Zemin granülometrisinin ön konsolidasyon basıncı ve zemin hafızasına etkisi

TEZ5989Tez (Doktora) -- Çukurova Üniversitesi, Adana, 2006.Kaynakça (s.102-107) var.xiv, 107 s. : rnk. ; 29 cm.In this study, the effect of soil granulometry on preconsolidation pressure and soil memory was investigated. For this purpose, we prepared 10 mixtures having different proportions of sand and clay, placed the mixtures in molds, and to simulate overburden pressure, loads imposing 0,028 kgf/cm2 pressure on saturated mixtures were applied on the mixtures for twelve months, thus forming artificial soil samples used in the study. In order to determine the preconsolidation pressure and soil memory of each mixture, 15 undisturbed samples taken from each mold were placed in the consolidation testing apparatus and 2,86 kgf/cm2 pressure were applied to each sample for different time interval (e.g. 0, 1, 3, 6, 15 sec., etc.). These initial pressures were recorded into the memory of soil through structure (fabric). Then, we conducted standard consolidation tests in order to determine the effective pressures (preconsolidation pressures) recorded in the samples. The same procedure was applied to the other mixtures and totally 126 tests were conducted. We also determined the permeabilities of the mixtures to study the relationship between soil memory and permeability. Using the Casagrande method, the preconsolidation pressure values were determined and the results were compared to examine the effect of soil granulometry on soil memory.Doktora tezi olarak hazırlanan bu çalışmayla zemin granülometrisinin (tane da ılımının) ön konsolidasyon basıncı ve zemin hafızası üzerine etkisi incelenmi tir. Bu amaç için laboratuvarda farklı kum ve kil oranlarına sahip 10 adet karı ım hazırlanarak kalıplara alınmı , suya doygun ortamda 0,028 kgf/cm2'lik gerilme olu turacak yükler (sür aj yükü) oniki ay süreyle bekletilerek deneyde kullanılacak yapay zemin numuneleri olu turulmu tur. Hazır hale gelen herbir karı ımın ön konsolidasyon basıncını dolayısıyla hafıza özelli ini belirleyebilmek için tek bir kalıptan alınan toplam 15 adet numune ödometre deney cihazına örselenmeden yerle tirilmi ve herbir numuneye 2,86 kgf/cm2'lik gerilme olu turabilecek ön yüklemeler farklı sürelerde (0 sn, 1 sn, 3 sn, 6 sn, 15 sn, vs.,) uygulanarak olu turulan bu ön gerilmelerin doku vasıtasıyla zeminin hafızasına kaydedilmesi sa lanmı tır. Daha sonra zeminin dokusuna kaydedilen efektif gerilmeleri (ön konsolidasyon basınçlarını) belirleyebilmek için numuneler üzerinde standart konsolidasyon deneyleri yapılmı tır. Aynı i lem di er kalan karı ımlar için de ayrı ayrı tekrar edilmi ve bu amaç için toplam 126 adet deney yapılmı tır. Ayrıca permeabilite ile zemin hafızası arasındaki ili kinin varlı ını ortaya koyabilmek için karı ımların permeabilite katsayıları belirlenmi tir. Deneylerden elde edilen veriler kullanılarak Casagrande yöntemiyle numunelerin sahip oldukları ön konsolidasyon basınç değerleri hesaplanmış ve elde edilen değerlerin kar ıla tırılmasıyla zemin granülometrisinin zemin hafızası üzerindeki etkisi araştırılmıştır.Bu çalışma Ç.Ü. Bilimsel Araştırma Projeleri Birimi Tarafından Desteklenmiştir. Proje No:MMF2005D

Electrical resistivity measurements to predict abrasion resistance of rock aggregates

WOS: 000255582900014The prediction of Los Angeles (LA) abrasion loss from some indirect tests is useful for practical applications. For this purpose, LA abrasion, electrical resistivity, density and porosity tests were carried out on 27 different rock types. LA abrasion loss values were correlated with electrical resistivity and a good correlation between the two parameters was found. To see the effect of rock class on the correlation, regression analysis was repeated for igneous rocks, metamorphic rocks and sedimentary rocks, respectively. It was seen that correlation coefficients were increased for the rock classes. In addition, the data were divided into two groups according to porosity and density, respectively. After repeating regression analysis for these porosity and density groups, stronger correlations were obtained compared to the equation derived for all rocks. The validity of the derived equations was statistically tested and it was shown that all derived equations were significant. Finally, it can be said that all derived equations can alternatively be used for the estimation of LA abrasion loss from electrical resistivity

Vertical pore structure profile of a compacted clayey soil

WOS: 000327804700019An investigation was conducted to determine the vertical profile of the pore structure of a compacted clayey soil. Specimens were prepared at the dry and wet sides of optimum water content using standard compaction effort. Thin sections were prepared for microscopic analysis along vertical profiles throughout the depth of the specimens. The relative quantities of pores in the compacted specimens were determined using data obtained from image analysis of the thin sections. The parameter Pore Area Ratio (PAR) was introduced as the quotient of the area of pores to the total area for a given image to quantify pore structure. The results of the analysis indicated that PAR varied significantly from the top to the bottom of the specimens. This trend was strongest in the dry of optimum and near optimum water content specimens and less pronounced in the wet of optimum specimens, in particular under very wet conditions. The common standardized impact compaction testing procedure (i.e., standard compaction test) resulted in significant variation in the vertical pore profile of the specimens due to the cumulatively higher energy applied to the specimens near the bottom and lower energy applied to the specimens near the top. Larger and more connected pores were present in the top layers of the specimens, whereas the pores were smaller and less connected in the bottom layers of the specimens. In general, the PAR decreased with the depth of the specimens with the highest PAR observed at the top and the lowest PAR observed at the bottom of the specimens. The differences in PAR were commonly twofold to threefold between the top and bottom layers of the soils. (C) 2013 Elsevier B.V. All rights reserved.Cukurova University Research Foundation [FBE2002D47, MMF2003BAP17, MMF200043]; YOK (The Council of Higher Education of Turkey)The first step of this study was financially supported in part by the Cukurova University Research Foundation (Project Nos: FBE2002D47, MMF2003BAP17, and MMF200043). The microscopic study for the investigation was conducted at Nigde University and the analyses were completed at California Polytechnic State University. Dr. Fener was a Visiting Scholar at California Polytechnic State University in 2011-2012 with the support of YOK (The Council of Higher Education of Turkey). The first author sincerely thanks his Ph.D. supervisor Prof. Dr. Hasan Cetin, whose help and teachings in investigating the structural and textural characteristics of both artificial and natural soils, provided inspiration for his scientific studies

Evaluation of the Aşıgediği (Niğde) Quartzite for using as aggregate

Bu makale; Niğde ili sınırları içerisinde geniş bir yayılım gösteren Aşıgediği Kuvarsiti üzerinde yapılmış bir çalışmayı kapsamaktadır. Kuvarsitin beton agregası olarak kullanılabilirliğini araştırmak amacıyla bir seri analiz ve deneyler yapılmıştır. İnce kesitler üzerinde mineralojik-petrogra?k analizler yapılmış ve kimyasal analizle kuvarsitlerin bileşimleri, ayrıca kimyasal yöntemle alkali- silis reaksiyonu (ASR) belirlenmiştir. Özgül ağırlık, kuru birim hacim ağırlık, görünür porozite (gözeneklilik) gibi indeks özellikler ve tek eksenli sıkışma dayanımı, Los Angeles aşınma değeri, agrega darbe dayanımı (AIV), sodyum sülfat çözeltisindeki don kaybı gibi mekanik özellikler saptanmıştır. Analiz ve deney sonuçlarının değerlendirilmesiyle Aşıgediği Kuvarsitinin agrega olarak kullanılmasında bir sakınca olmayacağı anlaşılmıştır.This paper comprises a study carried out on Aşıgediği Quartzite covering a large area in Niğde. Numerous analysis and tests were performed on the Aşıgediği Quartzite to investigate its possible use as a concrete aggregate. Mineralogical-petrographic analyses were conducted on thin sections and chemical contents were obtained by chemical analysis. Furthermore, alkali-silica reactivity (ASR) of the quartzite was determined by chemical method. Physical properties such as specific gravity, dry unit weight, effective porosity and mechanical properties such as uniaxial compressive strength, Los Angeles abrasion value, aggregate impact value (AIV), sodium sulphate soundness were determined. Based on the data obtained from the analyses and tests, it was concluded that the Aşıgediği Quartzite can be used as concrete aggregate

Assegment of Basmakcı limestone for concrete aggregate (Niğde, Turkey)

Bu çalışmayla Niğde il sınırları içerisinde geniş bir yayılım gösteren Çamardı Formasyonunun Başmakçı Üyesini oluşturan kireçtaşlarının beton agregası olarak kullanılabilirliği araştırılmıştır. Bu amaçla Başmakçı Kireçtaşlarından alınan temsili örnekler laboratuvarda TS (1987), ISRM (1981) standartlarına göre incelenmiştir. Kireçtaşlarının; doğal birim ağırlığı 26.38 kN/m3, kuru birim ağırlığı 26.48 kN/m3, özgül ağırlığı 26.38, görünür gözenekliliği % 0.71, hacimce su emme oranı % 0.75, kütlece su emme oranı % 0.24, çekme dayanımı 8.84 MPa, nokta yük dayanımı 4.20 MPa, tek eksenli basma dayanımı 83.62 MPa, içsel sürtünme açısı 39°, kohezyonu 21 MPa, Los Angeles aşınma kaybı % 23.33 (500 devir), Schmidt çekici değeri 61, darbe dayanım katsayısı %75.66, jeokimyasal analizlere göre; sodyum sülfat çözeltisi içerisindeki donma-çözünme kaybı % 3.45, alkali silis reaksiyonu yönünden çözünmüş silis konsantrasyonu (Sc) 17.3 mmolllt, alkali azalması ise 116 mmol/lt dir. Başmakçı Kireçtaşı ilgili standartlara göre değerlendirildiğinde beton agregası olarak kullanılabilir nitelikte olduğu sonucuna varılmıştır.In this study, we have tried to investigate the usability of limestons from the BaşmakÇı Limestone member of Çamardı Formation, which widely crop out in the vicinity of Niğde, as concrete aggregate. For this reason, BaşmakÇı limestone samples that were collected in the field were examined according to TS (1987) and ISRM (1981) standards. Some index properties that were found as a result of the laboratory studies were: natural unit weight: 26.38 kN/m3, dry unit weight: 26.48 kN/cm3, specific gravities: 26.38, apparent porosity: 0.71 %, water suction ratio (volumetrically): 0.75 %, water suction ratio (weight): 0.24 %, indirect tensional strength: 8.84 MPa, point load index: 4.20 MPa, uniaxial compressive strength: 83.62 MPa, internal friction angle: 39°, cohesion: 21 MPa, Los Angeles abrasion loss: 23.33 % (500 cycle), Schmidt hammer value: 61, coefficient of compact strength: 75.66 %. According to geochemical analyses; freeze loss in sodium sulphate: 3.45 %, silis concentration in the alkali silis reaction (Sc): 17.3 mmolllt, decrease of alkali: 116 mmol/lt were found. It was found that the BaşmakÇı limestone is suitable for the concrete aggregate usage

Prediction of artificial soil's unconfined compression strength test using statistical analyses and artificial neural networks

WOS: 000281499100006Laboratory prediction of the unconfined compression strength (UCS) of cohesive soils is important to determine the shear strength properties. However, this study presents the application of different methods simple-multiple analysis and artificial neural networks for the prediction of the UCS from basic soil properties. Regression analysis and artificial neural networks prediction indicated that there exist acceptable correlations between soil properties and unconfined compression strength. Besides, artificial neural networks showed a higher performance than traditional statistical models for predicting UCS. Regression analysis and artificial neural network prediction indicated strong correlations (R(2) = 0.71-0.97) between basic soil properties and UCS. It has been shown that the correlation equations obtained by regression analyses are found to be reliable in practical situations. (C) 2010 Elsevier Ltd. All rights reserved.Nigde University Research Foundation [FEB 2009/23]This study was financially supported in part by the Nigde University Research Foundation (Project No: FEB 2009/23)

Evaluation of Niğde Sineksizyayla Metagabbro as concrete aggregate

Bu makale Niğde ili sınırları içerisinde geniş bir yaydım gösteren Sineksizyayla Metagabrosu üzerinde yapılmış bir çalışmayı kapsamaktadır. Bu metagabronun agrega olarak kullanılabilirliğini araştırmak amacıyla bir seri analiz ve test yapılmıştır. İnce kesitler üzerinde mineralojiktpetrografik analiz yapılmış ve kimyasal analiz ile bileşimleri belirlenmiştir. Kuru birim hacim ağırlık, özgül ağırlık, görünür porozite, su emme gibi fiziksel özellikler ve tek eksenli sıkışma dayanımı, agrega darbe dayanımı (AIV), Los Angeles aşınma kaybı, sodyum sülfat çözeltisindeki don kaybı gibi mekanik özellikler tespit edilmiştir. Analiz ve test sonuçlarının değerlendirilmesiyle Sineksizyayla Metagabrosunun alkali reaktivitesi düşük çimentolarla kullanılması durumunda beton agregası olarak kullanılmasında bir sakınca olmayacağı anlaşılmıştır.This paper describes a study carried out on Sineksizyayla Metagabbro spreading In Niğde Area. Numerous analyses and tests were performed on Sineksizyayla Metagabbro to investigate the possibility of using it as aggregate. Mineralogical-petrographical analysis were conducted on thin sections and chemical compositions was obtained, by chemical analysis. Physical properties such as dry unit weight, specific gravity, effective porosity, water absorption and mechanical properties such as uniaxial compressive strength, aggregate impact value (AIV), Los Angeles abrasion value, sodium sulphate soundness were determined. According to the results of the analyses and the tests were evaluated, it was concluded that Sineksizyayla Metagabbro can be used as concrete aggregate by cement that has low alcali reactitivy

A hydrogelogical study on Horata (Malatya) karstic spring

İnceleme alanı Malatya il merkezinin güneyinde yer almaktadır. İnceleme alanı Paleozoyik, Mesozoyik ve Senozoyik yaşlı birimlerden oluşmaktadır. Bunlar Malatya Metamorfitleri, Gündüzbey Formasyonu, Yeşilyurt Formasyonu, Taraça ve Alüvyondur. Horata Karstik Kaynağı'nda uzun süreli debi değişimi ve iyon değişimi kontrol edilmiştir. ...The study area is located to the in south of city of Malatya. Paleozoic, Mesozoic and Senozoic aged formations crop out in the study area. These are Malatya Metamorphics, Gündüzbey Formation, Yeşilyurt Formation, Debris and Alluvial. Long-term measurements of discharge and ion contents were carried out in Horata Karstic Spring. ..

Performance prediction of roadheaders used in coal mines from the needle penetration index and the schmidt hammer value

Abstract Coal mine galleries and construction tunnels are commonly excavated using roadheaders. Estimating the performance of roadheaders is crucial for planning and cost estimation when planning tunnel or tunnel projects. The aim of this study is to derive generalized performance prediction models including Schmidt hammer value, needle penetration index, and volumetric joint count for roadheaders used in coal mines. The performance measurements of axial and transverse type roadheaders were carried out in six different coal mines. Schmidt hammer tests, needle penetration index tests, and of volumetric joint count measurements were also performed at the locations where the performance measurements were conducted. The extensive data were evaluated using multiple linear and nonlinear regression analysis. The developed formulas were evaluated using statistical tests. The Equations that include the Schmidt hammer value or needle penetration index value in addition to cutter head power have been shown to be unreliable. However, the equations that include Schmidt hammer value or needle penetration index value in addition to cutterhead power and volumetric joint count have been shown to be reliable. This study concludes that the developed reliable equations can be used for the performance assessment of roadheaders used in coal mines

The effect of grain size distribution on compaction and shrinkage properties of clays

Bu çalışmada, killi zeminlerde tane boyu dağılımının kompaksiyon üzerindeki etkisi ve sıkıştırılmış killi zeminlerin büzülmesi araştırılmıştır. Bu amaçla indeks özellikleri birbirine yakın, farklı mühendislik davranışlarına sahip Handere kili (smektit) ile Almanpınarı kili (illit) içerisine farklı oranlarda tek biçimli silis kumu karıştırılarak, yapay zemin örnekleri hazırlanmıştır. Hazırlanan zemin örnekleri ile standart Proktor kompaksiyon deneyleri yapılarak optimum su içeriği ve en büyük kuru birim hacim ağırlık değerleri arasında ilişkiler araştırılmıştır. Araştırmada kullanılan her iki kil örneğinde kum oranındaki artışa bağlı olarak, standart kompaksiyon deneylerinde en büyük kuru birim hacmin arttığı, optimum su içeriklerinin azaldığı ve buna bağlı olarak büzülmelerin azaldığı gra?kler çizilerek gösterilmiştir. Deneylerden elde edilen kompaksiyon parametreleri ve büzülme değerleri kullanılarak regresyon analizleri gerçekleştirilmiştir. Eğri uydurma teknikleri kullanılarak ilişkiler elde edilmiş, regresyon doğruları çizilmiş ve görgül denklemler türetilmiştir.In this study, the influence of grain size distribution on the compaction and the shrinkage of compacted clayey soils were investigated. For this aim, artificial soil samples were prepared by way of adding uniform silica sand into Handere clay (smectite) and Almanpınarı clay (illite) with similar index properties, but different engineering behaviors. Mutual correlations of each optimum moisture content and maximum dry density of the soil samples were investigated by employing standard proctor tests on soil samples prepared. It was put forwarded with the assistance of graphical analyses that maximum dry densities were increased and optimum moisture contents were decreased when sand proportions were increased on standard compaction tests, and thus shrinkage were decreased. Regression analyses were carried out using the compaction parameters and shrinkage values obtained from the experimental studies. Correlations were obtained using curve fitting techniques, regression curves were drawn, and empirical regression equations were derived