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  1. admin
    معماری از منظر زیبایی شهری، مصاحبه با جناب دکتر حافظی (معمار برج میلاد) منبع: [Hidden Content] آشنایی با رزومه میهمان این شماره از رادیو 808: دکتر محمدرضا حافظی ، دبیرکارگروه معماری و شهرسازی سوابق تحصیلی فوق لیسانس معماری از دانشگاه شهید بهشتی دکترای معماری از دانشکده مهندسی عمران لیدز - انگلستان سوابق اجرایی عضو مرکز تحقیقات وزارت مسکن و شهرسازی مرکز تحقیقات ساختمان و مسکن (تاکنون) عضو کمیته مقررات ملی ساختمان مبحث وزارت مسکن و شهرسازی مرکز تحقیقات ساختمان و مسکن (تاکنون) سوابق آموزشی و پژوهشی عضو هیئت علمی دانشگاه شهید بهشتی (تاکنون) عضو هیئت علمی و مدرس گروه معماری دانشکده هنر و دانشگاه تربیت مدرس (1381) رئیس دانشکده گروه معماری دانشکده هنر و دانشگاه تربیت مدرس (1375) رئیس دانشگاه هنر تهران(1383) عضویت کمیته ملی میراث طبیعی و فرهنگی کمیسیون ملی یونسکو (1382) دانلود: [Hidden Content] Radio808-70-(Saze808.com)_0.part4.rar Radio808-70-(Saze808.com)_0.part3.rar Radio808-70-(Saze808.com)_0.part1.rar Radio808-70-(Saze808.com)_0.part2.rar
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    منظور شما از ثابت پیچشی اگر J یعنی همان ممان اینرسی قطبی است بله شامل قضیه محورهای موازی میشود که دراینجا میزان اضافه شدن آن برابر حاصلضرب مساحت مقطع در فاصله نقطه مورد تا مرکز برش مقطع به توان دوم دارد.
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    Aeration in Bottom Outlet Conduits of Dams for Prevention of Cavitation Original Article, B35 Kolachian R, Abbaspour A, Salmasi F. Journal. Civil Eng. Urban. 2(5): 196-201. 2012. ABSTRACT:The more necessity of human communities to water resources demand leads to establishing and development of high dams and hydraulic structures with high capacities. With increasing in dam height, the water velocity in bottom outlet conduits increases. In the case of decreasing of local pressure due to sudden change in flow area or the passage slope the possibility of cavitation occurrence through the structure increases. Experiences showed that the flow aeration can decrease the risk of cavitation damages effectively. The investigations of flow characteristics by numerical methods along with physical hydraulic models can be effective in choosing the best choice for aeration and also decrease extra cost and time of physical modelling. In this research, first, the cavitation occurrence in bottom outlet of Sefidroud dam was evaluated in different gate openings by Fluent software in 3D mode and then after the comparison results of numerical and physical model, a method for aeration of this structure consist of aerator ramps on floor and side walls of conduit is suggested and investigated by numerical model. For this purpose the VOF model was used for flow simulation in tunnel and the water surface profile, mean velocity, static pressure and cavitation index were investigated before and after aeration. The results showed the relative capability of numerical models in flow simulation in bottom outlet conduit of dam and improving the flow conditions after aeration. Keywords:Aeration, Bottom outlet conduit, Cavitation, Fluent منبع: [Hidden Content] دانلود: [Hidden Content] JCEU, B 35 196-201.pdf
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    Investigating the Distribution and Orientation of Steel Fiber Reinforced Concrete Original Article, B34 Zandi Y. Journal. Civil Eng. Urban. 2(5): 191-195. 2012. ABSTRACT:The distribution functions of fiber location variables were investigated that can be used to produce an analytic model to predict the mechanical properties of SFRC. Considering the effect of surrounding boundaries and distribution function, theoretical expressions were derived for the number of fibers per unit cross sectional area in SFRC. A comparison between empirical results and the theory were done to confirm the analytical results. Fibers are usually used in concrete to control cracking due to both plastic shrinkage and drying shrinkage. The amount of fibers added to a concrete mix is expressed as a percentage of the total volume of the composite (concrete and fibers), termed volume fraction (Vf). Vf typically ranges from 0.1 to 3%. Fibers with a non-circular cross section use an equivalent diameter for the calculation of aspect ratio. Keywords:steel fiber reinforced concrete; steel fibers; vibration, distribution function. منبع: [Hidden Content] دانلود: [Hidden Content],%20B%2034%20191-195.pdf JCEU, B 34 191-195.pdf
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    Sensitivity Analysis of Movable Bed Roughness Formula in Sandy Rivers Original Article, B33 Fuladipanah M,Majediasl M. Journal. Civil Eng. Urban. 2(5): 187-190. 2012. ABSTRACT:Sensitivity analysis as a technique is applied to determine influential input factors on model output. Variance-based sensitivity analysis method has more application compared to other methods because of including linear and non-linear models. In this paper, van Rijn’s movable bed roughness formula was selected to evaluation because of its reasonable results in sandy rivers. This equation contains four variables as: flow depth, sediment size, Bed form height and Bed form length. These variable’s importance was determined using the first order of Fourier Amplitude Sensitivity Test. Sensitivity index was applied to evaluate importance of factors. The first order FAST based sensitivity indices test, explain 90% of the total variance that is indicating acceptance criteria of FAST application. More value of this index is indicating more important variable. Results show that bed form height, bed form length, sediment size and flow depth are more influential factors with sensitivity index: 32%, 24%, 19% and 15% respectively. Keywords:Sensitivity Analysis, Variance, Movable bed roughness formula, Sandy River. منبع: [Hidden Content] دانلود: [Hidden Content],%20B%2033%20187-190.pdf JCEU, B 33 187-190.pdf
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    Strengthening of Steel Slab-On-Girder Bridges by Increasing Torsional Stiffness, Case Study: Karkhe Bridge Original Article, B32 Gharighoran A, Rafizadeh A. Journal. Civil Eng. Urban. 2(5): 182-186. 2012. ABSTRACT:A field investigation is conducted to strengthening of Karkhe Bridge with type of steel slab-girder in Khouzestan, Iran that it was damaged due to unusual loading and had been extra vibration. In the first, two types of truck are assigned that one of them has loading of Iranian code (40-ton-truck), and other has unusual loading (90-ton-truck) that used in field for transportation of materials. In the next step, this bridge is analyzed by finite element method under these two types of loading, and load distribution factors for different modes are determined. According to these factors, flexural and torsional moment and also displacements of bridge are calculated. In order to strengthening of bridge, fin sections are used to increasing the flexural stiffness for girders, and lateral bracings are used to increasing the torsional stiffness. Finally, results of analysis after strengthening of structure are compared with results before strengthening, that it shows improving in distribution of load between girders and decrease of displacements for bridge deck. Keywords:Steel Bridge, Slab-on-girder, Torsional stiffness, Unusual load, Finite element method منبع: [Hidden Content] دانلود: [Hidden Content] JCEU---B 32 182-186.pdf
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    Optimization of Clay Core Dimensions in Earth Fill Dams Using Particle Swarm Algorithm Original Article, B31 Roshani E, Farsadizadeh D. Journal. Civil Eng. Urban. 2(5): 176-181. 2012. ABSTRACT: The flow rate from earth fill dam body mainly depends on the dimensions and characteristics of the clay core. Thus, finding the optimized dimensions for clay core in non-homogeneous earth fill dam is essential. In order to decrease water loss, the clay core should be expanded this leads to dramatic increment in construction volume and costs. The novelty of this issue could be expressed as an optimization material in which the total cost of lost water and earthwork should be minimized. The method serves us a simpler and an accurate solution for an earth fill dam to be in optimised dimensions. The objective function is consisting of two parts. The first part is to calculate the water seepage volume through the dam core with a combination of finite element method and artificial neural network (ANN) and the second part encounters the costs regarding to the volume of earth works. Finally the best answer from the economical view will be chosen according to the amount of seepage and core volume. Since calculating water seepage through soil using finite element method is time consuming, first a combination of 600 different potential shapes of the core has been modelled by finite element and then the result have been used to train an artificial neural network. Comparing this model with linear and logarithmic regression models proved that ANN evaluates water flow rate with more precession. Output data, including flow rate, entered to the particle swarm optimization (PSO) algorithm and the optimized dimensions were achieved. The proposed model for optimizing the clay core dimension can be applied for non-homogeneous earth fill dams with impervious foundation. Allavian earth fill dam was chosen to show the benefit of using the proposed optimization method in a real world case study. The results indicated that the construction cost could be dramatically less than what has been already spent on the case study. Keywords:Optimization, Clay core, Artificial neural network, Particle swarm optimization منبع: [Hidden Content] دانلود: [Hidden Content],%20B%2031%20176-181.pdf JCEU, B 31 176-181.pdf
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    Effects of a Locally Sourced Water Reducing/Retarding Admixture on Concrete Original Article, B30 Oladiran A, Aderinlewo, Tanimola M. Journal. Civil Eng. Urban. 2(5): 170-175. 2012. ABSTRACT:The results of experiments to determine the effects of a water reducing/retarding admixture locally sourced from orange tree leaves on concrete are presented in this paper. The admixture was added to the concrete mix in percentages of 1, 2, 5, 10 and 15 by weight of cement. The results showed that the workability of the mix improved while the water cement ratio reduced gradually as the admixture content was increased from 1% to 15%. Cube crushing tests performed showed that the 28th day compressive strengths of the concrete increased considerably as the admixture content increased from 1% to2% up to 5% beyond that of the control. Thereafter, the compressive strengths dropped at 10% and 15% admixture contents. The percentage increase in compressive strengths of the concrete with 1%, 2% and 5% admixture contents were 6.58%, 14.07% and 23.53% respectively above that of the control. Keywords:water reducing, retarding, admixture, workability, crushing tests, compressive strengths. منبع: [Hidden Content] دانلود: [Hidden Content],B%2030%20Effects%20of%20a%20Locally%20Sourced%20Water%20Reducing-Retarding%20Admixture%20on%20Concrete.pdf JCEU ,B 30 Effects of a Locally Sourced Water Reducing-Retarding Admixture on Concrete.pdf
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    Gene Expression Programming for Prediction of Flow Discharge in Compound Channels Oiginal Article, B29 Zahiri A, Eghbali P. J. Civil Eng. Urban. 2(4): 164-169. 2012. ABSTRACT:There are many studies on the hydraulic calculation of steady uniform flows in compound open channels. Based on these studies, various methods have been developed with different assumptions. In general, these methods either have long computations or need numerical solution of differential equations. Furthermore, their accuracy for all compound channels with different geometric and hydraulic conditions may not be guaranteed. In this paper, to overcome with these limitations, a new simple and dimensionless equation has been proposed based on gene-expression programming (GEP), which is an extension to genetic programming (GP). In this equation only three parameters (e.g. depth ratio, coherence and ratio of computed total flow discharge to bankful discharge) have been used to simplify its applications for hydraulic and river engineers. By compiling 394 stage-discharge data from laboratories and fields of 30 compound channels, this new equation has been applied to estimate the flow conveyance capacity. The proposed GEP approach gives satisfactory results (R2 = 0.98 and RMSE = 0.32) compared to traditional method (VDCM) with R2 = 0.69 and RMSE = 1.72 for flow discharge computations. Keywords:Compound Channels, Gene Expression Programming, Stage-Discharge Curve. منبع: [Hidden Content] دانلود: [Hidden Content],%20B29.pdf JCEU, B29.pdf
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    Design of Stilling Basins using Artificial Roughness Oiginal Article, B28 Nasr Esfahani MJ, Shafai Bejestan M. J. Civil Eng. Urban. 2(4): 159-163. 2012. ABSTRACT: Various types of hydraulic jumps have been analyzed experimentally, theoretically and numerically and the results are available in the literature. In this paper, very large series of experimental data are collected and used to develop a design equation for the optimal stilling basin with cube roughness elements. The experiments were conducted in a wide laboratory flume to study the effect of roughness parameters on the length of the roughened floor. Roughness elements are distributed in a staggered way. Two different heights of roughness were considered. The results of this study show the attractiveness of rough beds for energy dissipation below hydraulic structures. It was found that increasing the roughness length doesn’t make great difference in energy loss, but the roughness height is very impressive at the hydraulic jump characteristics. Compared with the smooth bed, the rough beds decrease the relative the relative jump sequent depth by 5.3-12.76%. The axial velocity profiles at different sections in the jump were found to be similar, with some differences from the Profile of the simple plane wall jet. Keywords:Hydraulic jump, Abrupt Drop, Rough beds منبع: [Hidden Content] دانلود: [Hidden Content],%20B28.pdf JCEU, B28.pdf
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    Land Use Change Detection of Maragheh City and Its Implication for Agricultural Area and the Orchards by Using the Multi-Temporal Satellite Imagery Oiginal Article, B27 Azari M, Ahadnejad Reveshty M, Kamelifar MJ, Ranjbarnia B. J. Civil Eng. Urban. 2(4): 154-158. 2012. ABSTRACT:Urban growth is one of the complex behaviors which the cities show over passing time and in order to meet the needs of living spaces, working spaces, shopping areas, etc. of its residents. Sometimes this behavior is in contrast with agricultural areas and it causes destruction of this areas. Maraghe is one of the cities whose urban growth process has been in contrast to agricultural areas and this contrast has caused the destruction of agricultural areas and orchards at the price of urban built-up areas. At this paper, the changes of agricultural areas and especially the orchards of Maraghe to built-up areas have been shown between 1984-2011 by using the Landsat TM & ETM­+ imagery and GIS. Thus, the images have been classified using Fuzzy ARTMAP method and consequently the process of land use changes have been extracted by utilization of Cross correlation. The results of paper show that about 591 hectares of agricultural areas has been changed to built-up areas in the period of 1984-2011 (hence 45 percent of entire land use changes); 207 hectares of agricultural areas and 16 percent of entire changes to built-up areas consists of orchards. In addition to having ecological effects, Maraghe orchards are one of the indicators of the urban landscape and identity. Keywords:Land use change, city of Maraghe, agricultural areas, RS & GIS. منبع: [Hidden Content] دانلود: [Hidden Content],%20B27,August%2027.pdf JCEU, B27,August 27.pdf
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    Wavelet-Based Method for Damage Detection of Nonlinear Structures Oiginal Article, B26 Mohammadpour Lima M, Ghodrati Amiri Gh, Bagheri A. J. Civil Eng. Urban. 2(4): 149-153. 2012. ABSTRACT: In the recent decades, damage detection and system identification methods that are based on wavelet analysis and signal processing for structural health monitoring of engineering structures have been developed. Analyses that are based on time-frequency domain provide more information about non-stationary signals. In this paper, an effective method is presented for damage detection of nonlinear structure based on restoring force by using wavelet transform. Two nonlinear frame models are used for simulation of the real condition of structures and restoring force response is calculated by Runge-Kutta method. The results for damage detection by the proposed method in the structures show the reliability of the method. Keywords:Damage Detection, Nonlinear Structure, Restoring Force, Wavelet Transform. منبع: [Hidden Content] دانلود: [Hidden Content]-,%20B26.pdf JCEU-, B26.pdf
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    Cost Implication of Mitigating the Effect of Clay/Silt Content of Sand on Concrete Compressive Strength Oiginal Article, B25 Olanitori LM. J. Civil Eng. Urban. 2(4): 143-148. 2012. ABSTRACT: In Nigeria, reinforced concrete is one of the major building materials been used in the construction of buildings. In the specification of concrete, prescribed mix is normally used. However, tests carried out on different batches of concrete produced, using prescribed mix 1:2:4 of concrete show that the concrete did not acquire the 20N/mm2 expected strength at the age of 28 days. Depending on the type of sand used for the production of the concrete, the acquired strength after 28 days is between 25% and 60% of the expected strength. This reduction in strength will ultimately affect the functionality and durability of structure constructed from such concrete. To mitigate the effect of clay/silt content of sand, the sand can be washed free of clay/silt or the cement is increased in proportion to the percentage content of clay/silt in the sand. Since the mitigation of the clay/silt content of sand on concrete strength comes with extra cost, there is need to determine this cost in other to be able to build effective and safe structures. The author evaluates the cost implication of mitigating this reduction effect of the type of sand used on concrete strength. The extra cost incurred in the production of 1m3 of concrete (using mix ratio 1:2:4) in terms of washing the sand free of clay/silt is 22.5%, while that of cement increment is between 2.22% and 27.75% depending on the percentage of clay/silt content of sand. Mathematical models, which can be used to estimate the cost implication of this mitigation, are derived. Keywords:Reinforcement, Concrete, Sand, Silt, Strength منبع: [Hidden Content] دانلود: [Hidden Content],%20B25.pdf JCEU, B25.pdf
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    Effects of Urbanization on Stream Channels Original Article, B24 Biabanaki M, Tabatabaei Naeini A, Eslamian S. J. Civil Eng. Urban. 2(4): 136-142. 2012. ABSTRACT:In response to urbanization, stream channels can undergo substantial changes, especially if channel stabilization measures are not instituted in the early stages of urbanization. Urbanization causes (1) significant increases in peak discharges, total runoff volume, and frequency of bank-full discharges; (2) the steepening of channel slopes if and where natural channels are straightened to accommodate new development; (3) reduction in sediment bed load from fully developed areas; and (4) eroding and degrading natural channels. These factors, in combination, create conditions that are conducive to channel instability—widening (erosion) and deepening (degradation) in most reaches and debris and sediment accumulation (aggradation) in others. To fully evaluate the proper channel morphological processes when undertaking a basic design or protective measure project, it is necessary to have some knowledge of channel stability concepts. The normal objective of channel stability evaluation is identification of principal channel hydraulic parameters influencing the stability of the channel. After identifying these parameters under existing channel conditions, the values of these parameters under future conditions are estimated. For areas undergoing urbanization, one of the most important changes is an increase in the volume, frequency, and flow rates of water in main channels. Stability analysis is then performed based on hydraulic parameters for anticipated future conditions, and stabilization measures are planned to minimize potential channel erosion under future conditions. There are a number of quantitative methods of channel stability analysis available to the designer including allowable velocity methods, tractive force calculations, and Leopold channel configuration relationships, among others. The hallmark of urbanization is increased imperviousness. Planning of a major drainage system must account for changes in hydrology, hydraulics, and channel stability that urbanization produces. As a result, the design of the major drainage system must be based on fully urbanized conditions to assure adequate capacity for conveyance of the major (e.g., 100-year) flood event. It is also important to recognize that the higher sediment loads during the process of urbanization (during construction) may shift the channel toward an equilibrium state that is different from the desired stable channel balance for the urbanized basin. Keywords: Stream Channels; Major Drainage; Initial Drainage; Urbanization منبع: [Hidden Content] دانلود: [Hidden Content],%20B24.pdf JCEU, B24.pdf
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    Material-Based Ultimate Moment of Resistance of a Rectangular Concrete Section Original Article, B23 Joseph Afolayan O, Stephen Alabi A, Lekan Olanitori M. J. Civil Eng. Urban. 2(4): 131-135. 2012. ABSTRACT:The incessant collapse of buildings in Nigeria in recent years has been a major concern. This paper addresses one of the major possible causes of building collapse. The minimum compressive strength of concrete using pit-sand as a fine aggregate in Akure, Nigeria was statistically estimated. On the basis of the estimated nominal concrete strength, an implied ultimate moment of resistance of singly reinforced concrete rectangular sections is proposed. The proposal shows that the recommended resistance of concrete given by BS8110 (1997) may be reduced by as much as 50% in order to accommodate the minimum concrete strength for a 1:2:4 mix. A numerical design example based on the proposal showed the necessity of additional compressive reinforcement to justify the use of the current BS 8110 (1997) requirement if Akure pit-sand must be used as fine aggregate. Keywords:Pit-sand, Concrete, Compressive Strength, implied Ultimate Moment of Resistance. منبع: [Hidden Content] دانلود: [Hidden Content],%20B23.pdf JCEU, B23.pdf
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    راهنماي نحوه تهيه و اعلام پروژه طرح هاي تملك دارايي هاي سرمايه اي شماره ضابطه : 94-207904 تاریخ ابلاغ: 1394/08/16 منبع: [Hidden Content] دانلود: جدول راهنماي نحوه تهيه و اعلام پروژه طرح هاي تملك دارايي هاي سرمايه اي [Hidden Content] راهنماي نحوه تهيه و اعلام پروژه طرح هاي تملك دارايي هاي سرمايه اي [Hidden Content] 94-207904.pdf Jadval-Pishnahad-Proujeh-94-207904.rar
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    راهنماي تامين منابع مالي با استفاده از منابع بانك هاي توسعه اسلامي، جهاني و اكو (متناسب با پروژه هاي صنعت آب و آبفا) نشریه شماره 685 World Bank, IDB. ECO Guideline تاریخ اجرا: 1394/08/20 منبع: [Hidden Content] دانلود در دو بخش: بخش اول: [Hidden Content] بخش دوم: [Hidden Content] Development Banks Guide.part5.rar Development Banks Guide.part6.rar Development Banks Guide.part4.rar Development Banks Guide.part3.rar Development Banks Guide.part2.rar Development Banks Guide.part1.rar
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    راهنماي پادسيل سازي ( نشریه شماره 681) Flood Proofing Guideline تاریخ اجرا: 1395/01/01 منبع: [Hidden Content] دانلود: [Hidden Content] code681.pdf
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    Transferring of Limited Rights Model (TLRM) with the highest priority in the Theory of Development Plans Original Article, B22 Kocalar AC. Journal. Civil Eng. Urban. 2(3): 122-130. 2012. ABSTRACT:In this study, transferring of limited rights model (TLRM) is proposed as an innovative implementation instrument for development plans in which its coverage area with theoretical and practical approaches is a holistic structure in relation with different disciplines and so widely. The model can be used with protected areas easily or together with preventive steps in related to the emergency situations such as the natural disasters. This model is also kept its validation in cultural, historical, urban, archeological, social and natural assets, and also cost, forest, meadow, sheep, thicket, heath and national parks, at the same time protects quag, underground, surface water, dams, drainage or water basins besides disasters, forest fire, flood, avalanche, disasters at first or later. The proposed model can be utilized for the aim of public service, order and interest in the development planning studies and applications, in the urban conservation, renewal and regeneration, in the real estate's utilization of individual and corporate ownership, in the process of making laws, the regulations and the decisions since 1980, as a result of the planning qualified as a rule of transaction. Keywords: Development plans implementation instrument, Transfer property and development rights, Transfer rights in the restricted immovable, Abstract and concrete allowances, Local authorities, TLRM, Property owner without land shares. منبع: [Hidden Content] دانلود: [Hidden Content],%20122-130.pdf JCEU-B22, 122-130.pdf
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    Application of Bed Sill to Control Scouring Around Cylindrical Bridge Piers Original Article, B21 Razi S, Salmasi F, Hosseinzadeh Dalir A and Farsadizaeh D. Journal. Civil Eng. Urban. 2(3): 115-121. 2012. ABSTRACT:Results are presented from laboratory experiments to investigate the effectiveness of bed sills in reduction of scour depth at cylindrical piers under clear water flow condition. The experiments were performed in a flume with 6.0-m-long, 0.8-m-wide, 0.5-m-deep and zero longitudinal slope. During experiments a bed sill with 10-mm-thick, 0.6-m-length and 0.15-m-height equal to sand bed deep was used. The scour depth in front of the piers becomes negligible as the bed sill placed upstream the piers, but it is to be noted that the scour downstream of the piers in this case is more than when the bed sill placed the downstream of the piers, i.e., risk of reduction of bed surface because of local scour and particularly general scour will be increased as the bed sill placed upstream the piers. The best location for the bed sill is suggested downstream and about snap of the piers. In this case the reduction percent of scour depth in front of the piers is about 29% in the best configuration. Keywords: Scouring, Cylindrical Piers, Bed sill, Scour reduction منبع: [Hidden Content] دانلود: [Hidden Content],%20115-121,%202012.pdf JCEU-B21, 115-121, 2012.pdf
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    Vertical Sluice Gate Discharge Coefficient Original Article, B20 Nasehi Oskuyi N, Salmasi F. Journal. Civil Eng. Urban. 2(3): 108-114. 2012. ABSTRACT:Sluice gates are widely used for flow control and discharge measurement in irrigation and drainage channels. Their discharge coefficient depends on geometric and hydraulic parameters. Errors are inevitable when their values are abstracted from empirical curves for a range of reasons including the resolution of the graphs, judgments in reading the values, the need for their digital values at the computational stages. This study develops two equations, linear and nonlinear, to determine discharge coefficient by using dimensional analysis and linear and nonlinear regression analysis, for both free and submerged flow conditions. A total of 5200 data point was generated, which involved different effective hydraulic parameters. The study also included the results of the past studies carried out by different investigators concerning sluice gate discharge coefficient determination for comparison purposes. The performance of the nonlinear equation improves in comparison with the linear equation. All numerical computations were carried out by Wolfram Mathematica v.6 software. Keywords: Discharge coefficient, free flow, multiple regressing, sluice gate, submerged flow منبع: [Hidden Content] دانلود: [Hidden Content],%20108-114,%202012.pdf JCEU-B20, 108-114, 2012.pdf
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    Weep Hole and Cut-off Effect in Decreasing of Uplift Pressure. (Case Study: Yusefkand Mahabad Diversion Dam) Original Article, B19 Azizi S, Salmasi F, Abbaspour A and Arvanaghi H. Journal. Civil Eng. Urban. 2(3): 102-107. 2012. ABSTRACT: In order to have economic designs to reduce uplift pressure in hydraulic structures like diversion dams and concrete gravity dams, so many methods have been proposed that the most important include construction of horizontal aprons/cutoff walls in upstream and downstream of the dam and weep holes in the downstream or proper place between the two cutoffs. The effect of weep holes and cutoff on uplift pressure is the main goal of this study. This study focuses on Yusufkand Mahabad diversion dam in IRAN, by simulation it in Seep/W software. Effect of weep holes location and different depth of the dam cutoff walls on uplift pressure and on exit hydraulic gradient is investigated. Results show that upstream cutoff with 8 meter depth decreases uplift force about 63% and decreases exit gradient 79% respect to without cutoff case. Installing weep hole in downstream stilling basin decreases uplift force 8% and decreases exit gradient 74% more than without weep hole. Based on this research, design of diversion dams can be carry out by minimizing concrete costs and hence become economical design. Keywords: Diversion dam, uplift pressure, exit hydraulic gradient, cutoff wall, weep hole. منبع: [Hidden Content] دانلود: [Hidden Content],%20B19,%20102-107,%202012.pdf JCEU, B19, 102-107, 2012.pdf
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    The application of golden proportion in the façades and ornaments of quadruple vaulted porticos of Jami mosque in Isfahan,Iran Oiginal Article, B18 Mahdipour M, Mahdizadeh Saradj F. Journal. Civil Eng. Uan. 2(3): 97-101. 2012. ABSTRACT:Various investigations have been carried out about the Jami mosque of Isfahan before and each of them considered analyzing a part of assets of this magnificent arte fact. A part of these studies focused on the building fabric and resulted in the pathology of this building. A group of published works have been concentrated on the architectural styles of the building and its evolution through the various reigns of Iranian kings. Arthur pope and Andre Godard analyzed the shapes and styles of the building before and after Islam. Recent researches have also been carried out more about the brick laying systems of vaults, brick ornaments, tile works and plastering. However not enough research has been done about the aesthetic aspects and using golden proportion in the facades and quadruple vaulted porticos of this mosque. A comprehensive study about the golden ratio and golden proportion which is rooted in the Fibonacci series has led towards a geometrical shape which has been used as a standard measure to check the existence of any employment of golden ratio. Placing this standard shape over the arches of vaults in facades according to the scale of the maps revealed the usage of golden proportion in them. Architects and master builders of this mosque were aware of the adjunctions to the building throughout history and were trying to create coordination and harmony between various parts by using proportion systems. Keywords: proportion, golden proportion, Jami mosque of Isfahan, portico, façade منبع: [Hidden Content] دانلود: [Hidden Content], 2012.pdf JCEU, B18, 97-101, 2012.pdf
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    Prioritizing the Sustainable Development Components and its Role in the improvement of Urban Effete Fabrics with group Analytical Hierarchy Process (AHP): A Central Part of Isfahan City Case Study Original Article, B16 Rashidi Ebrahim Hesari A, Mousavi SCh, Bahmand D, Samadi R. Journal. Civil Eng. Urban. 2(3): 86-91. 2012. ABSTRACT: Effete fabrics are the confines of urban realms that are in the city structures in dealing with some negative features. These neighborhoods are suffering from the kinds of shortages and problems such as exterior and physical exhaustions, poor urban infrastructures and services, social felonies and cultural problems and the types of economic problems. Despite all the weaknesses and shortcomings, these fabrics are part of the cities and there are many residents living in. It seems that given the scope and severity of the problems that beset these contexts, the most comprehensive approach adopted for dealing with shortcomings and deficiencies in effete fabrics is a participatory approach with sustainable purposes and development. Isfahan is considered the biggest historical town in Iran that an extensive part of its old context is affected with effeteness. This study aims to identify and ranking the sustainable development components influencing on the economic, social and physical improvements and the condition of access to improve and revive the effete fabrics of Isfahan city using hierarchical analysis method (AHP) and also using Expert Choice software. Although an effete context is an unavoidable result in city environment, these problems can be reduced or resolved with efficient policy. Having been analyzed and ranked the factors using collected comments and Expert Choice, the obtained results indicate that economic factors with 0.131 weights have the most effect on the improvement of effete city fabrics and social factors with 0.208 weights and environmental factors with 0.131 weights are the next priorities. Keywords: Effete context, Sustainable development, Group Analytical Hierarchy Process, Isfahan city منبع: [Hidden Content] دانلود: [Hidden Content], 86-91.pdf JCEU-B16, 86-91.pdf
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    Assessment of the Topological Properties of Akure Road Network Original Article, B17 Oluwajana S, Owolabi A, Aderinlewo O, Croope S. Journal. Civil Eng. Urban. 2(3): 92-96. 2012. ABSTRACT: This paper assesses the topological properties of Akure road network using graph theory. Three 1,609-square meters of different urban street sections were sampled from Akure road network map and developed into graphs using the primal approach. The resulting graphs were then described by their adjacency matrices. Investigation into the topological properties of the resulting graphs revealed that the three networks produced possessed small average clustering coefficients of 0.007, 0.016, and 0.026 and small average path lengths of 0.066, 0.088 and 0.062. The paths lengths obtained deviated from one obtained when it was assumed to be randomized. The degree distribution obtained over the networks could not be approximated using either binomial or Poisson distribution. Further investigation revealed Akure road network exhibited a power law degree distribution. Keywords: Network, graph theory, topology, clustering coefficient, path length, degree distribution, scale free network. منبع: [Hidden Content] دانلود: [Hidden Content],%2092-96.pdf JCEU.-B17, 92-96.pdf

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