Loading...
Search for:
saghandali--fardin
0.123 seconds
Investigating the Behavior of the Group Energy Pile in Unsaturated Silty Sand Soil Using Physical Modelling
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
A physical model has been developed in the advanced soil mechanic lab of the sharif university of technology. This model has been used to investigate the thermo-hydro-mechanical behavior of the group energy pile, which was embedded in the unsaturated silty sand soil. This model contains a steel soil box, 4 aluminum piles, strain gauges, the total pressure cells, the thermocouples, and the mechanical load. Three sets of tests were conducted on these piles. In the first the thermal cycles were applied on 1 pile and in the second and third tests, the number of the energy piles was 2 and 3, respectively. The result has shown there was a permanent settlement at the end of the thermal cycles....
Hydrogel nanocomposite network elasticity parameters as a function of swelling ratio: from micro to macro flooding
, Article Journal of Industrial and Engineering Chemistry ; Volume 125 , 2023 , Pages 163-177 ; 1226086X (ISSN) ; Baghban Salehi, M ; Taghikhani, V ; Sharif University of Technology
Korean Society of Industrial Engineering Chemistry
2023
Abstract
Gel flooding is one of the most important cEOR methods. In this study, a Co[AM-AMPS-MA-AAC]/PEI-MBA nanocomposite, using zirconium or zinc nanoparticles, was synthesized to improve the performance of traditional hydrogels. FTIR and XRD tests confirmed the three-dimensional structure and homogeneous distribution of nanoparticles. The SEM and ESEM images revealed a homogeneous and 3D structure with an average pore size of 35 nm. The sweep strain test showed that the maximum storage moduli of Zr and Zn nanocomposites are 21,300 and 7700 Pa, respectively. The frequency sweep test showed linear viscoelastic behavior at various frequencies. According to TGA results, less than 1% of the...
Design and fabrication of a preformed thixotropic-viscoelastic nanocomposite hydrogel system (PNCH) for controlling sand production in reservoirs
, Article Results in Engineering ; Volume 18 , 2023 ; 25901230 (ISSN) ; Baghban Salehi, M ; Taghikhani, V ; Sharif University of Technology
Elsevier B.V
2023
Abstract
In this study, the performance of preformed dual crosslinked nanocomposite hydrogels (PNCH) consisting of acrylamide, 2-acrylamide-2-methylpropane sulfonic acid, maleic acid, and acrylic acid in sand control was investigated. Also, the effects of three nanoparticles (NPs) of iron (PNCH1), silicon (PNCH2), and bentonite (PNCH3) on the PNCH structure were studied. The morphology, equilibrium swelling ratio (ESR), rheology, thermal strength, zeta potential, and compressive strength were experimentally analyzed. According to the XRD results, the NPs were completely dispersed in all three samples. The results of SEM and EDS tests confirmed the presence of NPs within the PNCHs with a dense,...
Improved oil recovery by 3D hydrogel composite reinforced with natural bentonite nanoparticles
, Article Iranian Polymer Journal (English Edition) ; Volume 32, Issue 11 , 2023 , Pages 1393-1404 ; 10261265 (ISSN) ; Baghban Salehi, M ; Taghikhani, V ; Sharif University of Technology
Springer Science and Business Media Deutschland GmbH
2023
Abstract
Over the past years, oil and gas research works have been concentrated in the enhanced oil recovery methods through injection of chemical materials. In this work, Co[AM-AMPS-MA]/PEI-MBA(Ben) nanocomposite hydrogel was designed and synthesized. To characterize the synthesized nanocomposite hydrogel, TGA, DTG, XRD, FTIR, SEM, and ESEM techniques, and equilibrium swelling, frequency and temperature sweep, and micromodel tests were applied. Based on TGA and DTG data, thermal stability of the sample was confirmed at the reservoir temperature. The XRD analysis confirmed the amorphous structure of the nanocomposite hydrogel and the homogeneous distribution of the nanoparticles in its structure. SEM...
Synthesis of Heteropolyacid Catalysts Stabilized on Clay for Conversion of Carbohyderates into 5-Hydroxymethylfurfural
, M.Sc. Thesis Sharif University of Technology ; Kazemeini, Mohammad (Supervisor) ; Sadjadi, Samaheh (Supervisor)
Abstract
Three Keggin-type heteropolyacids were impregnated upon halloysite to produce heterogeneous acidic catalysts for synthesizing 5-hydroxymethylfurfural (5-HMF). Comparing the effectiveness of variously prepared catalysts in producing 5-HMF from fructose revealed the important role of halloysite in the final catalyst's acidic properties and performance in the reaction of halloysite-supported silicotungstic acid. Adjusting the reaction parameters for obtaining optimal results for the catalyst of choice was conducted via Response Surface Methodology and it was found that use of catalyst with 11 wt.% active ingredient at 125 °C in DMSO solvent yielded the target compound with 99.5% after 43 min....
Nanofluid preparation, stability and performance for CO2 absorption and desorption enhancement: A review
, Article Journal of Environmental Management ; Volume 313 , 2022 ; 03014797 (ISSN) ; Rahimi, K ; Saghandali, F ; Scott, J ; Lovell, E ; Sharif University of Technology
Academic Press
2022
Abstract
In recent years, the importance of capturing CO2 has increased due to the necessity of minimizing climate change and the detrimental effects of CO2 emissions from industrial processes. CO2 absorption, as one of the most mature carbon capture technologies, has been improved by introducing nanosized particles into liquid absorbents. Nanofluids have been the subject of interest in many studies recently due to their tremendous impact on absorption. This review comprehensively examines the CO2 absorption behavior for nanofluids through the investigation of different absorption systems. Potential mechanisms for improving the absorption/regeneration performance of nanoabsorbents as well as the...
Dynamic Parameters of Saturated and Unsaturated Sand at Different Range of Shear Strain Levels in Cyclic Simple Shear Test
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
In this investigation, a series of cyclic simple shear tests were carried out in order to evaluate dynamic parameters of Babolsar and Toyoura sand at levels of saturation 25, 50, 75 and 100%. 96 tests were conducted using SGI type cyclic simple shear device. The specimens were cylindrical, with 7cm diameter and 2.2 cm height. The tests were performed under both drained condition (constant-load) at levels of saturation 25, 50%, and undrained condition at levels of saturation 75, 100%. All tests were performed under vertical consolidation stress of 50 and 150 kPa, relative density of 30 and 70% and cyclic shear strain of 0.5, 5 and 10%. The tests were shear strain-controlled with an...
Investigation of Dynamic Response of Shallow Foundations on Sandy Soil to Horizontal Harmonic Loading by Physical Model Tests
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
The most important step in current dynamic analysis of machine foundations is determining dynamic impedance functions. Impedance functions are defined as ratios of applied force or moment to induced displacement or rotation angle of foundation. In this research, horizontal dynamic response of foundation on homogeneous halfspace was investigated using physical modeling. Soil medium was built in a 1mx1mx0.8m steel box whose interior walls were covered by 0.1m of sawdust (a material with high damping). In order to prevent possible reflection of waves, this cover was extended to the box bottom with 0.2 m thickness. Sand raining method was used to build soil medium. In this method, with...
Investigation of Dynamic Response of Shallow Foundations on Layered Soils to Horizontal Harmonic Loading by Physical Model Tests
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Increasing requirements of industries and research institutes to analytical results of interaction soil-foundation related systems, reveals the importance of the dynamic impedance functions than ever before. The dynamic impedance function relations are presented for massless rigid foundations which is possible to obtain dynamic response of foundations for different frequencies and masses accordingly. In this study, the dynamic impedance functions were investigated using physical modeling tests on sandy soil with finite thickness soil stratum over bedrock. The tests were carried out inside a steel container of dimensions 110.8m in length, width and height respectively which was filled into...
Survey the Change of Phreatic Line Position in the First Filling of Earth Dams until Steady State Seepage
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Since seepage-related problems account for the cause of more than forty percent of dam failure seepage analysis serves as one of the most significant stage in the design process of an embankment dam. Currently a steady seepage analysis in a typical or maximum cross section of the dam is formed instead of transient seepage analysis for simplicity. In this way, for the change of condition (unsaturated to saturated) in the first filling of dams and it’s effects on behavior and reaction of dams until the steady seepage condition established; the results of steady seepage analysis cannot be satisfactory. In this thesis, based on finite element method and with assumption of saturated-unsaturated...
Investigation of Dynamic Response of Shallow Foundations on Layered Soil Medium by Physical Modeling
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Dynamic impedance functions method is most recent approach in the analysis of soil-foundation dynamic interaction, and presented for massless rigid foundations. Impedance functions are frequency dependent functions, and used to obtain dynamic response of foundation with arbitrary mass subjected to dynamic loading of any frequency and magnitude. The important assumptions for appropriate useof mentioned method are rigidity of foundation and visco-elastic behavior of the soil beneath the foundation. In this study, experimental vertical impedance functions of square and circular foundations have been investigated,using physical modeling tests. A granular soil layer with finite thickness...
Comparison of Slopes' Pgds Derived From Newmark Rigid Block Theory With 1g Shaking Table Model Tests
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Moderate to large magnitude earthquakes trigger hundreds to thousands of slope stability failures and landslides in coherent masses. In many earthquakes, landslides have been responsible for as much or more damage than all other seismic hazards combined. Earthquake-induced landslides have a detrimental impact on the serviceability of slopes by damaging nearby structures, roadways, utilities, power lines and communication networks. In this research large-scale shaking table model tests were conducted to study slope behavior under earthquake conditions on Sharif University shaking table. The model slopes were installed into a model box with a length of 3 m, width of 1 m, and height of 1.5 m. A...
Evaluation of Dynamic Properties of Plastic Concrete Using Bending Disk Tests in Small Strain Range
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Evaluation of the compression wave velocity (Vp ) and small strains elastic modulii of various types of plastic concrete specimens in unconfined and triaxial compression tests using piezoelectric transducers was performed in this study. Plastic concrete consists of aggregates, cement, water and bentonite, mixed at a high water cement ratio, to produce a ductile material. It is used for creating an impermeable cut-off wall for seepage control in highly permeable dam foundations. A plastic concrete cut-off wall acts essentially as a barrier to stop or reduce the groundwater flow. In this study the effect of specimen age, water-cement ratio, bentonite-cement ratio, confining pressure, wave...
Evaluation of Strength Parameters of Plastic Concrete by Triaxial Tests
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
This research are divided into the two main parts. In the first part, effective parameters for prediction of 28 days strength of plastic concrete have been determined. In this part, data mining operation was done on some informations which was sent from Silveh Dam construction site. In dam construction site, for quality control of plastic concrete which used in building of cut off wall some tests are done regurlarly in 7 and 28 days of concrecte production. In first part we used artificial neural network for predicting of relation between 28 days strength parameter and varios parameters of dam mixture content. The results has shown that the most effective parametes on 28 days strength...
Investigation of Dynamic Response of Buried Pipelines under Earthquake-Induced Landslide using Physical Model Tests
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
The purpose of this dissertation is investigation of dynamic behavior of buried pipelines in slopes in landslide. For this purpose four physical models were made on shaking table of Sharif University of Technology. In each of the models some pipes were buried in slope. In these models the pipes were placed in different angles regarding to slope direction. Simulation laws suggested by Iai (1989) were used in these models. Babolsar sand was used for modeling the slopes. Aluminium pipes with outside diameter of 16 millimeters and thickness of 1 millimeter were implemented to model steel pipelines. In this investigation simple supports were used at the end of the pipes, considering the...
Evaluating the Usage of Polystyrene Protection Behind the Buried Pipelines on Dynamic Response of Soil Slope with using a 1g Shaking Table
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Studying of slope stability under dynamic loading such as earthquakes is one of the critical issues. This importance is attributed to many of the slopes are located in urban areas, either around them or in the important buildings and infrastructure. Thus, evaluation of slope’s behavior is very essential. On the other hand, preparing fundamental arrangements to improve the current situation, surrounding and buried areas in the slope is necessary.
In this study, a physical model of Tehran's slopes by 0.1 ratio with pipes that have been retrofitted by plastofoam developed. This model was tested on the shaking table under dynamic loading. The dimensions of the slope were 1 meter width, 3...
In this study, a physical model of Tehran's slopes by 0.1 ratio with pipes that have been retrofitted by plastofoam developed. This model was tested on the shaking table under dynamic loading. The dimensions of the slope were 1 meter width, 3...
Investigation of Dynamic Response of Foundations on Sandy Soils to Two-Way Horizontal Harmonic Loading by Physical Model Tests
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Increasing requirements of industries and research institutes to analytical results of interaction soil-foundation related systems, reveals the importance of the dynamic impedance functions than ever before. The dynamic impedance function relations are presented for massless rigid foundations which is possible to obtain dynamic response of foundations for different frequencies and masses accordingly. In this study, the dynamic impedance functions were investigated using physical modeling tests on sandy soil with finite thickness soil stratum over bedrock. The tests were carried out inside a steel container of dimensions 1*1*0.8m in length, width and height respectively which was filled into...
Numerical Modelling of Buried Pipelines at Different Angles in Soil Slopes under Dynamic Loading Based on Physical Shaking Table Tests
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
The purpose of presented thesis, is modeling of the buried pipelines in soil slopes under dynamic loading using experiments on the physical model. Hence, numerical models based on five physical models, which are built and experimented on Sharif University of Technology’s shaking table device, have been analyzed using ABAQUS finite element software. In each model, several pipes are buried in slope, and the angle-wise placement of pipes differs with respect to slope slide. For the purposes of modeling, the experiment box has been modeled as rigid body. In order to model the soil behavior, Strain –dependent nonlinear elasticity, and mohr-coulomb criterion, has been employed. In addition,...
The Study of Soild Slope Seismic Response using the Physical Model Test on the Shaking Table
, M.Sc. Thesis Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Evaluation of seismic slope stability is very important because it has a decisive role in estimating the earthquake damages. According to the past studies medium to large earthquakes, usually cause thousands landslides and many casualties and financial damages. Since nearly half a century ago, several methods have been developed for predicting the occurrence of landslides and permanent movements, but due to the influence of many parameters on the seismic stability of the slopes further researches is needed.In present study, to investigate the dynamic behavior of the slopes, three physical models of slopes had been made on shaking table in Sharif University of technology. These slopes have...
Evaluation of the Effect of Anisotropy on Cyclic Behavior of Sands with Hollow Cylinder Apparatus
, Ph.D. Dissertation Sharif University of Technology ; Jafarzadeh, Fardin (Supervisor)
Abstract
Direction of loading and magnitude of the intermediate principal stress have significant effect on the soil responses. In many of in-situ loading the direction of major principal stress is not coincide to the deposition direction of the soil. Also, the magnitude of the intermediate principal stress should be exerted in the three dimensional loading condition. A reliable assessment of the soil behavior and a good estimation of the soil parameters need to do tests in similar condition with in-situ. So the testing apparatus should be able to control the loading direction in various stress paths. Typical equipments used in the geotechnical laboratory have not the ability to control the magnitude...