loss of life and property during earthquakes is the soil conditions that the structure is built on. Determination of the soil engineering properties for understanding the behavior of ground under dynamic loads and/or minimizing the losses that may occur is quite crucial. The earthquakes occured in our country especially in 1999 and later on, and the resulting loss of life and property once more emphasized the importance of the social and economic dimensions of the impact created by the earthquake. Dynamic soil properties must be studied in accordance with the principles of microzonation considering the natural disasters such as earthquake. For this aim, the dynamic soil properties of Van Yuzuncu Yil University campus area are determined. Liquefaction, soil amplification and the like for the campus area are investigated through field studies conducted in order to reveal the ground conditions, and consequently the suitability for settlement is evaluated to guide the future planning of the campus. © 2015, TMMOB - Jeoloji Muhendisleri Odasi. All Rights Reserved.