International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
SENSITIVITY ANALYSIS OF STRATEGIC INDICATORS IN PRICING MODEL FOR INTERCITY PASSENGER SERVICE
55
64
EN
AFANDIZADEH SH.,
ZOGHI H.
Since Road transportation accounts for a large portion of total displaced passengers of Different types it is the most important mode of passenger services in Iran. The costs considered are depreciation, investment, insurance, tax, fuel, tires, main repairs, unexpected repairs, oil filter break shoe. Lubrication, batteries, commission, wages and other miscellaneous costs. These are classified into two categories of fixed and variable costs that it-ere analyzed. The data used is obtained, from the Iranian passenger transportation co- operatives based on their real costs in Fear 2002 . The methodology of determination rate of return and Passenger Transportation Price are described and these parameters are calculated. In this paper, a price model based on the economic techniques and sensitlvtfx. Analysis is presented for operators and managers. Pricing model of passenger service is prepared by the authors by the name of Development of Pricing Model of passenger Services in Intercity Roads . This research is pointing to Model Sensivity Analysis Dependent on Various Indicators.
International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
DEVELOPING AN OPTIMUM INCOME CREATING MODEL FOR PROFIT MAKING OF AIR TRANSPORTATION SYSTEM
65
71
EN
SAFFAR ZADEH M.
BAHRAMIAN H.R.
In this paper an attempt is made to develop a model to increase profit-making in air transportation system taking into consideration of the most important problems encountering the system. Utilizing the outcomes of this model, general policies for investing capital to carne out profit-making projects can be recognized.In the presented model the least squares and non-linear optimization methods have been utilized to recognize unknown quantities. In addition, to simplify the developed model and obtain numerical results, the available potential for increasing profit-making in the system has fallen into three major categories. Moreover, profit-making sources have been classified in five distinguished sections.Since recognizing the utilized coefficients in the model claims extensive studies, in most of the cases, the air transport experts and authorities comments have been taken into consideration and an attempt has been made to adapt these coefficients to real values.
International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
FREEZE AND THAW, AND ABRASION RESISTANCE OF STEEL FIBER REINFORCED CONCRETE (SFRC)
72
81
EN
A.R.
Khaloo
MOLAEE A.
An experimental program was carried out to investigate the behavior of steel, fiber reinforced concrete (SFRC) under abrasion and cycles of freeze and them. Compression and flexural tests were also performed in order to reach a comprehensive conclusion of the response. In total, over 200 specimens were tested The test variables included two concrete strength., (i. e., 28 MPa as Normal Strength (NSFRC) and 42 MPa as Medium Strength (MSFRC)), four volumetric percentage of fibers (i.e., 0%, 0,5%, 1.0% and 1.5%) and two fiber lengths (i.e.. 25mm and 35rnrn).Cube specimens were tested according to ASTM C6661n-ocedrrre B using 100 cycles of freeze and thaw. The Los Angeles test method for testing aggregate was used to evaluate the abrasion resistance of SFRC.Test results of1VSFRCptesertted improvements up to 39% and 32 % in cylindrical and cubic compressive strength, respectively. and 88�o in modulus of rupture, 57% in resistance against abrasion based oil weight loss and 40% against compressive strength reduction due to freeze and thaw cycles. The corresponding improvements for MSFRC were 18%, 16%, 48%, 53% and 46% respectively.Increase in cocncrete strength from 28 Ala to 42 MPa provided higher freeze and thaw and abrasion resistance than addition of 1.5% of steel fibers to the normal strength concrete matrix.
International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
PETROV GALERKIN FINITE ELEMENT ANALYSIS OF SHALLOW WATER EQUATIONS KAYVAN ASGHARI
82
91
EN
ASGHARI K.
The solution of shallow-water equation for a two-dimensional .simulation of overland /low for an actual watershed, is presented. The Petorv-Galerkin weighted residual method is used to overcome spurious oscillations inflow depth. For modeling overland flow over complex topography and variable surface, ct pre and postprocessor was developed to utilize the Triangulated Irregular Network (TIN) model and to generate finite element mesh. Close agreement of the model with measured data is obtained. This model can be used to better analyze the influence of varying surface roughness and topography on overland flow characteristics, including distribution of flow depth and velocity (is well as resulting hydrographs. Detailed spatial and temporal output parameters provide a basis fur further study of the patterns of soil erosion and evaluation of runoff natural slopes.
International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
LINEAR AND QUADRATIC LEAST SQUARES FINITE ELEMENT METHOD FOR INCOMPRESSIBLE FLUID FLOW
92
99
EN
AFSHAR M.H.
A least squares finite element method for the .solution of steady incompressible Navier Stokes equations is presented. The Navier-.Stocks equation is first recast into a system of first order partial differential equations with the velocitv. pressure and the vorticity as the main variables. Finite element discretization of the domain introduces a residual in the governing equation which is subsequently minimized in a least squares sense. The method so developed clearly. falls into the minimization category card hence circumventing the L.B.B. condition. Furthermore. the method produces symmetric positive definite matrices which makes the way for using more efficient iterative sobers. A Conjugate Gradient algorithm is, therefore, used for the solution of the resulting .system of linear algebraic equations. To improve the efficiency , of this iterative solver an incomplete Cholesky factorization of the stiffness matrix is used as ct pre-conditioner. Since the storage requirement of the Cholesky factor depends on the bandwidth of matrix. an effective algorithm for the reduction of this bandwidth has also been employed. The application of the method to solve cavity problem and .step flow with different Remolds number is presented to show the applicability of the method to solve practical flows of incompressible fluid The use of both linear and quadratic elements with selective reduced integration is also investigated and the results are presented.
International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
LABORATORY EVALUATION OF EROSION CHARACTERISTICS OF GROUT SUSPEN SIONS
100
113
EN
PAKBAZ M.C.
AHMADI C.
This research include, more than 400 erosion tests performed on coarse and fine grain suspension materials. The purpose of tests was to determine erosion characteristics of mixtures of different materials. Samples of the .same constituents in different groups were cured tit two different setting time of // and 16 !tours before they were subjected to the constant hydraulic heads of 20 and 40 cm for ct time period of 30 urinates. The amount of erosion was measured as the weight loss of the samples offer the test. /n general the lower setting tune and the higher hydraulic head for a large group of samples showed higher erosion. For uniform sand samples when the cement content was 60-70 % the percentage of erosion (PE) was below 2. For the mixture of sand-cement, with the clay content below, 20% the percentage of erosion was below 2 and it increased to 15.5 for the clan, content of 58dc. Die addition of bentonite in the soil-cement mixtures in general did not affect the erosion.
International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
STUDY ON LOCAL VOLUME CHANGE INDUCED BY MOISTURE FLOW IN UNSATURATED SAND-BENTONITE
114
122
EN
SHOOSHPASHA I.
This study was designed to investigate the local volume changes induced by swelling pressure in unsaturated stand-bentonite bused buffer material. A laboratory mixture of sodium bentonite (lilt/ well graded silica stool in equal proportion by do weight was used for moisture floss experiments in both ambient and elevated temperatures. Experimental results have shown that tit high water content locations within the tested specimens, the density was reduced by .3.57% from its initial values clue to swelling. The swelling pressure was calculated by 4 different models as a function of distance. The calculated results have indicated that the density distribution within the .specimen is affected by swelling potential distribution. The calculated swelling pressure values van as u function of water content, reaching I MPa at the source of water intake, i.e., at high water content :.one, and 2 MPa cot the heater .side, i.e., cot low water content .one.
International Journal of Civil Engineering
1735-0522
1
2
2003
12
1
PETROV GALERKIN FINITE ELEMENT ANALYSIS OF SHALLOW WATER EQUATIONS KAYVAN ASGHARI
114
122
EN
ASGHARI K.
The solution of shallow-water equation for a two-dimensional .simulation of overland /low for an actual watershed, is presented. The Petorv-Galerkin weighted residual method is used to overcome spurious oscillations inflow depth. For modeling overland flow over complex topography and variable surface, ct pre and postprocessor was developed to utilize the Triangulated Irregular Network (TIN) model and to generate finite element mesh. Close agreement of the model with measured data is obtained. This model can be used to better analyze the influence of varying surface roughness and topography on overland flow characteristics, including distribution of flow depth and velocity (is well as resulting hydrographs. Detailed spatial and temporal output parameters provide a basis fur further study of the patterns of soil erosion and evaluation of runoff natural slopes.