شماره راهنما :
1171 دكتري
پديد آورنده :
داربر، محمد
عنوان :
تأثير ناهمسانگردي بر خواص مكانيكي، نرخ نفوذ و انرژي مخصوص حفاري سنگها
گرايش تحصيلي :
مكانيك سنگ
محل تحصيل :
اصفهان: دانشگاه صنعتي اصفهان، دانشكده معدن
صفحه شمار :
ص، [۱۸۶]ص.: مصور، جدول، نمودار
استاد راهنما :
لهراسب فرامرزي
توصيفگر ها :
ناهمسانگردي , دانه بندي , ابعاد نمونه , رگرسيون چندگانه غير خطي , شبكه هاي عصبي مصنوعي پرسپترون , مدلسازي فيزيكي , خصوصيات ژئومكانيكي , انرژي مخصوص تخريبي , تردي , انرژي مخصوص حفاري , نرخ نفوذ حفاري چرخشي
استاد داور :
ممتحن داخلي: راحب باقرپور; ممتحن خارجي: پرويز معارف وند، ممتحن خارجي: كامران گشتاسبي
تاريخ ورود اطلاعات :
1397/01/29
كد ايرانداك :
ID1171 دكتري
چكيده فارسي :
چكيده RQDMATLAB cm cm cm RQD كلمات كليدي
چكيده انگليسي :
AbstractThe mechanical properties specific energy and drilling performance of the rocks areinfluenced by the anisotropy The anisotropy of the rocks is due to the discontinuity or dueto variations in the size shape and position of mineral grains Prediction of specific energyand rate of penetration of rotary drilling is an essential step in designing drilling projects andevaluating the time and drilling performance The present study can be classified into threekey sections In each of these sections the effect of discontinuity diameter and grain size onmechanical properties specific energy and rate of penetration of coring drilling have beeninvestigated In the first section of this thesis the specimen size effect on uniaxial compressive strengthof 114 rock samples and 84 concrete specimens using specimen size effect models has beeninvestigated The results of this section indicated that the prediction of specimen size effectmodels depends on the preparation and anisotropy of the specimens In the igneous rocks outputs of the multi fractal scaling model and the specimen size effect model using thefracture energy theory and in the sedimentary rocks results of the specimen size effect modelusing the fracture energy theory exhibited a better correlation with the results of previouslaboratory tests Also in the concrete specimens in the small diameters results of Hoek andBrown model and in the large diameters outputs of the multi fractal scaling model indicateda better correlation with the results of previous laboratory tests The results of this sectioncan be utilized to design engineering projects at different scales such as repositories ofstoring oil and gas underground power plants and radioactive waste repositories In the second section the effect of anisotropy on penetration rate of 91 m coring drillingconducted in state of Wyoming has been studied Also a combination of two techniques ofnon linear statistical and artificial neural networks was used to estimate coring drillingperformance The results of non linear statistical analysis exhibited that the four parametersof brittleness RQD humidity and anisotropy index have better correlation with the rate ofdrilling penetration However the values of the determination coefficient of the non linearstatistical models were low For this reason non linear statistical models were developedusing multi layer perceptron neural network technique by MATLAB software The resultsof this section show that the neural network is a useful tool to minimize uncertaintiesencountered during drilling process In the third section using physical modelling and statistical methods the effect of the grainsize the discontinuity angle and also the effect of the sample diameter on the mechanicalproperties rate of penetration and the drilling specific energy was studied Also novelmodels were proposed to predict the performance and drilling specific energy In order todirectly measure of the drilling specific energy the laboratory automatic coring machine wasdesigned and manufactured to determine the instantaneous and average trust on the drillingbit and the drilling specific energy In this section using physical modelling 10 concreteblocks with dimensions of 50 cm 50 cm 50 cm with three angles of 30 45 and 60degrees and three grain sizes 0 9 5 mm 0 12 5 mm and 0 19 mm were manufactured Concrete blocks with three diameters of 52 76 and 102 mm and with length of 50 cm weredrilled using laboratory automatic coring machine The results of 86 m drilling 172 coresand 688 prepared specimens and 124 servo control uniaxial compressive tests showed that by increasing the angle of discontinuity from 30 to 60 degrees the trust on the bit and drillingspecific energy increase and rate of drilling penetration the uniaxial compressive strengthand the elastic modulus decrease Also in the low diameters of drilling the specific energy
استاد راهنما :
لهراسب فرامرزي
استاد داور :
ممتحن داخلي: راحب باقرپور; ممتحن خارجي: پرويز معارف وند، ممتحن خارجي: كامران گشتاسبي
