FARKLI ORTAMLARA MARUZ KALAN BAZI AHŞAP ESASLI LEVHALARIN MÜHENDİSLİK ÖZELLİKLERİNİN İNCELENMESİ

Günümüzde ahşap esaslı levhalar; kontrplak, mdf, sunta, ahşap dik yongalı levhalar, ahşap yatık yongalı levhalar, playwood vb. olarak sınıflandırılmaktadır. Bu çalışmada, farklı ortamlara maruz kalan ahşap esaslı levhalardan bazılarının mühendislik özeliliklerindeki değişimler incelenmiştir. Bu amaçla, yaygın kullanımları nedeniyle Yonga Levha (Sunta), Lif Levha ( MDF) ve Kontrplak levhalar farklı ortamlara maruz bırakılarak mühendislik özellikleri belirlenmiştir. Bu levhalardan TS EN 317’ye uygun olarak kenar uzunluğu 50±1 mm olan kare kesitli numuneler hazırlanmıştır. Bu numuneler;  şartlandırma, suya daldırma, dondurma, etüvde kurutma işlemlerine tabi tutulmuş ve her işlem sonunda boy, kalınlık, ağırlık, kalınlık doğrultusunda şişme oranları ile su emme oranları ölçülmüştür. Her malzeme için elde edilen deneysel sonuçlar o malzemenin referans değerleri ile karşılaştırılarak yorumlanmıştır. Buna göre, kontrplak için ortalama su emme ve kalınlık doğrultusunda şişme oranlarının sırasıyla %36.31 ve %5.26 olduğu, mdf için %20.38 ve %0.91 olduğu ve sunta için ise bu oranların %80.04 ve %7.24 olduğu belirlenmiştir.  Deneylerle elde edilen sonuçların malzeme grubuna göre istatistiksel olarak birbirinden farklı olup olmadığının belirlenmesi amacıyla da varyans analizi ve gruplar arası çoklu karşılaştırma testleri yapılmış ve analiz sonuçları referans değerlerle karşılaştırılmıştır

LASTİK AGREGALI BETONLARDA ELASTİSİTE MODÜLÜNÜN DENEYSEL VE TEORİK OLARAK İNCELENMESİ

Bu çalışmada, atık lastiklerden beton içinde kullanmak amacıyla ince ve iri lastik agregalar üretilmiştir. Bu lastik agregalar normal agrega ile sırasıyla % 5, 10, 15 ve 20 oranlarında hacimsel olarak yer değiştirilmek suretiyle lastik agregalı betonlar elde edilmiştir. Üretilen lastik agregalı betonların fiziksel ve mekanik özellikleri belirlenmiştir. Eğilmede çekme deneylerinin yapılabilmesi için 100x100x500 mm ebatlarında kiriş numuneler hazırlanmıştır. Bu numuneler eğilmede çekme deneylerine tabi tutularak deney esnasında kirişlerin orta noktalarından elde edilen sehim miktarları ölçülmüştür. Bu sehim miktarlarından faydalanarak üretilen lastik agregalı betonların elastisite modülleri belirlenmiştir. Ayrıca, üretilen lastik agregalı betonların elastisite modülleri çeşitli ülkelerin standartlarında önerilen ampirik formüllerle de hesaplanmıştır. Deneysel olarak belirlenen elastisite modülleri ile ampirik formüllerle hesaplanan elastisite modülleri arasındaki ilişki belirlenmeye çalışılmıştır. Sonuç olarak, betondaki lastik miktarı arttıkça deneysel verilerle hesaplanan elastisite modülleri ile ampirik formüllerle hesaplanan elastisite modülleri arasındaki ilişkinin azaldığı belirlenmiştir. Ancak, Amerika Beton Enstitüsü (ACI) tarafından önerilen formül ile deneysel olarak hesaplanan elastisite modülü arasında oldukça yüksek bir ilişki olduğu görülmüştür

Betonarme Bir Okul Binasının 2018 Deprem Yönetmeliğine Göre İncelenmesi

Bu çalışmada ülkemiz toprak alanlarının büyük bir çoğunluğu deprem bölgesinde olması nedeniyle Çevre ve Şehircilik Bakanlığı, deprem etkisi altında yeni binaların tasarımında ve mevcut binaların değerlendirilmesinde değişiklikler yaparak depreme dayanıklı yapıların inşa edilmesini hedeflemektedir. Bu amaçla 2018 Deprem yönetmeliği hazırlanmıştır. Yönetmelikte, mevcut binaların zemin özelliklerinin nasıl belirleneceği belirtilmiştir. Bu kapsamda, zemin grupları taşıma gücü açısından en yüksekten en düşüğe doğru A, B, C, D, E, F olarak 6 farklı grupta tanımlanmıştır. Bu çalışmada, 1999 Marmara ve Düzce depremlerinden etkilenmiş ve taşıma gücü yüksek bir zeminde inşa edilmiş bir okul binasının deprem performans analizi yapılmıştır. Binadaki taşıyıcı elemanların kapasiteleri belirlenmiş ve deprem dayanımları değerlendirilmiştir. Binanın içinde ve dışında temel muayene çukurları açılarak temel şekli ve boyutları belirlenmiştir. Sahada zeminin taşıma gücü ve bazı özelliklerin belirlenmesi amacıyla 3 adet sondaj kuyusu açılmıştır. Binanın taşıyıcı elemanları üzerinde donatı çap ve paspayları ölçülerek kolon ve kirişlerden yönetmelikte belirtilen sayıda karot numuneleri alınarak laboratuar ortamında beton basınç dayanımları bulunmuştur. Proje verilerinden elde edilen bilgiler 2018 yönetmeliğine göre “STA4-V14.1”  paket programı ile analiz edilmiştir

Fuzzy logic and statistical-based modelling of the Marshall Stability of asphalt concrete under varying temperatures and exposure times

WOS: 000265809500008In this study, the Marshall Stability(MS) of asphalt concrete under varying temperature and exposure times was modelled by using fuzzy logic and statistical method. This is an experimental study conducted using statistics and fuzzy logic methods. In order to investigate the Marshall Stability of asphalt concrete based on exposure time and environment temperature, exposure times of 1.5, 3.4.5 and 6 h and temperatures of 30,40 and 50 degrees C were selected. The MS of the asphalt concrete at 17 degrees C(in laboratory environment temperature) was used as reference. The results showed that the MS of the asphalt core samples decreased 40.16% at 30 degrees C after 1.5 h and 62.39% after 6 h. At 40 degrees C the decrease was 74.31% after 1.5 h, and 78.10% after 6 h. At 50 degrees C the stability of the asphalt decreased 83.22% after 1.5 h, 88.66% after 6 h. The relationships between experimental results, fuzzy logic model and statistical results exhibited good correlation. The correlation coefficient was R = 0.99 for fuzzy logic model and R(2) = 0.9 for statistical method. Based on the results Of the study, it could be said that both the fuzzy logic method and statistical methods could be used for modelling of the stability of asphalt concrete under varying temperature and exposure time. (C) 2008 Elsevier Ltd. All rights reserved

Determining the stability of asphalt concrete at varying temperatures and exposure times using destructive and non-destructive methods

This study examined the effect of varying temperatures and varying exposure times on the stability of asphalt conrete using destructive and non-destructive methods. The study also looked at the relationship between destructive and non-dcstructive methods. In order to investigate the stability according to exposure time and environment temperature, exposure times of 1.5, 3, 4.5 and 6 h and temperatures of 30, 40 and 50°C were selected. The results showed that at the environment temperature of 17°C the stability of the asphalt core samples decreased by 40.16% at 30°C after 1.5 h and 62.39% after 6 h. At 40°C the decrease was 74.31% after 1.5 and 78.10% after 6 h. At 50°C the stability of the asphalt decreased by 83.22% after 1.5 h and 88.66% after 6 h. The results also pointed to a moderate negative relationship (R = -0.533) between second ultrasound and stability indicating that non-destructive ultrasound method can be used to predict stability. © 2007 Asian Network for Scientific Information

Artificial neural network based modelling of the Marshall Stability of asphalt concrete

WOS: 000287419900154In this study, the Marshall Stability (MS) of asphalt concrete under varying temperature and exposure times was modeled by using artificial neural network. In order to investigate the MS based on physical properties, exposure time and environment temperature, exposure times of 1.5, 3, 4.5 and 6 h and temperatures of 30 degrees C, 40 degrees C and 50 degrees C were selected. The results showed that at the environment temperature of 17 degrees C the stability of the asphalt core samples decreased by 40.16% at 30 degrees C after 1.5 h and 62.39% after 6 h. At 40 degrees C, the decrease was 74.31% after 1.5 and 78.10% after 6 h. At 50 degrees C the stability of the asphalt decreased by 83.22% after 1.5 h, and 88.66% after 6 h. Experiment results and ANN model exhibited good correlation for this reason the ANN method could be used to model the MS. (C) 2010 Elsevier Ltd. All rights reserved

Prediction of ductulity on asphalt cement via fuzzy logic

Bu çalışmada, asfalt çimentosunun farklı sıcaklık ve bekleme sürelerine bağlı olarak duktulitesindeki değişim incelenmiştir. Bu amaçla AC 40 sınıfı asfalt çimentosu kullanılarak 15, 20 ve 25 oC sıcaklıklarda sırasıyla 1, 1.5 ve 2 saat bekletilerek 72 adet duktulite deneyi yapılmış ve deney sonuçları referans duktulite değerleri ile karşılaştırılarak aralarındaki ilişkiler belirlenmeye çalışılmıştır. Referans sıcaklığın ve bekleme sürelerinin sağlanamadığı şartlarda da duktulite deneylerinin yapılabilirliği gösterilmiş, deneylerle belirlenmemiş olan duktulite değerlerinin sıcaklık ve bekleme sürelerine bağlı olarak tahmin edilebilmesi için de Bulanık Mantık metoduyla tahmin modeli oluşturulmuş ve oluşturulan modelin bu amaçla kullanılabileceği gösterilmiştir.In this study, the changing of ductility for asphalt cement in different temperature and waiting times were researched. For this aim, by using AC40 asphalt cement 72 ductility experiments were conducted at 15, 20, and 25oC temperatures for 1, 1.5 and 2 waiting times respectively. Comparing the experimental results with references ductility values, the relationship between references value and experimental results tried to determine. It was showed that the ductility tests could be done in a condition that is not ensured the references temperature and waiting times. Also, by using Fuzzy Logic method, prediction model was constituted based on temperature and waiting time to predict the ductility of asphalt cement which could not be determined with experimental. It was showed that the prediction model could be used to predict the ductility of asphalt cement based on temperature and waiting time

INVESTIGATION OF THE EFFECT OF THE QUANTITY OF SODIUM HEXAMETAPHOSPATH TO THE HYDROMETER TEST RESULTS WITH EXPERIMENTAL AND STATISTICAL METHODS

WOS: 000273608200018In this study, the effect of quantity of sodium hexametaphosphate (NaPO(3)) to the soil grain' diameters were investigated as experimental and statistically. Hydrometer testing was conducted. 0, 10, 20, 30, 40, 50 and 60 gr NaPO(3) was respectively added into the prepared suspension. The specific gravity, pH and the conductivity were measured for each suspension. As pointed out in the TS 1900-1-2006 (Turkish Standard), the soil' grain diameter in the solution prepared with 40 gr NaPO(3) was used as reference. As a result, it was determined that the soil grain diameter in suspension added "0" gr NaPO(3) greater 4.51 time than the reference grain diameter. When respectively added 10 gr into the suspension, the soil' grain diameter greater 3.90 time than reference grain diameter, added 20 gr 3.46 time, and added 30 gr 2.12 time. Besides, the hydrometer reading could be done only 260(th) minute when added 50 gr in to the suspension. Moreover, the hydrometer couldn't be read in the solution prepared with 60 gr NaPO(3). The obtained data were analysed statistically by using SPSS programme and determined the correlation coefficients for the hydrometer test parameters (passing time, original hydrometer reading, temperature, pH, conductivity, The correction coefficient value for solving matter and temperature, corrected hydrometer reading, effective deep, value of the K, particle diameter and quantity of the NaPO3). Also, regression analysis was conducted (R=0.87) to predict the corrected hydrometer test reading based on the original hydrometer reading and the quantity of the NaPO(3)

Neural Network Based Modelling of Soil Particle Diameters Under Varying Quantity of Sodium Hexametaphosphate

WOS: 000264759100015In this Study, the particle diameter of the soil was simulated and modelled by using artificial neural network method. In order to determine the particle diameter of the soil based on passing time, hydrometer reading, temperature of the solution and the quantity of the sodium hexametaphosphate, the quantity of the sodium hexametaphosphate 0, 10, 20, 30, 40, 50 and 60 were respectively selected. As pointed out in the Turkish Standard 1900, the soil particle diameters in the solution prepared with 40 g sodium hexametaphosphate was taken as reference. It was found that the average soil grain diameter for 0 g sodium hexametaphosphate was about 4.5 times bigger than the reference grain diameter, for 10 g was 3.9 times, for 20 g 3.46 times, for 30 g 2.12 times bigger. However, the hydrometer reading could be done only up to the 260th min for 50 g sodium hexametaphosphate and for 60 g sodium hexametaphosphate the hydrometer couldn't be read. The relationships between experimental results and artiflicial neural network (ANN) model exhibited good correlation. The cot-relation coefficients square were found as R(2) = 0.99 for training set and R(2) = 0.94 for testing set with ANN. Based on the result, of the study, it could be said that the ANN method could be used for modelling of the particle diameter of the soil according to the passing time, hydrometer reading, temperature of the and the quantity of the sodium hexametaphosphate

MODELLING THE STABILITY OF ASPHALT CONCRETE WITH FUZZY LOGIC AND STATISTICAL METHODS FOR VARIOUS FREEZING AND THAWING CYCLES

WOS: 000276584200003The stability of asphalt concrete under the effects of freezing and thawing was studied experimentally, and the experimental test results were modelled using fuzzy logic and statistical methods. The stability was investigated experimentally using the Marshall and ultrasound methods. Asphalt core samples 10 cm in diameter were alternately frozen (-20 degrees C for 16 hr) and thawed (16 degrees C for 8 hr) for 5, 10, 15, 20, 25, and 30 cycles to simulate daily winter conditions. The stability of asphalt concrete at the laboratory environment temperature of 17 degrees C was used as a reference. The results showed that the stability of asphalt core samples exposed to freezing and thawing increased, and this increase varied between 22.7% and 19.2% for 5- and 30-day cycles, respectively. By using Fuzzy Logic and statistical methods, prediction models were constituted based on freezing-thawing cycle, bitumen ratio, saturated unit volume weight, volume of voids, air dry unit volume weight to predict the Stability of asphalt concrete which could not be determined with experimental. The experimental results, the fuzzy logic model, and the statistical results showed good correlations. For the stability of asphalt core samples, the correlation coefficient was R(2) = 0.88 for the fuzzy logic model and R(2) = 1.0 for the statistical method. Based on the results of this study, it is clear that both the fuzzy logic and statistical methods can be used to model the stability of asphalt concrete under various freezing and thawing conditions