Leakage Analysis of Deriner Dam (Artvin-Turkey) Using 3D Modeling

Mehmet Ozcelik,Fatih Tuzlu 대한토목학회 2018 KSCE JOURNAL OF CIVIL ENGINEERING Vol.22 No.8

Leakage in engineering structures is considered as one of the main issues. Analysis of the amount of water leakage can be useful inpreventing such events. Deriner Dam consists of a concrete arch dam with ancillary structures including tunnels, and an undergroundpowerhouse with an installed capacity of 670 MW. Leakage was observed on the powerhouse after the construction stage. For thispurpose, a number of geotechnical data (including rheological and mechanical properties of the grout mixes) were re-assessed toexamine the source of leaking. For determination of leakage source, graphics of grout curtain were prepared by using grouting chartswith the RockWorks v.16 program. Leakage zones were obtained according to the prepared graphics and showed on 3D model. Theresults show that temperature variation of grouting mixes is the primary cause of leakage and its effect observed in the undergroundpowerhouse wall of the Deriner Dam.

Performance evaluation of suspended ceiling systems using shake table test

Ozgur Ozcelik,Ibrahim S. Misir,Serhan Saridogan 국제구조공학회 2016 Structural Engineering and Mechanics, An Int'l Jou Vol.58 No.1

The national standard being used in Turkey for suspended ceiling systems (SCS) regulates material and dimensional properties but does not contain regulations regarding installation instructions which cause substandard applications of SCSs in practice. The lack of installation instructions would potentially affect the dynamic performance of these systems. Also, the vast majority of these systems are manufactured using substandard low-quality materials, and this will inevitably increase SCS related damages during earthquakes. The experimental work presented here focuses on the issue of dynamic performance of SCSs with different types of carrier systems (lay-on and clip-in systems), different weight conditions, and material-workmanship qualities. Moreover, the effects of auxiliary fastening elements, so called seismic perimeter clips, in improving the dynamic performance of SCSs were experimentally investigated. Results show that clip-in ceiling system performs better than lay-on system regardless of material and workmanship qualities. On the other hand, the quality aspect becomes the most important parameter in affecting the dynamic performance of lay-on type systems as opposed to tile weights and usage of perimeter clips. When high quality system is used, tile weight does not change the performance of lay-on system, however in poor quality system, tile weight becomes an important factor where heavier tiles considerably decrease the performance level. Perimeter clips marginally increase the dynamic performance of lay-on ceiling system, but it has no effect on the clip-in ceiling system under the shaking levels considered.

Criteria for the Selection of Construction Method at the Ovit Mountain Tunnel (Turkey)

Mehmet Ozcelik 대한토목학회 2016 KSCE JOURNAL OF CIVIL ENGINEERING Vol.20 No.4

The Ovit Mountain Tunnel (OMT) is an highway tunnel under construction at Mount Ovit between Ikizdere (Rize) and Ispir (Erzurum) in NE Turkey. It will be the country's longest tunnel about 14700 m long in twin tubes. This paper compares and assesses tunnel excavation by Tunnel Boring Machine (TBM) excavation or drill and blast method for the OMT. Rock mass and material characteristics were evaluated to identify the excavation method. The rock mass classification of the tunnel grounds was performed by utilizing the Rock Mass Rating (RMR), Q system and New Austrian Tunnelling Method (NATM) which was followed by a geotechnical investigation along the tunnel. Twelve boreholes with a total length of 1116.5 m were drilled to assist and verify rock mass classifications. Seventy five rock samples were obtained for mechanical test. TBM method was selected at preliminary design stage of the OMT. But now, the OMT is driven by drill and blast method, using hydraulic excavators and the support is based on the principles of the NATM. The selection of this tunnelling excavation method was decided by morphological site conditions, geological, geotechnical site conditions, time and economic criteria.

Design of buckling restrained braces with composite technique

Ramazan Ozcelik,Yagmur Dikiciasik,Kazim B. Civelek,Elif F. Erdil,Ferhat Erdal 국제구조공학회 2020 Steel and Composite Structures, An International J Vol.35 No.5

This paper focus on the buckling restrained braces (BRBs) with new casing members (CMs). Seven BRBs with CMs consisting of precast concrete modules (PCMs) were tested to investigate the effects of CMs on the cyclic performance of BRBs. The PCMs consisted of plain and reinforced concrete casted into wooden or steel molds than they were located on the core plate (CP) via bolts. There were 14 or 18 PCMs on the CP for each BRBs. The technique of the PCMs for the CM provides that the BRBs can be constructed inside the steel or reinforced concrete (RC) structures. In this way, their applications may be rapid and practical during the application of the retrofitting. The test results indicated that the cyclic performance of the BRBs was dominated by the connection strength and confinement of the PCMs. The BRBs with PCMs wrapped with fiber reinforced polymers (FRPs) sustained stable hysteretic performance up to a CP strain of 2.0 %. This indicates that the new designed BRBs with PCMs were found to be acceptable in terms of cyclic performance. Furthermore, the connection details, isolation materials and their application techniques have been also investigated for the improved BRB design in this study.

Post-COVID-19 pain syndrome: a descriptive study in Turkish population

Topal, Ilknur,Ozcelik, Necdet,Atayoglu, Ali Timucin The Korean Pain Society 2022 The Korean Journal of Pain Vol.35 No.4

Background: The new type of corona virus has a wide range of symptoms. Some people who have COVID-19 can experience long-term effects from their infection, known as post-COVID conditions. The authors aimed to investigate prolonged musculoskeletal pain as a symptom of the post-COVID-19 condition. Methods: This is a descriptive study on the patients who were diagnosed with COVID-19 in a university hospital, between March 2020 and March 2021. Patient records and an extensive questionnaire were used to obtain relevant demographic and clinical characteristics, including hospitalization history, comorbidities, smoking history, duration of the pain, the area of pain, and the presence of accompanying neuropathic symptoms. Results: Of the diagnosed patients, 501 agreed to participate in the study. Among the participants, 318 had musculoskeletal pain during COVID-19 infection, and 69 of them reported prolonged pain symptoms as part of their a post-COVID condition which could not be attributed to any other cause. The mean duration of pain was 4.38 ± 1.73 months, and the mean pain level was 7.2 ± 4.3. Neuropathic pain symptoms such as burning sensation (n = 16, 23.2%), numbness (n = 15, 21.7%), tingling (n = 10, 14.5%), stinging (n = 4, 5.8%), freezing (n = 1, 1.4%) were accompanied in patients with prolonged musculoskeletal pain. Conclusions: Patients with COVID-19 may develop prolonged musculoskeletal pain. In some patients, neuropathic pain accompanies it. Awareness of prolonged post-COVID-19 pain is crucial for its early detection and management.

Integrating OpenSees with other software - with application to coupling problems in civil engineering

Gu, Quan,Ozcelik, Ozgur Techno-Press 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.40 No.1

Integration of finite element analysis (FEA) software into various software platforms is commonly used in coupling systems such as systems involving structural control, fluid-structure, wind-structure, soil-structure interactions and substructure method in which FEA is used for simulating the structural responses. Integrating an FEA program into various other software platforms in an efficient and simple way is crucial for the development and performance of the entire coupling system. The lack of simplicity of the existing integration methods makes this integration difficult and therefore entails the motivation of this study. In this paper, a novel practical technique, namely CS technique, is presented for integrating a general FEA software framework OpenSees into other software platforms, e.g., Matlab-$Simulink^{(R)}$ and a soil-structure interaction (SSI) system. The advantage of this integration technique is that it is efficient and relatively easy to implement. Instead of OpenSees, a cheap client handling TCL is integrated into the other software. The integration is achieved by extending the concept of internet based client-server concept, taking advantage of the parameterization framework of OpenSees, and using a command-driven scripting language called tool command language (TCL) on which the OpenSees' interface is based. There is no need for any programming inside OpenSees. The presented CS technique proves as an excellent solution for the coupling problems mentioned above (for both linear and nonlinear problems). Application examples are provided to validate the integration method and illustrate the various uses of the method in the civil engineering.

Elastic Scattering of Ultra-Cold Bosonic Fr Isotopes

M. Kemal OZTURK,Suleyman OZCELIK 한국물리학회 2008 THE JOURNAL OF THE KOREAN PHYSICAL SOCIETY Vol.52 No.2

Studies of the total elastic, spin-change and diffusion cross sections in elastic collisions of bosonic Fr isotopes at ultra-cold temperatures are reported. Parametric interaction potentials for singlet and triplet states of Fr isotopes are constructed and used in calculations of the detailed elastic scattering of Fr isotopes in the shape resonance region. As functions of energy, the elastic, spin-change and diffusion cross sections show considerable structure and are large in the limit of low temperature. For temperatures from 32 pico K to 3~K, we compare the numeric and the semiclassical results. Even at temperatures of a few degrees Kelvin, the spin-change and the diffusion cross sections are large and could provide an efficient way to produce condensed Fr. Studies of the total elastic, spin-change and diffusion cross sections in elastic collisions of bosonic Fr isotopes at ultra-cold temperatures are reported. Parametric interaction potentials for singlet and triplet states of Fr isotopes are constructed and used in calculations of the detailed elastic scattering of Fr isotopes in the shape resonance region. As functions of energy, the elastic, spin-change and diffusion cross sections show considerable structure and are large in the limit of low temperature. For temperatures from 32 pico K to 3~K, we compare the numeric and the semiclassical results. Even at temperatures of a few degrees Kelvin, the spin-change and the diffusion cross sections are large and could provide an efficient way to produce condensed Fr.

Experimental work on seismic behavior of various types of masonry infilled RC frames

I. Serkan Misir,Ozgur Ozcelik,Sadik Can Girgin,Serap Kahraman 국제구조공학회 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.6

Reinforced concrete frame structures with masonry infill walls constitute the significant portion of the building stock in Turkey. Therefore it is very important to understand the behavior of masonry infill frame structures under earthquake loads. This study presents an experimental work performed on reinforced concrete (RC) frames with different types of masonry infills, namely standard and locked bricks. Earthquake effects are induced on the RC frames by quasi-static tests. Results obtained from different frames are compared with each other through various stiffness, strength, and energy related parameters. It is shown that locked bricks may prove useful in decreasing the problems related to horizontal and vertical irregularities defined in building codes. Moreover tests show that locked brick infills maintain their integrity up to very high drift levels, showing that they may have a potential in reducing injuries and fatalities related to falling hazards during severe ground shakings.

Integrating OpenSees with other software - with application to coupling problems in civil engineering

Quan Gu,Ozgur Ozcelik 국제구조공학회 2011 Structural Engineering and Mechanics, An Int'l Jou Vol.40 No.1

Integration of finite element analysis (FEA) software into various software platforms is commonly used in coupling systems such as systems involving structural control, fluid-structure, windstructure, soil-structure interactions and substructure method in which FEA is used for simulating the structural responses. Integrating an FEA program into various other software platforms in an efficient and simple way is crucial for the development and performance of the entire coupling system. The lack of simplicity of the existing integration methods makes this integration difficult and therefore entails the motivation of this study. In this paper, a novel practical technique, namely CS technique, is presented for integrating a general FEA software framework OpenSees into other software platforms, e.g., Matlab-Simulink® and a soil-structure interaction (SSI) system. The advantage of this integration technique is that it is efficient and relatively easy to implement. Instead of OpenSees, a cheap client handling TCL is integrated into the other software. The integration is achieved by extending the concept of internet based client-server concept, taking advantage of the parameterization framework of OpenSees, and using a command-driven scripting language called tool command language (TCL) on which the OpenSees' interface is based. There is no need for any programming inside OpenSees. The presented CS technique proves as an excellent solution for the coupling problems mentioned above (for both linear and nonlinear problems). Application examples are provided to validate the integration method and illustrate the various uses of the method in the civil engineering.

Experimental work on seismic behavior of various types of masonry infilled RC frames

Misir, I. Serkan,Ozcelik, Ozgur,Girgin, Sadik Can,Kahraman, Serap Techno-Press 2012 Structural Engineering and Mechanics, An Int'l Jou Vol.44 No.6

Reinforced concrete frame structures with masonry infill walls constitute the significant portion of the building stock in Turkey. Therefore it is very important to understand the behavior of masonry infill frame structures under earthquake loads. This study presents an experimental work performed on reinforced concrete (RC) frames with different types of masonry infills, namely standard and locked bricks. Earthquake effects are induced on the RC frames by quasi-static tests. Results obtained from different frames are compared with each other through various stiffness, strength, and energy related parameters. It is shown that locked bricks may prove useful in decreasing the problems related to horizontal and vertical irregularities defined in building codes. Moreover tests show that locked brick infills maintain their integrity up to very high drift levels, showing that they may have a potential in reducing injuries and fatalities related to falling hazards during severe ground shakings.