University of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Study of Flow Hydraulics in Expansive Gradual Transitions Open ChannelsStudy of Flow Hydraulics in Expansive Gradual Transitions Open Channels111929410.22034/ceej.2019.9294FAAdelAsnaashariFaculty of Mirdamad Institution, GorganAmir AhmadDehghaniDepartment of Water Engineering, Gorgan University of Agricultural Sciences and Natural ResourcesAli AkbarAkhtariCivil Engineering, Faculty of Engineering, Razi University , KermanshahJournal Article20190921 Channel expansions are common in both natural and artificial open channels. With increasing cross-sectional dimensions in an expansion, the flow decelerates. Under Subcritical flow and steady flow conditions, reducing the flow velocity due to increasing the water pressure and adverse pressure gradient. In this study, the flow hydraulic along the expansive transition of rectangular to trapezoidal under subcritical flow has been investigated experimentally. Also, a three- dimensional numerical simulation of the flow pattern was developed using the fluent software with RSM turbulent model. Water surface and flow velocity profiles at different sections of transition were compared with experimental results. The results showed a good agreement between numerical and experimental results. Then, the efficiency of the transition and coefficient of energy head loss were calculated. The results show that with increasing the upstream Froude number, the efficiency of the transition and coefficient of energy head loss are decreased and increased, respectively. After calibration, the effect of inflow Froude numbers on flow separation zones, secondary currents, and bed shear stress along the transition was investigated numerically. Channel expansions are common in both natural and artificial open channels. With increasing cross-sectional dimensions in an expansion, the flow decelerates. Under Subcritical flow and steady flow conditions, reducing the flow velocity due to increasing the water pressure and adverse pressure gradient. In this study, the flow hydraulic along the expansive transition of rectangular to trapezoidal under subcritical flow has been investigated experimentally. Also, a three- dimensional numerical simulation of the flow pattern was developed using the fluent software with RSM turbulent model. Water surface and flow velocity profiles at different sections of transition were compared with experimental results. The results showed a good agreement between numerical and experimental results. Then, the efficiency of the transition and coefficient of energy head loss were calculated. The results show that with increasing the upstream Froude number, the efficiency of the transition and coefficient of energy head loss are decreased and increased, respectively. After calibration, the effect of inflow Froude numbers on flow separation zones, secondary currents, and bed shear stress along the transition was investigated numerically.https://ceej.tabrizu.ac.ir/article_9294_b4e21937e04846e57a618411197be447.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Unsteady state modeling of BTEX dispersion from an Industrial Incinerator using splitting methodUnsteady state modeling of BTEX dispersion from an Industrial Incinerator using splitting method1321930410.22034/ceej.2019.9304FANesarakEslamiEnvironmental Engineering Research Center, Faculty of Chemical Engineering, Sahand University of Technology, TabrizEsmaeilFatehifarEnvironmental Engineering Research Center, Faculty of Chemical Engineering, Sahand University of Technology, TabrizMohammad AliKaynejadEnvironmental Engineering Research Center, Faculty of Civil Engineering, Sahand University of Technology, TabrizJournal Article20190921https://ceej.tabrizu.ac.ir/article_9304_05b38c4d18e26b6b04393a2073813322.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Evaluation of Lateral Loads Effect on Micropile GroupsEvaluation of Lateral Loads Effect on Micropile Groups2334929510.22034/ceej.2019.9295FAVahidAsghariDepartment of Civil Engineering, Tabriz Branch, Islamic Azad University, TabrizRasoulJaniDepartment of Civil Engineering, Tabriz Branch, Islamic Azad University, TabrizJournal Article20190921 Micropiles have been widely accepted by engineers in recent decades. Experimental observations show that the behavior of the micropiles against the earthquake forces is better because of their high ductility. In this research, was investigated the behavior of foundations based on micropiles under vertical loads and seismic loads. The present study focuses on finite element method of seismic behavior of micropiles. In this study, the vertical lateral boundaries of the soil were modeled to eliminate the reflection of the incoming waves inside the model. Parametric studies have been performed on independent variables such as frequency of inbound movement, soil properties, micropiles distance. Micropiles have been widely accepted by engineers in recent decades. Experimental observations show that the behavior of the micropiles against the earthquake forces is better because of their high ductility. In this research, was investigated the behavior of foundations based on micropiles under vertical loads and seismic loads. The present study focuses on finite element method of seismic behavior of micropiles. In this study, the vertical lateral boundaries of the soil were modeled to eliminate the reflection of the incoming waves inside the model. Parametric studies have been performed on independent variables such as frequency of inbound movement, soil properties, micropiles distance.https://ceej.tabrizu.ac.ir/article_9295_6ab3cbdad0a0db58f658df0a4d4d60c6.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Study of the Effect of Cross-sectional Geometry of Single and Twin Tunnels on the Ground Surface Settlement (Case study: Isfahan’s Metro Tunnel)Study of the Effect of Cross-sectional Geometry of Single and Twin Tunnels on the Ground Surface Settlement (Case study: Isfahan’s Metro Tunnel)3546929610.22034/ceej.2019.9296FAMohammadAmiriFaculty of Engineering, University of HormozganSaeedRajabiMaster Student, Islamic Azad University Isfahan (Khorasgan) University, Faculty of EngineeringMahdiehDarabiBu-Ali Sina University, Faculty of EngineeringJournal Article20190921Worldwide, rapid population growth in major cities has resulted in increased pressure on existing transportation systems. With underground transportation systems already in place, newly constructed tunnels might be needed to construct in close proximity to each other to make efficient use of the underground space (Baziar et al., 2016; Maleki, 2001). With population growth and urbanization, opening metro tunnels is an effective method for reducing traffic congestion in urban areas. Metro tunnels tend to be in the form of twin tunnels and close to each other or urban infrastructures. In these conditions, the interaction between tunnels and consequently their effects on subsurface movements, ground surface settlement, distribution of induced stresses and properties of tunnel lining are the most important factors that must be considered in tunnel design. Consequently, the above listed parameters have been studied by using a variety of approaches, including in situ observation, physical model testing and numerical modeling (Peck 1969; and Ranken, 1977; Karakus et al. 2007, Talebinejad et al. 2014; Yasitli, 2014).Worldwide, rapid population growth in major cities has resulted in increased pressure on existing transportation systems. With underground transportation systems already in place, newly constructed tunnels might be needed to construct in close proximity to each other to make efficient use of the underground space (Baziar et al., 2016; Maleki, 2001). With population growth and urbanization, opening metro tunnels is an effective method for reducing traffic congestion in urban areas. Metro tunnels tend to be in the form of twin tunnels and close to each other or urban infrastructures. In these conditions, the interaction between tunnels and consequently their effects on subsurface movements, ground surface settlement, distribution of induced stresses and properties of tunnel lining are the most important factors that must be considered in tunnel design. Consequently, the above listed parameters have been studied by using a variety of approaches, including in situ observation, physical model testing and numerical modeling (Peck 1969; and Ranken, 1977; Karakus et al. 2007, Talebinejad et al. 2014; Yasitli, 2014).https://ceej.tabrizu.ac.ir/article_9296_ad222ad982e43d40ba2921afc2551c17.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Extension of Algorithm for Support Non-Uniform Record Using Time Domain 3D Boundary Elements MethodExtension of Algorithm for Support Non-Uniform Record Using Time Domain 3D Boundary Elements Method4757929710.22034/ceej.2019.9297FAMohsenIsariFaculty of Civil Engineering, University of Tabriz, TabrizRezaTarinejadFaculty of Civil Engineering, University of Tabriz, TabrizAbdullahSohrabi-BidarSchool of Geology, University of TehranJournal Article20190921It is well established that the seismic ground response of surface topographies may differ from those of free field motion during earthquakes. Although the topography effect on ground response can be crucial when the wavelength is comparable to irregularity dimensions, only a few building codes have considered this issue. This is because of the complex nature of seismic wave scattering by topographical structures, which can only be solved accurately and economically using advanced numerical methods under realistic conditions. Among the numerical methods, the BEM is a very effective tool for dynamic analysis of linear elastic bounded and unbounded media. In this research, a three-dimensional model of the Pacoima dam site is prepared. Time domain 3D boundary element method is used to apply the non-uniform excitation at the dam supports. This model is subjected to the vertically propagating incident S waves. Time delay can be characterized by calculating the value of time delay for which the cross-correlation between two records is maximized. Finally, to obtain the time delay in topographic site, a function considering effective parameters such as the height from the canyon base, wave velocity and predominant frequency, is presented. Furthermore, a code was developed for generating the spatial variation of seismic ground motions.It is well established that the seismic ground response of surface topographies may differ from those of free field motion during earthquakes. Although the topography effect on ground response can be crucial when the wavelength is comparable to irregularity dimensions, only a few building codes have considered this issue. This is because of the complex nature of seismic wave scattering by topographical structures, which can only be solved accurately and economically using advanced numerical methods under realistic conditions. Among the numerical methods, the BEM is a very effective tool for dynamic analysis of linear elastic bounded and unbounded media. In this research, a three-dimensional model of the Pacoima dam site is prepared. Time domain 3D boundary element method is used to apply the non-uniform excitation at the dam supports. This model is subjected to the vertically propagating incident S waves. Time delay can be characterized by calculating the value of time delay for which the cross-correlation between two records is maximized. Finally, to obtain the time delay in topographic site, a function considering effective parameters such as the height from the canyon base, wave velocity and predominant frequency, is presented. Furthermore, a code was developed for generating the spatial variation of seismic ground motions.https://ceej.tabrizu.ac.ir/article_9297_78e30cbcc1cf9fa9248f33d44ec566a1.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Optimization of Pile Length in Earth Slope StabilizationOptimization of Pile Length in Earth Slope Stabilization5969929810.22034/ceej.2019.9298FAMohammadHajiaziziFaculty of Engineering, Razi University, KermanshahAlirezaMoradiFaculty of Engineering, Razi University, KermanshahMasoudNasiriFaculty of Engineering, Razi University, KermanshahAhmad RezaMazaheriFaculty of Engineering, Ayatollah Borujerdi University, BorujerdHasanSharafiFaculty of Engineering, Razi University, KermanshahJournal Article20190921The present paper, illustrated the results of numerical investigation and a series of experimental modeling on optimization of pile length in reinforcing earth slopes using piles. In this paper, the length of different piles with various diameters analyzed and the relationship for optimal length proposed. Stabilization of earth slopes and proposing different methods is one of the main issues in geotechnical engineering. Using numerical and analytical methods in stabilization of earth slopes reinforced by piles are common method, which, carried out by lots of researchers. Finding the optimal length of piles in reinforced slopes is an important matter that reduces the expenses and make the project economical. The present paper, illustrated the results of numerical investigation and a series of experimental modeling on optimization of pile length in reinforcing earth slopes using piles. In this paper, the length of different piles with various diameters analyzed and the relationship for optimal length proposed. Stabilization of earth slopes and proposing different methods is one of the main issues in geotechnical engineering. Using numerical and analytical methods in stabilization of earth slopes reinforced by piles are common method, which, carried out by lots of researchers. Finding the optimal length of piles in reinforced slopes is an important matter that reduces the expenses and make the project economical. https://ceej.tabrizu.ac.ir/article_9298_8a3055e34adb77ef3b4e093cbcd6937c.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Investigating the Effectiveness of Urmia Lake Different Restoration Scenarios Using a 2D Hydrodynamic ModelInvestigating the Effectiveness of Urmia Lake Different Restoration Scenarios Using a 2D Hydrodynamic Model7181929910.22034/ceej.2019.9299FAHassanHamidi RaziFaculty of Agriculture, University of Tarbiat Modares, TehranMehdiMazaheriFaculty of Agriculture, University of Tarbiat Modares, TehranJamalMohammadvali SamaniFaculty of Agriculture, University of Tarbiat Modares, TehranMarcosCarvajalino FernandezOceanography and climate research group, Institute of Marine Research, P.O. Box 1870 Nordnes, 5817 Bergen, NorwayJournal Article20190921Urmia lake is located in a closed basin between 37° 04’ N and 38° 17’ N latitude and 45° E and 46° E longitude in the northwest of Iran and the second extremely-largest saline lake in the world (Sima and Tajrishy, 2013). It has been recently much regarded due mainly to its dramatic area shrinkage and desiccation. The lake, because of its unique natural and ecological importance, has been considering as a National Park (Abbaspour and Nazaridoust, 2007), Ramsar Site (https://rsis.ramsar.org) and UNESCO Biosphere Reserve (http://www.unesco.org). Following the continuous drying process of Urmia Lake as well as considering its geographical and political location, livelihood, identity and historical dependency of the regional people to it, its restoration and prevention from drying up have become highlighted so far. According to several universal experiences connected with partial restoration approach and rehabilitation of the lakes coping with dryness (e.g. Micklin, 2007), Urmia Lake partial restoration is also discussed among Urmia Lake Restoration Program (http://ulrp.sharif.ir) experts. To this end, this study aims at investigating the partial restoration-related scenarios arisen through ULRP specialists using a 2D MOHID Water hydrodynamic system.Urmia lake is located in a closed basin between 37° 04’ N and 38° 17’ N latitude and 45° E and 46° E longitude in the northwest of Iran and the second extremely-largest saline lake in the world (Sima and Tajrishy, 2013). It has been recently much regarded due mainly to its dramatic area shrinkage and desiccation. The lake, because of its unique natural and ecological importance, has been considering as a National Park (Abbaspour and Nazaridoust, 2007), Ramsar Site (https://rsis.ramsar.org) and UNESCO Biosphere Reserve (http://www.unesco.org). Following the continuous drying process of Urmia Lake as well as considering its geographical and political location, livelihood, identity and historical dependency of the regional people to it, its restoration and prevention from drying up have become highlighted so far. According to several universal experiences connected with partial restoration approach and rehabilitation of the lakes coping with dryness (e.g. Micklin, 2007), Urmia Lake partial restoration is also discussed among Urmia Lake Restoration Program (http://ulrp.sharif.ir) experts. To this end, this study aims at investigating the partial restoration-related scenarios arisen through ULRP specialists using a 2D MOHID Water hydrodynamic system.https://ceej.tabrizu.ac.ir/article_9299_941a929a4b3258c30d96fb3211f269ce.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Rainfall Forecast by Integrated Model ARMA-ARCH for West of Urmia Lake Catchment basinRainfall Forecast by Integrated Model ARMA-ARCH for West of Urmia Lake Catchment basin8594930010.22034/ceej.2019.9300FAHoseinRezaieFaculty of Agriculture Engineering, University of UrmiaMahdiKhoshbakht TizkharabFaculty of Agriculture Engineering, University of Urmia (International Campus)Journal Article20190921Forecasting rainfall situation has paramount importance for water resources engineering. In this field, linear time series models are widely used in hydrology. Models of ARMA family have always had weaknesses which can be solved by integration of ARMA linear time series models with nonlinear time series models such as ARCH. In economy, the sequence of error variance in one model of errors’ size in previous time periods is the main assumption for Autoregressive conditional heteroscedastic models (Engle, 1982). At first, models of ARCH family for time series were used in financial and economic problems. In problems related to hydrology, ARCH models have been studied less.Forecasting rainfall situation has paramount importance for water resources engineering. In this field, linear time series models are widely used in hydrology. Models of ARMA family have always had weaknesses which can be solved by integration of ARMA linear time series models with nonlinear time series models such as ARCH. In economy, the sequence of error variance in one model of errors’ size in previous time periods is the main assumption for Autoregressive conditional heteroscedastic models (Engle, 1982). At first, models of ARCH family for time series were used in financial and economic problems. In problems related to hydrology, ARCH models have been studied less.https://ceej.tabrizu.ac.ir/article_9300_8382745c03ac6223944b6d08446435d5.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Uncertainty Analysis of Seepage Flow in Soil Foundation of Small Concrete DamUncertainty Analysis of Seepage Flow in Soil Foundation of Small Concrete Dam95105930110.22034/ceej.2019.9301FAAhmadSharafatiCivil Engineering Department, Science and Research Branch, Islamic Azad University, TehranSeyed BehnamMirfakhraeeCivil Group, Technical and Engineering Department, Shar-e-Qods Islamic Azad UniversityJournal Article20190921Hydraulic conductivity of soil has spatial variability due to complex configuration of soil. Therefore, regarding constant hydraulic conductivity in seepage analysis of soil foundation has high uncertainty.<br />In this study, seepage analysis of soil foundation in the small concrete dam was analyzed by considering uncertainty of hydraulic conductivity. In this respect, spatial variability of two-layer soil foundation was quantified using Monte Carlo simulation (Sharafati and Zahabiyoun 2014; Sharafati and Azamathulla 2018; Sharafati et al. 2018). Also, random variables were generated using Cholesky method and autocorrelated function of each layer.Hydraulic conductivity of soil has spatial variability due to complex configuration of soil. Therefore, regarding constant hydraulic conductivity in seepage analysis of soil foundation has high uncertainty.<br />In this study, seepage analysis of soil foundation in the small concrete dam was analyzed by considering uncertainty of hydraulic conductivity. In this respect, spatial variability of two-layer soil foundation was quantified using Monte Carlo simulation (Sharafati and Zahabiyoun 2014; Sharafati and Azamathulla 2018; Sharafati et al. 2018). Also, random variables were generated using Cholesky method and autocorrelated function of each layer.https://ceej.tabrizu.ac.ir/article_9301_18f59f1ba81e6746e8a27811f86679cf.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Seismic Performance of Low-Rise Slotted RC Shear WallsSeismic Performance of Low-Rise Slotted RC Shear Walls107116930210.22034/ceej.2019.9302FAMasoodFarzamFaculty of Civil Engineering, University of TabrizMohammadGhanizadehUniversity of Payame Noor, TabrizAbdolrezaSarvghad MogadamStructural Engineering Faculty, International Institute of EarthquakeJournal Article20190921https://ceej.tabrizu.ac.ir/article_9302_e0910c4b3befaf34206aedeb25dd6a62.pdfUniversity of TabrizJournal of Civil and Environmental Engineering2008-7918499520190823Numerical Examination of Stone Column for Liquefaction Diminution PotentialNumerical Examination of Stone Column for Liquefaction Diminution Potential119129930310.22034/ceej.2019.9303FAHalehMeshginghalamFaculty of Civil Engineering University of TabrizMasoudHajialilue BonabFaculty of Civil Engineering University of TabrizSeyyed KazemRazaviFaculty of Civil Engineering University of TabrizJournal Article20190921Stone columns are one of effective methods of confronting liquefaction in saturated sands. The main objectives of this method is to increase soil strength and pore water drainage rate in surrounding soils, considering higher permeability of stone column materials. Different researchers have studied the effects of using stone columns on reducing liquefaction potential. Generally, these studies can be classified as numerical and experimental studies. Considering the fact that interactions between stone column and soil are tridimensional, the aim of present study is numerical investigation of application of current method in decreasing liquefaction potential.Stone columns are one of effective methods of confronting liquefaction in saturated sands. The main objectives of this method is to increase soil strength and pore water drainage rate in surrounding soils, considering higher permeability of stone column materials. Different researchers have studied the effects of using stone columns on reducing liquefaction potential. Generally, these studies can be classified as numerical and experimental studies. Considering the fact that interactions between stone column and soil are tridimensional, the aim of present study is numerical investigation of application of current method in decreasing liquefaction potential.https://ceej.tabrizu.ac.ir/article_9303_aa8a187f169e1e31768d9ee591be6234.pdf