Civil Engineering / İnşaat Mühendisliği

Permanent URI for this collectionhttps://hdl.handle.net/11147/13

Browse

Filters

2016 - 201932020 - 20221

Settings

Access Right: Open AccessPublisher: search.filters.publisher.CRC Press

Search Results

Now showing 1 - 4 of 4
  • Conference Object
    Citation - Scopus: 2
    A Critical Evaluation of Proxy Measures Used To Quantify Excavation-Induced Damage in Masonry Buildings
    (CRC Press, 2022) Liu, Yiyan; Gülen, Burcu; Açıkgöz, Sinan; Burd, Harvey; Gilson, Ben; İlki, Alper; Dalgıç, Korhan Deniz
    Building response during nearby excavation activities (e.g., tunnelling or deep excavations) is traditionally monitored by conducting displacement measurements. These displacement data are then post-processed to determine proxy measures that are correlated to damage categories. For masonry buildings, commonly-used proxy measures include building deflection ratio, horizontal relative displacement and angular distortion; simple mechanical models and empirical rules are used to define limiting values for these proxy measures to identify and control the level of cracking in buildings during construction. This procedure has a profound influence on mitigation and construction activities, and a critical evaluation of its veracity is needed. To this end, results from a recent experimental campaign on the settlement response of half-scale masonry buildings are examined in this paper. During these tests, detailed optical measurements were conducted, allowing the calculation of absolute displacements across the façade, as well as crack opening displacements at specific locations. These measurements facilitate a direct comparison between the actual observed damage and the damage category that is indicated by the proxy measures. The comparisons highlight the limitations of existing techniques. A discussion is provided on how proxy measure calculations can be improved to deliver more reliable indications of building damage. © 2022 the Author(s).
  • Conference Object
    Citation - WoS: 1
    Citation - Scopus: 2
    Structural Comparison of Scissor-Hinge Linkages
    (CRC Press, 2019) Maden, Feray; Akgün, Yenal; Yücetürk, Kutay; Aktaş, Engin; Yar Uncu, Müjde; Mitropoulou, C.
    Deployable structures can deploy from a compact to an expanded configuration by changing their sizes. The behaviors of these structures depend on some parameters such as geometric shape, member sizes and kinematic properties. To provide the deployment, not only the arrangements of structural members but also some restrictions must be considered. Moreover, contiguous members of the structures must let the large rotations to provide the transformation between different geometric forms from fully folded to fully deployed configurations. These requirements have an important impact on the fundamental properties of the structures related with structural performance, such as stiffness and strength. In this paper, stiffness of different scissor-hinge linkages are analyzed and compared. These linkages cover the same span with almost the same geometry and have the unit elements with same size and same weight. However, the geometry of unit elements is different from each other. The paper investigates the effect of this difference on the stiffness of whole system. © 2019 Taylor & Francis Group, London.
  • Conference Object
    Citation - Scopus: 2
    Naturally Occurring Arsenic in Geothermal Systems in Turkey
    (CRC Press, 2018) Baba, Alper
    Human beings have been benefiting from geothermal energy for different uses since the dawn of the civilization in many parts of the world. One of the earliest uses of geothermal energy was for heating and was used extensively by Romans in Turkey, where is an area of complex geology with active tectonics and high geothermal potential. The highest concentrations of naturally occurring aqueous arsenic (As) are found in certain types of geothermal waters, which are generally related to faults and alteration zone. The especially volcanic activity led to the delineation of wide-ranging areas of alteration within mineral assemblages, from advanced argillic type to silica type to prophylitic type at deep levels. The advanced argillic alteration zones are typified by enrichment of sulfur in volcanic rocks that have been dominant in the geological formation of Turkey and the primary mechanism for the presence of numerous trace elements in earth's crust, including but not limited to arsenic. Also, secondary epithermal gypsum has a high concentration of As in the form of realgar and orpiment along the fracture zones of metamorphic and carbonate aquifers. The temperature of geothermal fluid ranges from 40 to 295 degrees C in Turkey. The high arsenic concentrations in geothermal resources have been detected in different part of Turkey from 1 to 6000 mu g L-1 in geothermal fluids.
  • Conference Object
    Citation - Scopus: 4
    High Arsenic Levels in Groundwater Resources of Gediz Graben, Western Turkey
    (CRC Press, 2016) Baba, Alper; Gündüz, Orhan; Şimşek, Celalettin; Elçi, Alper; Sözbilir, Hasan; Murathan, Alim
    Gediz Graben situated in western Turkey is an area containing extensional structures with active tectonics and geothermal systems that serves as a suitable environment for the presence of high levels of arsenic (As) in groundwater. The results of a comprehensive monitoring program in the basin revealed that the maximum As concentration detected during the monitoring program was 3086 ppb and the average value was calculated to be 23.63 ppb. In addition, As levels in 28% of the water samples were above the 10 ppb limit value making them unsuitable for drinking water supply. These high As concentrations in the basin was mostly associated with long detention times of water in altered rocks located along detachment faults, strong water–rock interaction processes in the alteration zones and anthropogenic influences made within the geothermal fluid reservoir. © 2016 Taylor & Francis Group, London.