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TUNCAY Ergün 《山地科学学报》2018,15(1):114-129
In this study, the mechanisms of slope instabilities triggered by engineering excavations at location of a planned tunnel portal in the northwest region of Turkey were assessed, and stability of the current slopes which has impacts on safety of a settlement (village) and agricultural fields was investigated. In the first stage of the study, in order to identify the geological units and structural properties of the sedimentary rocks in the area, to clarify the mechanisms of instabilities and to characterize discontinuity and rock mass properties field works were conducted. In this content, geotechnical boreholes, geophysical explorations between the boreholes, line surveys to explore discontinuity properties, preparation of slope profiles using topographical techniques and sampling of rock blocks and discontinuity planes were performed. In the second stage, laboratory tests were carried out on the samples to determine the geomechnical properties of the slope forming materials and discontinuities. Then, back analyses of the instabilities were made to assess the responsible shear strength parameters of the geological units during failures by considering laboratory shear test results too. Based on the backanalyses of the failures, the strength properties of the slope debris were estimated, and it has been clarified that the residual shear strength properties are the factors controlling slip mechanism along the beddings. Following the stability analyses, it is understood that a further instability along the mass or bedding planes in the failed and redesigned area are not expected, if the current slope geometry is not changed. However, safety factor calculated for the slope in the debris is 1.1 which is well below the recommended value in the literature. The minimum safety factor for currently stable slopes which were cut at the eastern part of the failed area is 1.22 which is also less than that suggested in literature. Some remedial measures such as mini-pile or slope flattening are suggested after analyses to increase the factor of safety for this part below the settlement. 相似文献
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Resat Ulusay Candan Gokceoglu Tamer Topal Harun Sonmez Ergün Tuncay Zeynal Abiddin Erguler Ozgu Kasmer 《Environmental Geology》2006,50(4):473-494
The Cappadocia Region of Central Anatolia having a very distinct culture is one of the attractive touristic sites of Turkey due to its spectacular and unique landforms and historical heritages. In this region, the structures carved into thick to massive tuffs survived and kept their original integrity for a number of centuries. Environmental and anthropological factors at the Cappadocia Region have been the main reasons for extensive subsurface and multi-purpose use in the past and present. In addition, thermal insulation properties of the tuffs make these rocks suitable for use in underground openings. The Kayakapi Neighborhood, located in the town of Urgüp, is one of the famous historical sites. This site is situated within the “Göreme National Park and the Rock Sites of Cappadocia” which was inscribed on the World Heritage List in 1985. In order to develop the tourism potential of this abandoned site while preserving its cultural and natural values, a natural environmental conservation and revitalization project was initiated. As an integral part of this project, in this study, environmental and engineering geological problems, including rock fall potential and stability of about 1,200 rock-hewn structures, were investigated and an inventory was prepared for the possible re-use of the underground openings and other structures at the site, and remedial measures were recommended. The assessments based on observations and experimental studies indicated that the tuffs do not show significant changes both perpendicular and parallel to layering, and discontinuities and rock weathering seem to be more important factors controlling the stability of rock-hewn structures. The major stability problems threatening the re-use of the openings are structurally-controlled block instabilities, overbreaks, and erosion and shearing of the pillars made of tuff. On the other hand, the area at the entrance of the site requires some protection measures such as the construction of a retaining wall, systematic bolting of rock slabs and removal of some blocks having rock fall potential. The inventory for the openings suggests that there are a number of openings that can be re-used after necessary remedial measures. 相似文献
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The October 23, 2011 M7.2 Tabanli- Van and November 9, 2011 M5.2 Edremit – Van earthquakes caused damage in a widespread area across the Van province in Turkey. The ground motions, the damage caused by these earthquakes and the recent progress related to recovery efforts are presented herein. First, the key properties of the recorded strong ground motions like spectral amplitudes and directionality are evaluated. The observed damage in the affected reinforced concrete and masonry structures are discussed. The set of common structural damage mechanisms(i.e., soft story failure, torsional response due to plan irregularity, short column failure, pull out failure, pounding) observed in the damaged buildings were identified. The relationship between the key structural properties and the extent of damage is investigated. The primary loss drivers across the region were identified to be the poor quality of workmanship and improper use of building materials. The results from the investigation suggest that a large portion of the loss could have been prevented if sufficient attention and care were given to the implementation of the design regulations and in particular to the construction practice. Lastly, the recent progress in the ongoing rebuilding activities is presented. 相似文献
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Deep and shallow structures of large pockmarks in the Turkish shelf, Eastern Black Sea 总被引：2，自引：1，他引：2
Circular and elongated pockmarks are present between 180- and 300-m water depths in the Eastern Black Sea shelf. The circular pockmarks have diameters of 50–120 m and the elongated pockmarks are 150–200 m wide with crater depths of 10–25 m. In deeper sediments, buried pockmarks were vertically stacked, indicating that the pockmarks developed under periodically varying overpressure conditions driven by the seismologically active North Anatolian Fault. Linear elongated pockmarks were formed by downslope tensional stretching, which caused linear weak zones together with strong seafloor currents acting as a connector of circular pockmarks. 相似文献
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İsmail İnce Ali Bozdağ M. Bahadır Tosunlar M. Ergün Hatır Mustafa Korkanç 《Environmental Earth Sciences》2018,77(11):420
Building stones have long been one of the most widely used construction materials in the world. Building stones used in historical monuments are deteriorated partly or completely depending on the environmental and atmospheric effects. In recent years, non-destructive test methods have been used to assess deterioration of building stones used in historical monuments. Gödene stone is one of the building stones being widely used in the historical buildings in the Konya region, Central Anatolia. The most deterioration effects are observed in the Ferit Pa?a Cistern among the historical structures built with Gödene stone in the region. The aim of this study is to assess the deteriorating effects in the street façade of the Ferit Pa?a Cistern via non-destructive testing methods (Schmidt hardness rebound value, P-wave velocity, humidity measurement and thermal imaging) and create maps of deteriorated features. Turkey’s historic places are integrated to Turkish culture, efforts are made to conserve heritage through rehabilitation. Therefore, this study will help developers and federal managers during the project planning stage by providing technical data. 相似文献
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Osman Parlak Michel Delaloye Ergüzer Bíngöl 《International Journal of Earth Sciences》1996,85(4):647-661
The Mersin ophiolite, represented by approximately 6-km-thick oceanic lithospheric section on the southern flank of the Taurus
calcareous axis, formed in the Mesozoic Neo-Tethyan ocean some time during Late Cretaceous in southern Turkey. The ultramafic
and mafic cumulates having over 3 km thickness consist of dunite ± chromite, wehrlite, clinopyroxenite at the bottom and pass
into gabbroic cumulates in which leucogabbro, olivine-gabbro and anorthosite are seen. Crystallization order is olivine (Fo91−80) ± chromian spinel (Cr# 60-80), clinopyroxene (Mg#95−77), plagioclase (An95.6−91.6) and orthopyroxene (Mg#68−77). Mineral chemistry of ultramafic and mafic cumulates suggest that highly magnesian olivines, clinopyroxenes and absence
of plagioclase in the basal ultramafic cumulates are in good agreement with products of high-pressure crystal fractionation
of primary basaltic melts beneath an island-arc environment. Major, trace element geochemistry of the cumulative rocks also
indicate that Mersin ophiolite was formed in an arc environment. Coexisting Ca-rich plagioclase and Forich olivine in the
gabbroic cumulates show arc cumulate gabbro characteristics. Field relations as well as the geochemical data support that
Mersin ophiolite formed in a supra-subduction zone tectonic setting in the southern branch of the Neo-Tethys in southern Turkey. 相似文献
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Since the commencement of mining at the Himmetoğlu coal mine, northwest Turkey, serious stability problems have led to interruptions
in mining and some environmental effects. A geotechnical investigation was initiated in 1997 and the significant factors that
influence the stability have been defined. This paper outlines the results of the field and laboratory studies associated
with the causes and mechanism of the slope instabilities and their environmental impacts. The possible remedial measures to
improve the stability and to minimize the environmental problems are also described. Back-analyses and data from long-term
monitoring indicate that the failures occur along two or three planar surfaces by combination of faults and localized strata
steepening adjacent to the faults. The stability is sensitive to changes in length of the lower part of the basal sliding
surface and shear strength of the bedding surfaces in the overburden. Suitable remedial measures include slope flattening
(i.e. staged bench stripping), proper drainage and spreading of a rock blanket on the pit floor to increase spoil pile stability.
Received: 18 April 2000 · Accepted: 15 August 2000 相似文献
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Tuffs have been used as a construction material possibly since ancient times. In Afyonkarahisar, Turkey, there are numerous buildings constructed by tuff. Tuff has been a local construction material, during the Roman, Seljuk and Ottoman periods. Even though tuffs have relatively low durability and low strength values compared to marble, etc., they have survived with no major deterioration failures on many historical buildings. It has also been preferred because of its high porous texture, lightweight and easy shaping and process properties in the building sector. Naturally, it would be easily affected by water and humidity because of its porous structure. However, having this kind of structure leads to poor durability properties due to keeping water in it. The main objective of this study was to evaluate the physical and mechanical properties of the tuff quarried from the region and possible water effect, which may lead to degradation of its strength and durability of the material, thereby shortening the life span of the building structure used. Samples, which were tested after exposing to water and the freeze and thaw effects, were measured at a certain time. In this study, uniaxial compressive strength and flexural strength tests were conducted on test samples. The test results indicate that water may deteriorate the tuff’s strength properties and durability of the materials in due time. 相似文献
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