Hayri ÜN - Academia.edu (original) (raw)

Papers by Hayri ÜN

Research paper thumbnail of Deği̇şi̇k Ti̇p Çi̇mentolarla Hazirlanan Harçlarin Eği̇lme Sonrasi Basinç Dayanimi İle Doğrudan Basinç Dayanimlarinin Karşilaştirilmasi

Research paper thumbnail of The Ceyhan Earthquake of June 27, 1998 and Design of Eartquake Resisting Buildings

Pamukkale University Journal of Engineering Sciences, 1998

Our country is under risk of earthquake, and it has lost extensive economical goods. In addition ... more Our country is under risk of earthquake, and it has lost extensive economical goods. In addition to this, the reality of buildings those had not been constructed earthquake resisting on seismic regions have come out. It is true that those kind of building have been constructed all over the country. In this paper the design of earthquake resisting buildings have been taken up. It is dwelled upon the buildings had damages in Adana-Ceyhan earthquake at 27th July 1998 and reasons of damages. The damages on the buildings are appreciated under the lights of principles of design of earthquake resisting. The important precautions that have to taken are grouped for not living those kind of tragic earthquake disasters.

Research paper thumbnail of Structural Defects Observed at State Buildings

Pamukkale University Journal of Engineering Sciences, 2007

Although, state buildings are designed with higher building importance factors with respect to ot... more Although, state buildings are designed with higher building importance factors with respect to other buildings, they are damaged and collapsed in medium and large scale earthquakes occurred throughout the 14 year period starting from 1992 Erzincan Earthquake. Buildings, used for medical, educational, governmental and security purposes, have to be non-damaged and they should satisfy immediate occupancy after design earthquakes. In this study, structural deficiencies in 105 state buildings, of which seismic vulnerability assessment has been done in recent years, are investigated. Examples of different problems, which are not observed in other buildings mostly, are given.

Research paper thumbnail of Effect of curing temperature and relative humidity on early age and hardened properties of SCC

Construction and Building Materials, 2018

h i g h l i g h t s Effect of curing conditions on SCC properties was assessed. 10°, 20°and 30°C ... more h i g h l i g h t s Effect of curing conditions on SCC properties was assessed. 10°, 20°and 30°C and 40 and 80% of RH were considered. Temperature sped-up reaction, microstructure and mechanical properties. Lower RH increased evaporation, shrinkage and hydration speed. Hot-wet and cold-dry conditions increased compressive strength.

Research paper thumbnail of Evaluations on the relation of RC building damages with structural parameters after May 19, 2011 Simav (Turkey) earthquake

Natural Hazards, 2013

ABSTRACT An earthquake has struck Simav, Kutahya, located in the western part of Turkey on May 19... more ABSTRACT An earthquake has struck Simav, Kutahya, located in the western part of Turkey on May 19, 2011. This paper focuses on the evaluation of the regional damage data and detailed investigation on a set of selected reinforced concrete buildings in Simav county center. The soil properties in Simav are examined in detail using multi-channel analysis of surface wave measurements, boreholes and laboratory test data. The damages are observed to be independent of soil conditions being hilly or plain, both in regional and Simav county center level. However, a slight relation is observed: as the soil period increases, so does the damage. The most damaged buildings are the four story buildings, resembling the case after some other earthquakes in Turkey. Regarding the detailed numerical evaluations on the building set, the properties highly correlated with seismic damage are investigated. Based on the obtained findings, it is concluded that the global building properties may not be enough to establish a strong relation with damage due to the local damages at the structural member level, especially for smaller seismic events.

Research paper thumbnail of Experimental evaluation of concrete strength in existing buildings

Magazine of Concrete Research, 2008

An extensive field and laboratory study is carried out to evaluate the concrete strength of exist... more An extensive field and laboratory study is carried out to evaluate the concrete strength of existing building stock in Turkey. The concrete strength of each building was determined by core sampling and laboratory testing. Randomly selected components for core sampling were identified to meet with minimum requirements of standards or pre-standards for number of tests. A total of 1679 randomly selected core samples were extracted from 167 public buildings for laboratory testing. The average and coefficient of variation values of each building were obtained. The upper-bound value of the expected concrete strength is calculated as the mean less one standard deviation. It is observed that the expected concrete strength values are drastically lower than the specified ones. Also, the variability in concrete strength values is considerably high compared to the specified strength of buildings. Almost one-half of the investigated buildings have concrete strength values as low as that of the c...

Research paper thumbnail of A discussion of the paper “Use of zeolite, coal bottom ash and fly ash as replacement materials in cement production” by F. Canpolat, K. Yılmaz, M.M. Köse, M. Sümer, M.A. Yurdusev

Cement and Concrete Research, 2005

Canpolat et al. have presented a detailed study about the use of pozzolanic materials in cement p... more Canpolat et al. have presented a detailed study about the use of pozzolanic materials in cement production. Unfortunately some of their interpretations about zeolite replacement are misleading due to the facts listed below:

Research paper thumbnail of Kamu Yapilarinda Gözlenen Yapisal Kusurlar

Pamukkale University Journal of Engineering Sciences, Mar 15, 2011

ÖZET 1992 Erzincan depremi ile başlayan ve günümüze kadar geçen 14 yıllık süre içerisinde yaşamış... more ÖZET 1992 Erzincan depremi ile başlayan ve günümüze kadar geçen 14 yıllık süre içerisinde yaşamış olduğumuz orta ve büyük ölçekli depremlerde, daha yüksek bina önem katsayıları ile tasarlanmalarına rağmen kamu yapılarının da diğer yapılar gibi hasar gördüğü ve yıkıldığı görülmüştür. Sağlık, eğitim, yönetim ve güvenlik amacıyla kullanılan binaların özellikle tasarım depreminde hasar görmemesi ve deprem sonrasında da hemen kullanılabilir durumda olması gereklidir. Bu çalışmada; son yıllarda deprem dayanımları incelenen 105 kamu yapısında taşıyıcı sistem kusurları incelenmiştir. Karşılaşılan kusurlar örneklenmiştir. Diğer yapılarda pek gözlenmeyen bazı değişik problemlere ait örnekler verilmiştir.

Research paper thumbnail of 27 Hazi̇ran 1988 Ceyhan Depremi̇ Ve Depreme Dayanikli Yapi Tasarimi

Our country is under risk of earthquake, and it has lost extensive economical goods. In addition ... more Our country is under risk of earthquake, and it has lost extensive economical goods. In addition to this, the reality of buildings those had not been constructed earthquake resisting on seismic regions have come out. It is true that those kind of building have been constructed all over the country. In this paper the design of earthquake resisting buildings have been taken up. It is dwelled upon the buildings had damages in Adana-Ceyhan earthquake at 27th July 1998 and reasons of damages. The damages on the buildings are appreciated under the lights of principles of design of earthquake resisting. The important precautions that have to taken are grouped for not living those kind of tragic earthquake disasters.

Research paper thumbnail of Deği̇şi̇k Ti̇p Çi̇mentolarla Hazirlanan Harçlarin Eği̇lme Sonrasi Basinç Dayanimi İle Doğrudan Basinç Dayanimlarinin Karşilaştirilmasi

Research paper thumbnail of The Ceyhan Earthquake of June 27, 1998 and Design of Eartquake Resisting Buildings

Pamukkale University Journal of Engineering Sciences, 1998

Our country is under risk of earthquake, and it has lost extensive economical goods. In addition ... more Our country is under risk of earthquake, and it has lost extensive economical goods. In addition to this, the reality of buildings those had not been constructed earthquake resisting on seismic regions have come out. It is true that those kind of building have been constructed all over the country. In this paper the design of earthquake resisting buildings have been taken up. It is dwelled upon the buildings had damages in Adana-Ceyhan earthquake at 27th July 1998 and reasons of damages. The damages on the buildings are appreciated under the lights of principles of design of earthquake resisting. The important precautions that have to taken are grouped for not living those kind of tragic earthquake disasters.

Research paper thumbnail of Structural Defects Observed at State Buildings

Pamukkale University Journal of Engineering Sciences, 2007

Although, state buildings are designed with higher building importance factors with respect to ot... more Although, state buildings are designed with higher building importance factors with respect to other buildings, they are damaged and collapsed in medium and large scale earthquakes occurred throughout the 14 year period starting from 1992 Erzincan Earthquake. Buildings, used for medical, educational, governmental and security purposes, have to be non-damaged and they should satisfy immediate occupancy after design earthquakes. In this study, structural deficiencies in 105 state buildings, of which seismic vulnerability assessment has been done in recent years, are investigated. Examples of different problems, which are not observed in other buildings mostly, are given.

Research paper thumbnail of Effect of curing temperature and relative humidity on early age and hardened properties of SCC

Construction and Building Materials, 2018

h i g h l i g h t s Effect of curing conditions on SCC properties was assessed. 10°, 20°and 30°C ... more h i g h l i g h t s Effect of curing conditions on SCC properties was assessed. 10°, 20°and 30°C and 40 and 80% of RH were considered. Temperature sped-up reaction, microstructure and mechanical properties. Lower RH increased evaporation, shrinkage and hydration speed. Hot-wet and cold-dry conditions increased compressive strength.

Research paper thumbnail of Evaluations on the relation of RC building damages with structural parameters after May 19, 2011 Simav (Turkey) earthquake

Natural Hazards, 2013

ABSTRACT An earthquake has struck Simav, Kutahya, located in the western part of Turkey on May 19... more ABSTRACT An earthquake has struck Simav, Kutahya, located in the western part of Turkey on May 19, 2011. This paper focuses on the evaluation of the regional damage data and detailed investigation on a set of selected reinforced concrete buildings in Simav county center. The soil properties in Simav are examined in detail using multi-channel analysis of surface wave measurements, boreholes and laboratory test data. The damages are observed to be independent of soil conditions being hilly or plain, both in regional and Simav county center level. However, a slight relation is observed: as the soil period increases, so does the damage. The most damaged buildings are the four story buildings, resembling the case after some other earthquakes in Turkey. Regarding the detailed numerical evaluations on the building set, the properties highly correlated with seismic damage are investigated. Based on the obtained findings, it is concluded that the global building properties may not be enough to establish a strong relation with damage due to the local damages at the structural member level, especially for smaller seismic events.

Research paper thumbnail of Experimental evaluation of concrete strength in existing buildings

Magazine of Concrete Research, 2008

An extensive field and laboratory study is carried out to evaluate the concrete strength of exist... more An extensive field and laboratory study is carried out to evaluate the concrete strength of existing building stock in Turkey. The concrete strength of each building was determined by core sampling and laboratory testing. Randomly selected components for core sampling were identified to meet with minimum requirements of standards or pre-standards for number of tests. A total of 1679 randomly selected core samples were extracted from 167 public buildings for laboratory testing. The average and coefficient of variation values of each building were obtained. The upper-bound value of the expected concrete strength is calculated as the mean less one standard deviation. It is observed that the expected concrete strength values are drastically lower than the specified ones. Also, the variability in concrete strength values is considerably high compared to the specified strength of buildings. Almost one-half of the investigated buildings have concrete strength values as low as that of the c...

Research paper thumbnail of A discussion of the paper “Use of zeolite, coal bottom ash and fly ash as replacement materials in cement production” by F. Canpolat, K. Yılmaz, M.M. Köse, M. Sümer, M.A. Yurdusev

Cement and Concrete Research, 2005

Canpolat et al. have presented a detailed study about the use of pozzolanic materials in cement p... more Canpolat et al. have presented a detailed study about the use of pozzolanic materials in cement production. Unfortunately some of their interpretations about zeolite replacement are misleading due to the facts listed below:

Research paper thumbnail of Kamu Yapilarinda Gözlenen Yapisal Kusurlar

Pamukkale University Journal of Engineering Sciences, Mar 15, 2011

ÖZET 1992 Erzincan depremi ile başlayan ve günümüze kadar geçen 14 yıllık süre içerisinde yaşamış... more ÖZET 1992 Erzincan depremi ile başlayan ve günümüze kadar geçen 14 yıllık süre içerisinde yaşamış olduğumuz orta ve büyük ölçekli depremlerde, daha yüksek bina önem katsayıları ile tasarlanmalarına rağmen kamu yapılarının da diğer yapılar gibi hasar gördüğü ve yıkıldığı görülmüştür. Sağlık, eğitim, yönetim ve güvenlik amacıyla kullanılan binaların özellikle tasarım depreminde hasar görmemesi ve deprem sonrasında da hemen kullanılabilir durumda olması gereklidir. Bu çalışmada; son yıllarda deprem dayanımları incelenen 105 kamu yapısında taşıyıcı sistem kusurları incelenmiştir. Karşılaşılan kusurlar örneklenmiştir. Diğer yapılarda pek gözlenmeyen bazı değişik problemlere ait örnekler verilmiştir.

Research paper thumbnail of 27 Hazi̇ran 1988 Ceyhan Depremi̇ Ve Depreme Dayanikli Yapi Tasarimi

Our country is under risk of earthquake, and it has lost extensive economical goods. In addition ... more Our country is under risk of earthquake, and it has lost extensive economical goods. In addition to this, the reality of buildings those had not been constructed earthquake resisting on seismic regions have come out. It is true that those kind of building have been constructed all over the country. In this paper the design of earthquake resisting buildings have been taken up. It is dwelled upon the buildings had damages in Adana-Ceyhan earthquake at 27th July 1998 and reasons of damages. The damages on the buildings are appreciated under the lights of principles of design of earthquake resisting. The important precautions that have to taken are grouped for not living those kind of tragic earthquake disasters.