İ.T.Ü. kampüs alanındaki kayaçların yüzey pürüzlülüğünün görüntü analiz yöntemi ile araştırılması /
Yazar: ERKAN BOZKURTOĞLU
Danışman: PROF.DR. MAHİR VARDAR
İstanbul Teknik Üniversitesi / Fen Bilimleri Enstitüsü / Uygulamalı Jeoloji Ana Bilim Dalı
Derece: Yüksek Lisans, 1996
Konu: Jeoloji Mühendisliği = Geological Engineering
Dizin: Görüntü analizi = Image analysis ; Kayaçlar = Rocks ; Yerleşke = Campus ; Yüzey pürüzlülüğü = Surface roughness ; İstanbul Teknik Üniversitesi = Istanbul Technical University

Özet:
ÖZET Yüksek Lisans tezi olarak hazırlanan bu çalışmada ÎTÜ Kampus alanının jeoloji ve mühendislik jeolojisi çalışması yapılarak; bir yüzeye ait kalıp üzerinden alman video kamera görüntülerin mühendislik jeolojisi mantığı ile işlenmesi sonucu elde edilen neticelerin sonuçlan sunulmuştur. Çalışma, başlıca iki kısımdan oluşmuştur. Birinci kısım jeoloji ve mühendislik jeolojisini içermekte olup, inceleme alanında yüzeylenen litolojik birimlerin yapısal ve mühendislik özelliklerinin saptanmasına yöneliktir. Bu amaç çerçevesinde 1/2000 ölçekli mühendislik jeolojisi haritası yapılmış, aynı ölçekte jeolojik kesitler alınmıştır. İTÜ göleti gövde kesiminde yapılan sondajlardan yararlanarak çizilen 1/500 ölçekli jeolojik kesit ile dolusavağın 1/100 ölçekli açılımı mühendislik jeolojisi bölümünde sunulmuştur. Çalışmada ayrıca, kampus sahasında geniş bir yayılım sunan fliş karakterindeki Trakya formasyonuna ait kumtaşı, silttaşı ve çamurtaşı fasiyesi erinin yayılım sunduğu sınırlar ayırtlanmaya çalışılmış ve kampus alanında gözlenen kayaçlann 1/10000 ölçekli ayrışma derecelerini içeren bir haritası yapılmıştır. Çalışmanın ikinci kısmında, genel grup ismi olan lateks olarak bilinen ve polimer bazlı bir sıvı olan polibütadiyen kullanılarak bir kaya yüzeyinden nasıl kalıp alınacağı, laboratuvar ortamında yüzeyi temsil edecek şekilde yeni bir kalıbın içine nasıl yerleştirileceği anlatılmış ve özel amaçlı yüzey çalışmaları için gerekli olan yüzey miktarının, maksimum ve minimum sınırlarının tespiti için yöntem önerilmiştir. Çalışmanın son bölümünde, araştırmanın bütününden elde edilen sonuçlar sunulmuştur. XII

Abstract:
SUMMARY THE INVESTIGATION OF JOINT SURFACE ROUGHNESS ON THE ROCKS IN ITU CAMPUS AREA BY IMAGE PROCESSING METHOD One of the aims in geotechnical studies considering media, technical attempt and media effects is to determine the mechanical parameters of media and to investigate their suitability to technical attempt. At and after the stage of technical attempt effects of new added loading conditions can be correctly determined by detailed geologic and engineering geologic studies. In this study, the media properties of ITU Maslak campus was investigated at the influence of media, technical attempt end environment. Engineering Geology and weathering map of the study area was made. Carboniferous age Trakya formation (fly ash sedimentation) widely spreading in Istanbul and forming the large part of the investigation area was differentiated according to the boundaries of sandstone- siltstone and mudstone facies and each unit was examined in detail. These units were mapped by differentiating as much as a scale of 1/2000 allows since siltstone- sandstone sequence in Trakya formation changes very often, siltstone outcrops in sandstone areas and sandstone outcrops in siltstone areas in the map may be seen in the field. Because of different deformation properties at sandstone and siltstone levels of Trakya formation, this unit was intensely jointed under stresses. By existing milonitic zones that are characteristic future of fault planes, these frequently observed local fractures on outcrop surfaces are easily determined. Joint frequency in the unit having intensely developed systematically and random joints, varies and may be about lcm./m. around large fault zones. As a result of the evaluation of joint measurement, it is determined that average joint frequency in this unit is about 15 cm. measured dip end strike values of bedding planes are intensely variable. Dip and strike values of bedding planes in polar coordinate system are given in Figure 1 below. As seen in figure, dominating strike is in NW direction and dominating dip direction changes between NE and SW. Permeability of the formation was found as 10"5-10"7 cm./s. by Lugeon tests conducted at drillholes for preconstruction investigations of ITU small dam. According to these values in this highly impermeable unit, permeability of rock in reservoir area may increase due to weathering. Around the reservoir area this unit Xlllstrikes in NW direction and dips SW. Bedding thickness observed in this unit changes between 3 and 1 00 cm. Dip direction ? ? ??* ?.?? ? ? 80 t ?60," ? 4» :*#**$#* +J* * ? T t.? ? £ ? ? I 100 ?%> ? ? Figure 1. Relationship between strike and dip direction of bedding planes in Trakya formation. Anticlinoriums and senclinoriums are frequently observed in bedding planes, sandstones are medium and thick, siltstones are medium and thin and mudstones are laminated longitudinal joints developed in this unit strike N23-85W, and dip 27-89 SW and transverse joints strike N13-72E and dip 36-89 SE, joints frequency changes between 0,8 and 1 mm. and generally there is no gouge in joints. Joints are locally field by own material, quartz and FeO. In this investigation done for geotechnical purpose, as a result of geologic and engineering geology studies, type, quantity and number of laboratory tests necessary for this media and technical attempt are known, but in studies for special purposes such as shear strength of a rough surface, suitability for injection, etc. it is undetermined how maximum and minimum working values, belong and completely representing this surface are not defined. This study is an attempt to solve this problem. A cast of rough surface was formed and surface was evaluated by image analysis techniques. Obtained values were statistically analyzed. As a result of this, a new method is offered to determine the maximum and minimum size of a surface which is subject to special examination for a satisfactory outcome. In this method, the aim is to measure the length of shadow formed by asperities of the surface under specific light direction. Areal roughness obtained in this unit of glosness give a heterogeneity as depending on the size of surface and asymmetry of XIVasperities but by dividing the heterogeneous areal roughness in to subareas, an homogeneous subarea will be obtained as depending on surface properties. Statistical analysis of glosness values of this homogeneous area gives maximum and minimum boundary values representing the surface. Image analysis program gives a numerical values between 0 and 256 according to tones of gray. Zero means the darkest and 256 means the lightest. In order to determine the surface glossiness values images of the surface must be transferred to computer. In this stage reflecting light from the surface under directed light forms the images. When the image analysis program is used to determine the degree of polishing on a marble surface, due to smoothness of the marble surface and reflecting light in specific angle, any light source can be used. On the other hand, in order to avoid dispersion of light on the rough surface parallel light source must be used. Because of this relationship between the light and rough surface analyzing in-situ taken image on the field will be worry. Due to this difficulties it is clearly fact that taken a mold of a rock surface from field is necessary. So we tried some molding material in laboratory from granular to liquid and decided to use polybutadien which is known with latex at the marketing. As known as to be plant milk the latex is a liquid of euphorbium, lettuce and such of other plants in the milk vein. It is a plazma has a lot of nucleous and exhibit a riches with starch, diastas, alcoholloid and hydrocarbon. The composition of latex as like as milk and only to be stable when it is light alcaline. When the latex is replaced on a surface in wheather it's nucleous become together and change to flexible stiffness material. To take a mold of some surface using this material including some steps which are given by order at the following row. - Firstly choose a surface is been the aim of necessary to study. - Wash the surface and wait to dry. - Applied the liquid to the surface with a brush. - Wait the liquid will dry with air and wash the brush with solvent for the prevent to dry luquid at the brush hair. - After the liquid dry repeat this action 2 or 3 times again - When the last layer was drying put the thread to the surface and spread it with hand to take all form of the surface. - Pour the liquid on thread largely and spread it with hand. - Put the other thread on the first it and spread with hand, then pour luquid again and spread. - Repeat this action 4 or 5 times. - Never pour liquid on the last thread. - Wait the liquid will dry in the thread pore. XV- Pull the liquid with thread from the surface. After all this process you can move the surface mold without any problem where you want and how you want. The reason of using thread with liquid is to protect all the details wave and roughness of the surface due to the speciality of flexible of liquid. The thread is taken the surface wave when the liquid become hard in its pore. The surface roughness is protected with hardening of liquid. At the laboratoary the liquid mold replace in a MDF wool mold with plasters of Paris. The thread side of this mold put on the plaster to be a corner of latex liquid would be 0 (zero) plane In this study taken a 200x8cm. dimension latex mold would be necessary to search the maximum and minimum portion of the investigated surface would be adequate for detail study. After the surface image had been taken to the computer with a video camera and appreciated with image process program, all the main files of surface image would started to divide in order beginning from 2 to 1 6 respectively and had an new color image number for every new image file. If we emphasize these divided image files more clearly, we will have new image files belong to every one main image and have a new numerical value of these. In the following line the exhibeted numbers are belong to only one main file with its diveded in range as 2, 4, 8, 16 and shows how much numerical values the surface has at this subdiveded files. For 40 main files (1 - No diveded) " 80 " " (2 - diveded 2 every main files) " 160 " " (4- " 4 " " " ) " 320 " " (8- " 8 " " " ) " 640 " " (16- " 16 " " " ) We took all main image files (40 files) 2 times giving the paralel light beam from the different side due to the symmetry or asymmetry of surface and had compare the 80 main files image drawing to the image value. Figure. 2 shows the g files and Fig. 3 shows the gk files according to the giving light to the surface its right and left side. According to the this figures there is an asymmetry on the surface roughness. XVIFigure 2 : The imagining roughness prophile of the surface with the g files value, Fig 3 : The imagining roughness prophile of the surface with the gk files value The relationship between the all files and their numerical image value is given in fig 4 and 5 for g and gk images. According to the fig 4 and 5 it is inessential to dive the every one image file more than 16 part. And we tried to search the maximum and minimum portion of this surface using the acquisition of this subdivided image's numerical value. So we made an statistics research and had an inference about what we want and propose a method to define what percent of a surface must be necessary to investigate for detail study. At the end of this study we find a maximum and minimum value for Trakya formation's rock surface is 24 % and 1 7.2 %. xvuFig 4 : The relationship between all g image files and their numerical value. Fig 5 :The relationship between all gk image files and their numerical value xvin