7337

6840

كارشناسي ارشد

مكانيك سنگ

اصفهان: دانشگاه صنعتي اصفهان، دانشكده معدن

1391

93ص.: مصور، جدول، نمودار

ص.ع. به فارسي و انگليسي

عليرضا باغباني، حميد هاشم الحسيني

علي احمد عاملي

11/9/91

مهدي ابطحي، مسعود چراغي

1396/09/21

كتابنامه

معدن

مهندسي معدن

ID6840

به فارسي و انگليسي: قابل رويت در نسخه ديجيتالي

93 Investigation of Biogrout s Properties at a Laboratory Scale Issa Aghayari i aghayari@gmail com Date of Submission 2012 09 Department of Mining Engineering Isfahan University of Technology Isfahan 84156 83111 Iran Degree M Sc Language FarsiSupervisor Alireza Baghbanan bagh110@cc iut ac irSupervisor Hamid Hashemolhoseini hamidh@cc iut ac irAbstractThe use of microbiologically induced calcite cementation for ground improvement presents a newand innovative ground improvement technique for geotechnical engineers This method may haveprovide a very effective way for improvementation of soils and prevent liquefaction induceddamage This technique uses non pathogenic micro organisms which are found naturally in a soilstructure and could make a cementation base for sand particles This method does not have someharmful environmental impacts which may occur when conventional ground improwmenttechniques such cement grouing or chemical grouting are used This study presents the results ofan experimental research that was conducted to investigate the effect of microbiologicalproperties induced calcite cementation in sands In order to determine the optimum conditions forcalcite precipitation at laboratory when a soil microorganism called Sporosarcina Pasteurii PTCC 1645 is injected into a soil structure firstly an systematic laboratory experiments wasconducted in liquid phase using some experiment design methods In this study the values of urea calcium cloride concentration pH temperature and percent of bacteria was considered asexperiment variables and the results was statistically analysed to find the optimum conditions Itwas shown that the best reaction of bacteria is presented when 0 5 mol of urea and calcium clorideconcentration and 9 of bacteria are mixed at 7 9 value of pH in 25 degree temperature Underoptimum condition Bio treatment of the sand was performed using Sporosarcina Pasteurii PTCC 1645 A uniform graded sand was selected as a soil type for this study Soil samples wascompacted in cylindrically shaped pvc columns with 5 cm diameter and 11 cm height to achieveda density of 1 60 gr cm3 and the grouting procedure was initialized Then the bacterial suspensionwas injected and after 24 hours cementation solution at constant pressure was added Thetreatment procedure was repeated three to four times for five houres to achive a maximumprecipitation of calcite After cementation the specimens were dried at 70 in a oven In order toinvestigate the grouting effects on the soil the treated specimens were subjected to differentmechanical tests such as unconfined compression test on dry samples permeability test on wetsamples determination of compression pulse velocity for dry samples and unconsolidated undrained triaxial compression tests after 3 7 14 and 28 days The maximum uniaxialcompressive strength was 680KPa at the 28 days and the cohesive and friction angle wasdetermined 110KPa and 41 degree respectivelly The calculated permeability was also decreasedalmost one order compared with a not treated sand Keywords ground improvement biogrouting Sporosarcina Pasteurii unconfined compression permeability test optimum condition

عليرضا باغباني، حميد هاشم الحسيني

علي احمد عاملي

مهدي ابطحي، مسعود چراغي