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  1. admin
    Phosphorus Removal from Aqueous Solutions by Bentonite: Effect of Al2O3 Addition Original Article, C47 Panahi Osalo T, MerufiniaE, Esmat Saatlo M. Journal. Civil Eng. Urban. 3(5):317-322. 2013 ABSTRACT:Phosphorus is the main nutrient responsible for eutrophication of aquatic ecosystems; therefore, it is important to develop new processes to remove phosphorus from aqueous solutions. In this research, performance, kinetics, and adsorbing isotherms of Bentonite and Bentonite- Alumina compound (10% Alumina (Al2O3), 90% Bentonite) were investigated. According to the results of this study, the Langmuir adsorption model was best to describe adsorption equilibrium data for Bentonite-Alumina mixture and Bentonite (r2=0.999 for Bentonite-Alumina mixture and r2=0.996 for Bentonite). The Langmuir Isotherm parameters for Bentonite and Bentonite-Alumina were Qm=15.2, 18.1 mg/g and K=4.3, 5.5 L/mg, respectively. Moreover, the Freundlich Isotherm parameters were K=6.6, 9.12 and n=3.05, 3.7, respectively. Bentonite-Alumina mixture was found to more effective for the removal of phosphorus than Bentonite (97% in 140 min in comparison to 90% in 140 min). Keywords:Phosphorous Removal, Absorbents, Bentonite, Alumina, Algae, Eutrophication منبع: [Hidden Content] دانلود: [Hidden Content].,47-317-322.pdf J. Civil Eng. Urban.,47-317-322.pdf
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    The Effect of Post-Yield Stiffness Ratio on Strength Reduction Factors Due to Ductility with an Emphasis on Iran's Strong Ground Motions Original Article, C46 Akbarian B, Barghian M Journal. Civil Eng. Urban. 3(5):310-316. 2013 ABSTRACT:Inelastic strength demands can be calculated from elastic strength demands by strength reduction factors. These factors are also called response modification factors which depend on some parameters such as ductility, over-strength, redundancy and damping. The main objective of this study is to determine the strength reduction factor due to ductility for non-deteriorating bilinear single degree of freedom systems which have positive post-yield stiffness or strain hardening for some Iran’s major earthquake records. Compact structural steel sections and some seismic base isolation systems are some examples of mechanical systems with bilinear hysteresis behaviour. In this research, The effect of positive post-yield stiffness ratio is studied for both constant-ductility response spectra or inelastic strength demand spectra and strength reduction factors due to ductility. The evaluation of ductility factor requires large computational efforts. To overcome this problem, the PRISM software was used. A functional form was proposed and parameters were evaluated by the least square error method. This functional form is assumed to be a function of post-yield stiffness ratio, target ductility factor and structural period. For this purpose, the El-Centro, Tabas, Naghan and Abbar ground motions were used. Keywords:Inelastic Strength Demand, Strength Reduction Factor, Target Ductility Factor, Bilinear Hysteresis Model منبع: [Hidden Content] دانلود: [Hidden Content].,46-310-316.pdf J. Civil Eng. Urban.,46-310-316.pdf
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    یکی از ویژگی های فروم اینست که در آن افراد مختلف با نظرات مختلف فعالیت میکنند که ممکن است در یک موضوع تخصصی نظرات متفاوت یا حتی متضادی داشته باشند. در برخی از تاپیکها ممکن است به یک سوال واحد دو یا چند کاربر چند جواب متفاوت بدهند که این مساله برای کاربران دیگری که بعداً از آن تاپیک بازدید میکنند ممکن است باعث سردرگمی شود. یکی از راهکارهایی که در انجمن سایت برای این موضوع پیش بینی شده است اینست که کاربر شروع کننده تاپیک بعد از اینکه تشخیص داد که کدام پاسخ صحیحتر یا به بیان دیگر بهترین پاسخ است آن را به عنوان بهترین پاسخ انتخاب کند و از آن پس آن پاسخ در ابتدای تاپیک به دیگران نمایش داده میشود. برای این موضوع کافیست که در پست مورد نظر در آن تاپیک توسط شروع کننده تاپیک یا یکی از مدیران انجمن گزینه «علامت زدن به عنوان حل شده» کلیک شود.
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    Spatial Analysis of Urban Inequality in Qazvin Province Original Article, C45 Salehi M, Budaqov B. Journal. Civil Eng. Urban. 3(5):300-309. 2013 ABSTRACT:As a descriptive-analytical study, this paper aims to investigate and analyze spatial inequalities among different cities of Qazvin province during 1976-2006, using statistical models and software. Regarding population, social, economic, health, cultural, infrastructural, transportation and communicational indicators in 25 cities of Qazvin province, Qazvin, Abgarm, Narje are most developed, and KhakAli, Sagez Abad, Aavaj, Abgarm, Zia Abad, and Sirdan, are deprived cities, respectively. Coefficient of variance model indicates the most inequality belongs to cultural indicator and the least belong to social indicators. Based on the results of the study, economical factor is more effective on spatial structure of all cities in Qazvin. Moreover, infrastructural and cultural factors are influential in cities of the province. Keywords:Spatial Analysis, Statistical Analysis, Urban Inequality, Qazvin Province منبع: [Hidden Content] دانلود: [Hidden Content].,45-300-309.pdf J. Civil Eng. Urban.,45-300-309.pdf
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    Estimation of Suspended Sediment Load Using Genetic Expression Programming Original Article, C44 Sheikhalipour Z, Hassanpour F. Journal. Civil Eng. Urban. 3(5):292-299. 2013 ABSTRACT:Accurate estimation of suspended sediment load carried by a natural river is important for river engineering and water resources projects. In recent years, using ­ smart systems to increase accuracy of estimating of river sediments are common. In this study were used the­ Genetic Expression Programming (GEP) in order to estimate suspended sediment load in Sistan River. Root mean square error (RMSE), mean bias error (MBE) and determination coefficient (R2) statistics are used for evaluating the accuracy of the models. GEP is found that scenario 3 with four function and RMSE=0, MBE=2.69×10-4, R2=1 in train period and RMSE=0, MBE=2.4×10-4 and R2=1 in test period are superior in estimating suspended sediment load as the best accurate model. The modeling approach presented in this paper can be potentially used to reduce the frequency of costly operations for sediment measurement where hydrological data is readily available.Also ­estimation of suspended sediment load using other AI methods such as Particle Swarm Optimization, Tabu Search in Sistan River are suggested. Keywords: Genetic Expression Programming (GEP), Artificial Intelligence (AI), Statistic Indicators, Suspended Sediment Load. منبع: [Hidden Content] دانلود: [Hidden Content].,44-292-299.pdf J. Civil Eng. Urban.,44-292-299.pdf
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    An Independent Robust Modal PID Control Approach for Seismic Control of Buildings Original Article, C43 Etedali S, Sohrabi M.R, Tavakoli S. Journal. Civil Eng. Urban. 3(5):279-291. 2013 ABSTRACT:In this paper, an independent robust modal PID control approach for seismic control of structures is proposed. First, state space equations of the structure are transformed into modal coordinates. Second, the parameters of the modal PID control are separately designed in a reduced modal space. To create a good trade-off between the performance and robustness of the modal controller, the modal feedback gain is determined using genetic algorithms. Then, the feedback gain matrix of the controller is obtained based on the contribution of modal responses to the structural response. Considering four earthquakes and twelve performance indices, the performance of the controller is investigated for an 11-story realistic building equipped with ATMD. Simulation results show that the proposed controller significantly performs better than the LQR in reduction of structural responses. Unlike the LQR, the proposed controller is able to significantly reduce structural responses in strong earthquakes at the cost of demanding a higher control force and external power. Furthermore, it maintains appropriate performance in dealing with model uncertainties. In addition, the proposed controller has several advantages over conventional modern controllers in terms of simplicity and reduction of required sensors to the number of controlled stories. Keywords:Seismic Control, Active Tuned Mass Damper, Modelling Error, Robust Control, PID Controller منبع: [Hidden Content] دانلود: [Hidden Content].,43-279-291.pdf J. Civil Eng. Urban.,43-279-291.pdf
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    Errors Estimation of Different Numerical Integration Techniques on Stiffness Matrix and Stress Intensity Factor in XFEM Original Article, C42 Ghohani Arab H, Ghasemi M.R. Journal. Civil Eng. Urban. 3(5):265-278. 2013 ABSTRACT:One of the new methods in the analysis of cracked structures is extended Finite Element Method (XFEM). In this method, unlike the conventional finite element method to calculate the integral of stiffness matrix using Gauss quadrature rule, accuracy of stiffness matrix of cracked elements is reduced. This article builds on the relationship between errors in the calculations if one uses different methods to calculate the stiffness matrix integral. The three methods of integration used and presented here are trapezoidal rule integration, Gauss quadrature integration and sub element rule integration. The average stiffness matrix error and maximum stiffness matrix errors were considered as the assessing criteria. L2-norm and energy norm criteria were also used. Finally accuracy of stress intensity factor (SIF) determined by XFEM were compared with different integration rules conventionally used in the literature. Keywords:Gauss Quadrature Integration, SIF ,Stiffness Matrix, Sub Element Rule Integration, Trapezoidal Rule Integration, XFEM منبع: [Hidden Content] دانلود: [Hidden Content].,42-265-278.pdf J. Civil Eng. Urban.,42-265-278.pdf
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    Equivalent Static Analysis of the Kabud Tower of Maragheh Original Article, C41 Khodayari R, Karimi Moridani K, Yadegari A. Journal. Civil Eng. Urban. 3(5): 260-264. 2013 ABSTRACT:This paper investigates the behavior of masonry materials under lateral loads. The specific structure investigated in this paper is The Kabud Tower which is attributed to Hulagu khan’s mother and is related to Seljuk era in1197 BC (539 Hegira). Since this structure is made of two distinct parts, stone and brick with mortar, modeling of the elements is limited to distinct ways with contact bond in ANSYS. Because the first step for strengthening is detecting of the weak points, the structure was analyses against lateral loads. Concerning the existence of crack on the structure, this structure was modeled on cracked and non –cracked models and then effect of present crack on the behavior of the structure was investigated. Keywords: Masonry structure, kabud tower, equivalent static analysis, modal analysis منبع: [Hidden Content] دانلود: [Hidden Content].,41-260-264.pdf J. Civil Eng. Urban.,41-260-264.pdf
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    An Investigation of Efficiency and Accuracy of Energy-Based Capacity Spectrum in Estimating the Seismic Demands of Buildings Original Article, C40 Vakili H, Shakeri K, Seyyedi Viand S.M, Azadi Hir M. Journal. Civil Eng. Urban. 3(5):251-259. 2013 ABSTRACT:In the conventional methods of pushover analysis, the capacity spectrum is obtained with linking roof displacement to base shear, while this relationship only is meaningful in pushover analysis with load pattern that is proportional to the first mode. In the higher modes, changes of the roof displacement is not proportional to the changes of other stories displacement, and even in some cases roof displacement is decreased with increasing base shear and reverses. Therefore, using the roof displacement for establishing the capacity spectrum in the higher modes is faced with ambiguities. Using the energy method for establishing the capacity spectrum of structure is one of the proposed methods to eliminate these ambiguities. In this method, not only the amount of the roof displacement, but also the amount and the sign of other stories displacements participate in the establishment of capacity spectrum of structure. In this research, the accuracy and efficiency of energy-based capacity spectrum has been studied on two steel moment-frame buildings under different earthquakes for using in different pushover analysis with various load patterns. The results show that using the energy method for establishing the capacity spectrum not only eliminate the existent ambiguities and problems in establishment of capacity spectrum, but also the responses of the different nonlinear static analysis by using the energy-based capacity spectrum instead of the conventional capacity spectrum (based on roof displacement) have better accuracy and efficiency. Keywords: Seismic Demands, Modal Pushover Analysis, Higher Modes, Capacity Spectrum, Energy Method منبع: [Hidden Content] دانلود: [Hidden Content].,40-251-259.pdf J. Civil Eng. Urban.,40-251-259.pdf
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    Neighbourhood Classification and Organization of Informal Settlements Using Development Method of Morris (Case Study: Bonab City) Original Article, C39 Rashidi Ebrahim Hesari A, Chekaniazar M. Journal. Civil Eng. Urban. 3(5):240-250. 2013 ABSTRACT:Informal settlement is influenced by unequal global political-economic relationship, weakness of national programs in middle level and urban planning in micro level. Ever increasing expansion of the phenomena lead to the emergence, development and expansion of conflict in the urban soul and body, and creates abnormal biological conditions with dissimilar development indicators that not only questions equitable allocation of resources and services in line with social justice, but challenges sustainable development of urban life. However, any urban planning and designing considers comprehensive content - physical, scientific - practical understanding of urban systems, subsystems and outreach systems in relativist position of space and time; therefore, it is necessary to understand neighborhood and informal settlements based on different physical, business, economic, social, cultural, and infrastructure indicators. In this regard, development method of Morris is used. To investigate neighborhood development, physical, economic, social and infrastructural characteristics of all neighborhoods in Bonab city are studied. Results of the study show there is obvious difference between physical, economic, social and developmental indicators of neighborhoods in Bonab city that lead to inequitable distribution of services and resources. Finally, based on results of Morris development model and neighborhood classification, suggestions and priorities of neighborhood-oriented urban planning and informal settlement organizing are presented. Keywords:Informal Settlement, Quantitative Techniques, Urban Systems, Relativism, Organizing, Morris Development Model, Bonab City منبع: [Hidden Content] دانلود: [Hidden Content].,39-240-250.pdf J. Civil Eng. Urban.,39-240-250.pdf
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    An Energy Approach to Static Analysis of a Centrally Loaded Simply Supported Thin Rectangular Isotropic Plate Original Article, C38 Emma J.B, Sule S. Journal. Civil Eng. Urban. 3(5):236-239. 2013 ABSTRACT:In this paper, the numerical factors for deflection of a centrally loaded all round simply supported thin rectangular isotropic plate are determined using energy approach. The results obtained using energy approaches are compared with those obtained from literature. It is shown that results obtained using energy method are agreed favorably with those of other author serving as the exact solution showing the efficacy of the energy method in the determination of numerical factors for deflection of a centrally loaded simply supported thin rectangular isotropic plate. It is also found that the value of the numerical factors for deflection of all round simply supported thin rectangular isotropic plate is a function of the assumed polynomial function. Keywords:Numerical Factors, Rectangular Isotropic Plate, Exact Solution, Energy Approach, Polynomial Function منبع: [Hidden Content] دانلود: [Hidden Content].,38-236-239.pdf J. Civil Eng. Urban.,38-236-239.pdf
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    Dynamic characteristics of monthly rainfall in Tabriz under climate change Original Article, C37 Jani R, Ghorbani M.A, Saghafian B, Shamsaei A, zahabion B. Journal. Civil Eng. Urban. 3(4):225-235. 2013 ABSTRACT:Among the factors creating the changes in climate include ever-increasing population, changes in land usage and the development of industrial activities. Thus, studying the effect of this phenomenon on hydrological processes, in particular rainfall is considered as one of the most important issues concerning water engineering. Chaos theory is a tool that can be implemented besides other methods in modeling nonlinear, complicated hydrological phenomena like rainfall, due to its wonderful capabilities. In this study, monthly rainfall in Tabriz has been studied through this theory under historical and climate change conditions. In so doing, the statistical period of 1971 to the year 2000 was considered as the historical period, and the results obtained from the model LARS-WG were also considered under two scenarios in three future periods. The results indicated that historical period data having the fractal dimension of (5.96) has good chaotic nature. In the case of scenario A2, the data of all three series had good chaotic nature as well. In scenario B1, random investigation in all three periods will be appropriate. Keywords: Climate Change, Rainfall, Chaotic Theory, Tabriz, Lars-WG Model. منبع: [Hidden Content] دانلود: [Hidden Content].,37-225-233.pdf J. Civil Eng. Urban.,37-225-233.pdf
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    Increasing Development of the Cities and its Impact on the Environment Original Article, C36 Hasanov T.G, Sangi A, Abafat S. Journal. Civil Eng. Urban. 3(4):221-224. 2013 ABSTRACT:Cities are physical structures that have been built in the heart of nature by human beings. The growth rate of urbanization has been increased after the industrial revolution and urban sprawls are considered some kind of invasion of natural spaces around the city. Currently converting natural areas to urban residential spaces and urban application, conversion of natural forests to agricultural land and villa construction and road building, uncontrolled growth of consumer industries, pollution of water sources, increased artificial uses of the Earth and environmental pollution, have caused a lot of damages to normal appearance of the Earth and continuation of this trend can cause the interaction of nature and consequently make life of current and future generation face to face with danger. Environment as a development platform has an important role in the development of the cities and healthy environment and sustainable ecosystems not only provide necessary platform in development process but also, the appropriate environment for human being to live in and his appropriate participation in the process of human development. Therefore any operation of the nature to construct and develop the cities should take place after evaluation of the resources and regarding the capacities of the natural environment. No city enjoys being completely prepared to guarantee its future sustainability and environmental requirements, force urban planners to observe the requirements of sustainable development. Accordingly, they should organize urban system and modes of production and methods of urban life such that urban development moves towards environmental sustainability. In sustainable urban development the subject of conservation of the natural resources for the present and future through optimal use of the land and causing the least damages to its resources are considered. Keywords: Urban development, Environment, Sustainable Development منبع: [Hidden Content] دانلود: [Hidden Content].,36-221-224.pdf J. Civil Eng. Urban.,36-221-224.pdf
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    An Assessment of a Modal Pushover Method Based On 2DOF Modal System for Tall Asymmetric-Plan Buildings Original Article, C35 Seyyedi Viand S.M, Shakeri K, Vakili H, Azadi Hir M. Journal. Civil Eng. Urban. 3(4):216-220. 2013 ABSTRACT:Recently, a novel two-degrees-of-freedom (2DOF) modal system has been proposed by Lin and Tsai which considers bifurcating and interaction between modal translation and modal rotation. Also, they claim that the proposed system is accurate than the conventional single-degree-of-freedom (SDOF) modal system in estimating the seismic demands of asymmetric-plan buildings. In this paper, the efficiency of application of the proposed system for tall buildings is evaluated. Hence, a modal pushover analysis is performed for a sample tall asymmetric-plan building based on SDOF and 2DOF modal systems. Then, the seismic responses of building are estimated by utilizing nonlinear time history analysis (NTHA). Finally, the analytical results are compared. Results show that the efficiency of 2DOF modal system becomes considerable at high levels of building, in particular for rotational responses. Consequently, the new system may be an alternative to the SDOF modal system in estimating the seismic responses of asymmetric-plan buildings. Keywords: Asymmetric-Plan Buildings, Two-Degrees-Of-Freedom Modal Systems, Modal Pushover Analysis منبع: [Hidden Content] دانلود: [Hidden Content].,35-216-220.pdf J. Civil Eng. Urban.,35-216-220.pdf
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    Estimation of Channels Seepage using Seep/w and Evolutionary Polynomial Regression (EPR) modeling (Case Study: Qazvin and Isfahan Channels) Original Article, C34 Aghvami E, Abbaspour A, Ghorbani M.A, Salmasi F. Journal. Civil Eng. Urban. 3(4):211-215. 2013 ABSTRACT:Research and studies on the seepage of channels so far as man power and time and expense required for the experimental measurement of seepage canals or studies that require complex mathematical equations to solve difficult linear integral, need for a new and accurate way to predict the amount of seepage in canals before creation of it. Developing computer-based tools during the last two decades facilitates and develops of computational intelligence techniques. Seep/w and EPR are the new technique developed in recent years and at first it has been used for modeling environmental phenomena by providers. The use of these methods in water engineering has recently started and it is growing. However, in order to relative extent of these methods, collection efficiency in many ways remains a mystery. The results of modeling performed in seep/w for different initial conditions in canals including canal width, canal slope, water depth, the lining thickness, and depth to groundwater and accuracy of results on Qazvin and Isfahan canal were investigated. Keywords: EPR, Canals, Seepage, Seep/W منبع: [Hidden Content] دانلود: [Hidden Content].,34-211-215.pdf J. Civil Eng. Urban.,34-211-215.pdf
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    Benchmarking of the Design Principles of Traditional Architecture Original Article, C33 Honarjo M, Pashaei kamali F. Journal. Civil Eng. Urban. 3(4):207-210. 2013 ABSTRACT:Even though sustainable designing is the main discussion of nowadays architecture, all principles are practically concerned by our predecessors in ecological architecture. Traditional architecture of Iran considers tranquillity of interior space without utilizing energy consuming and pollutant devices and this architecture is very much capable of offering methods to use these kinds of energies and can be used for designing new monuments. Advancement in technology and improper use of this advancement has caused these techniques to be ignored and the non-recyclable fossil fuels to be used excessively. To replace clean energies with fossil fuels, regarding their high expenses and the risk to humans’ life, and to achieve sustainable architecture, old architecture of Iran shall be studied and their methods be used regarding the needs of present society. Keywords: Ecological, Traditional, Clean Energy منبع: [Hidden Content] دانلود: [Hidden Content].,33-207-210.pdf J. Civil Eng. Urban.,33-207-210.pdf
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    Investigation of Dam Construction Effects without Environmental Assessment (Case Study: Urmia Lake) Original Article, C32 Majediasl M, Sangi A. Journal. Civil Eng. Urban. 3(4):201-206. 2013 ABSTRACT:Feedbacks on numerous harmful problems in the environment have caused appearance of some human society’s sensitivity about the range of human’s non-limited activities in the environment which are done without considering environmental limitations during the economic development process in the recent decades. If environmental problems, along with technical and economic justifications are not considered, activities related to the water resources development program will result in irreparable and undesirable consequences. Drying up of the lake due to irregular exploitation of catchment basin water resources and construction of several dams on the branches of its rivers without environmental assessments have led to increase in the region’s temperature, appearance of sand and salt storms, destruction of potential agricultural land, flooding, change in cultivation pattern, hence jeopardizing the life of region’s people. Because of these, Natural ecosystems existing around the lake have been changed remarkably, and animates’ habitat in the lake is going to be destroyed. So, it is necessary to carry out an accurate evaluation before implementing water resources projects during the investigation of economic and technical justifications, so that any exploitation of nature can be done in the framework of the capabilities and potentials of natural environment. In this paper, we present some approaches to fight against undesirable consequences of dam construction, investigating environmental changes in Urmi a Lake. Keywords: Water Resources Development, Dam, Environment, Urmia Lake منبع: [Hidden Content] دانلود: [Hidden Content].,32-201-206.pdf J. Civil Eng. Urban.,32-201-206.pdf
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    Forecasting Daily Stream Flows of Vaniar River Using Genetic Programming and Neural Networks Approaches Original Article, C31 Roushangar K, Vojoudi Mehrabani F, Alami M.T Journal. Civil Eng. Urban. 3(4):197-200. 2013 ABSTRACT:This study compares three different artificial intelligence approaches, namely, gene expression programming (GEP), and artificial neural networks (ANN), in daily as well as monthly streamflow forecasting. Daily streamflow data from Vaniar River in the Northwestern Iran were used. Coefficient of determination, root mean square error and scatter index were used to compare simulation results. The study demonstrates that the optimal results were obtained from the triple-input models including streamflows of current and two previous days and that the GEP model performed better than the ANN model in daily streamflow forecasting. Keywords: Gene Expression Programming, Neural Networks, Forecasting منبع: [Hidden Content] دانلود: [Hidden Content].,31-197-200.pdf J. Civil Eng. Urban.,31-197-200.pdf
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    The Importance of Determining Damage Levels of the Bridges in Non-Linear Dynamic Analysis Original Article, C30 Karimi Moridani K, Khodayari R, Asadpour M. Journal. Civil Eng. Urban. 3(4):191-196. 2013 ABSTRACT:During past earthquakes, different modes of damage were observed in bridges; consequently in seismic evaluation of these structures, various Indexes were used to determine vulnerability of the structures against earthquake vibrations. In this paper, damage indexes of structural elements of bridge are introduced and suggested definitions for structure damage state are stated. Then, a three span bridge is analyzed using OpenSees non-linear analysis software, considering three-dimensional model under earthquake load and non-linear behavior. After calculating necessary outcomes of the elements and nodes, damage indexes of damage at the foundations and columns level were measured. The model is able to calculate responses and damage indexes of supports and joints. Using this model, damage level of bridge structure is determined based on tables, which determine necessity of retrofitting. Based on the result, decisions made based on each criterion are compared. The results show that exact specification of damage indexes for the estimation of the vulnerability of structures (bridges here) is very important. Keywords: OpenSees Model, Bridge, Damage levels, Reinforcement, Stiffness منبع: [Hidden Content] دانلود: [Hidden Content].,30-191-196.pdf J. Civil Eng. Urban.,30-191-196.pdf
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    Investigation and Evaluation of Artificial Neural Networks in Babolroud River Suspended Load Estimation Original Article, C29 Kia E, Emadi A.R, Fazlola R. Journal. Civil Eng. Urban. 3(4):183-190. 2013 ABSTRACT:Estimation of sediment load is a priority of the river management, dam's reservoirs and generally water projects. Because of nonlinear structure of sediment phenomena, the classical and common methods like sediment rating curve is not able to estimate sediment rate correctly. In recent years, artificial intelligence methods such as ANNs are recommended for solving the nonlinear problems and to achieve closer result to the actual data. In the present study, various combinations of flow discharge and sediment rate in present and past days were used as input parameters, while the suspended sediment load was used as output of the model. Then, by use of MATLAB software and different Neural Network such as MLP, RBF and GRNN, optimum architecture of networks is obtained based on four statistical indices viz. mean square error, mean bias error, modeling efficiency and determination coefficient for Ghoran Talar station in Babolroud River to compare with sediment rating curve. The results showed that MLP with combination of current discharge for estimate of current sediment has a better precision than other two neural networks. Also, the use of artificial neural network has a better performance than sediment rating curve method and recommended for river suspended load estimation. Keywords: Suspended Load, Perceptron, Neural Network, Rating Curve منبع: [Hidden Content] دانلود: [Hidden Content].,29-183-190.pdf J. Civil Eng. Urban.,29-183-190.pdf
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    Experimental Study on the Flexural Behavior of Reinforced Concrete Beams as Replacement of Copper Slag as Fine Aggregate Original Article, C28 Arivalagan.S Journal. Civil Eng. Urban. 3(4):176-182. 2013 ABSTRACT:Researchers studied and developed waste management strategies to apply for advantages for specific needs. Owing to the scarcity of fine aggregate for the preparation of mortar and concrete, partial replacement of Copper Slag with sand have been attempted. The effects of replacing fine aggregates by copper slag on the compressive strength of cubes, split tensile strength of cylinders and flexural strength of beams are evaluated in this study. Copper slag is obtained as waste product from the sterlite industries. Investigations were carried out to explore the possibility of using copper slag as a replacement of sand in concrete mixtures. The test results of concrete were obtained by adding copper slag to sand in various percentages ranging from 0%, 20%. 40% 60%, 80% and 100%. All specimens were cured for 28 days before compression strength test ,splitting tensile test and flexural strength. The highest compressive strength obtained was 35.11MPa (for 40% replacement) and the corresponding strength for control mix was 30MPa. This results of the research paper showed that the possibility of using copper slag as fine aggregate in concrete. The results showed the effect of copper slag on RCC concrete elements has a considerable amount of increase in the compressive, split tensile, flexural strength characteristics and energy absorption characteristics. Keywords: Copper Slag Concrete, Compressive Strength, Split Tensile Strength, Flexural Strength, Energy Absorption Capacity منبع: [Hidden Content] دانلود: [Hidden Content].,28-176-182.pdf J. Civil Eng. Urban.,28-176-182.pdf
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    The Study of Effect of Dredging and Dike Construction on the Flow Hydraulic and Reduction of Flood in Downstream of the River (Case Study: Karun River Downstream Between Ahvaz and Farsyat) Original Article, C27 Monjezi R, Heidarnejad M, Asadi Lor M, Hoseini E. Journal. Civil Eng. Urban. 3(4):170-175. 2013 ABSTRACT:The aim of this study is to simulate a numerical model for flood spreading and to control it in Karoun River in the downstream of Ahvaz to Farsyat which is affected by dredging and the construction of dike. Using the HEC-RAS 4.1 software, one-dimensional flow model in this field was simulated. After entering the data to the model and calibration, the model was run based on selected design flow rates, and water levels were calculated and areas of flood spreading were defined. Then, the mathematical model was run based on the dredging and dike construction. Due to lack of efficiency of dredging operations for flood control and the lack of a suitable location for deflecting flow, the only practical and cost-effective method for controlling the flood of the Karoun River in the studied interval is to construct a dike with designed height. Keywords: Karoun River, Flood, HEC-RAS Model, Dike, Dredging منبع: [Hidden Content] دانلود: [Hidden Content].,27-170-175.pdf J. Civil Eng. Urban.,27-170-175.pdf
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    Optimal Cost Design of the Water Distribution Network Using the Meta-Heuristic Methods Original Article, C26 Daneshfaraz R. Journal. Civil Eng. Urban. 3(4):164-169. 2013 ABSTRACT:Today, optimal cost design of water distribution networks is one of the fundamental issues in water management plans. In recent years, high accuracy of meta-heuristic methods has gained attention of researchers. In this research, genetic algorithm and harmony search methods were used for optimal cost design of water distribution network in Kourtay village, Khoy. The results showed the significant ability of the methods, since the design costs were decreased by 8% and 10% using the genetic algorithm and harmony search algorithm, respectively. Furthermore, the Harmony search method was found more optimal and faster than the genetic algorithm. Keywords: Economic Optimization, Genetic Algorithm, Harmony Search Algorithm, Water Distribution Network منبع: [Hidden Content] دانلود: [Hidden Content].,26-164-169.pdf J. Civil Eng. Urban.,26-164-169.pdf
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    The Effect of Geometric Parameters and Foundation Depth on Scour Pattern around Bridge Pier Original Article, C25 Eghbali P, Dehghani A.A, Arvanaghi H, Menazadeh M. Journal. Civil Eng. Urban. 3(4):156-163. 2013 ABSTRACT:Scour around bridge foundations is one of the major causes of serious damage to the bridge. In this study, the effect of shape, level and position angle of foundation on scour pattern was investigated experimentally. The experiments were conducted for 4 foundation shapes including; square, cylinder, aerodynamic along and across the channel, 5 foundation depths and 7 foundation alignments. The results show that the scour depth depends on the foundation depth, shape and foundation alignment to the approach flow. The best foundation shape which leads to minimum scour, was aerodynamic shape along the channel, square, aerodynamic across the channel and cylindrical shape, respectively. The results also show that positioning of foundation below the initial channel bed, leads to less values of scour depth around bridge pier. Also the best angle for positioning of foundation is zero, i.e. parallel to flow direction. Analyses of results also show that the appropriate level for positioning the foundation is 25 to 50 % pier diameter below the channel bed. Keywords:Local Scour, Non-Uniform Bridge Pier, Foundation Shape, Foundation Depth, Position Angle of Foundation منبع: [Hidden Content] دانلود: [Hidden Content].,25-156-163.pdf J. Civil Eng. Urban.,25-156-163.pdf
  25. admin
    Determination of Energy Dissipation in Stepped Spillways Using Finite Element and Finite Volume Methods Original Article, C24 Shoja F, Nikpour M.R, Sadeghi H. Journal. Civil Eng. Urban. 3(4):150-155. 2013 ABSTRACT:Accurate and suitable design of Spillways as major parts of dams is very important in the stability and safety of dams. In this study, flow over stepped spillway was simulated in 2D by solving poisson functions of stream and pressure in Finite Element method and with analyzing k-ε turbulence and volume of fluid models in Finite Volume technique. Also a comparison was done between the results of numerical models and measured values in order to investigate the accuracy of the models in calculation of energy dissipation. The relative error percent average of energy dissipation calculation using Finite Element and Finite Volume approaches was achieved 2.85% and 1.26%, respectively. Results showed Finite Volume approach could be employed slightly better than Finite Element method in modelling flow hydraulic over stepped spillway. Keywords: Finite Element, Finite Volume, Stepped Spillway, Turbulence Model, Volume of Fluid Model منبع: [Hidden Content] دانلود: [Hidden Content].,24-150-155.pdf J. Civil Eng. Urban.,24-150-155.pdf

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