JOURNAL OF TRANSPORTATION RESEARCH
Year:2015 | Volume:12 | Issue:3 (44)|Papers Count:9

Annual about 150 thousand tons of old tire is produced in Iran. There is no possibility to dispose of the waste in the environment. Because tire is decomposition with low speed and makes mush pollution in the environment, thus optimal use of these wastes has become a necessary. In this study, tensile, flexural and compressive strength of 28-day and 70-day compressive strength of concrete is studied in the environment of the acid and alkaline. Thus, it is considered the percentage of ash tire by weight relative to the weight of the cement equivalent to 1%, 2%, 3%, and the water – cement ratio equal to 40%, 45% and 50%. Experimental results show that the addition of tire powder, concretes shotcrete improved mechanical properties including compressive strength, tensile strength and bending strength. Also, the mechanical strength of shotcrete containing tire powder is much more than the corresponding conventional shotcrete containing Nano-silica.

Rail accident statistics show that over a wide range of hazards and risks that threaten the country's rail industry And because human beings are involved in the construction and operation of most systems, this is the role of humans in systems analysis, is considered a critical role. Due to the important part of any organization's human capital, under the supervision and control of the force, It is necessary to maintain safety organization guardians competence in guiding behavior and control conditions were concentrated. So the aim of this study is identifying the most important components of competency model. According to result of this study, Technical skills of human resource in railway industry is the most important component in addition, leadership and autority are the next priorities.

Despite the traffic increases at the World airports, little works have been done to improve vehicles and airplanes services, increase efficiency and decrease service automobile voluminous of large number. With GIS abilities, airport managers would like using its potential for development and management of airports. So new issue in GIS is formed with AGIS title to study GIS applications in airport as wide and corporation all world airports and GIS specialists. This paper presents an application of GIS analyses in airport field. The main innovation of this research is offline spatiotemporal data analysis and introducing an efficient algorithm for service automobiles allocation optimization with reduction in departure time deferment constraint. Allocation has been done by considering the aircraft push and tow required time and its distance to a service car. In this proposed solution servicing operation optimizes with considering two situations: one that service car returns to its Equipment Parking Area or EPA when delivering service and in another situation service car parks in Equipment Staging Area or ESA. Numerical results of using proposed method in Mehrabad international airport indicate in both situations, departure delay is lesser than usual method. Outcomes of minimizing service cars are: traffic reduction, increase management efficiency, decrease hazards due to large number of service cars and increase safety in airport field.

Every year we spend a lot of cost for constructing and maintaining roads, these costs are significantly related to the type of the pavement and its fundamental materials. Iranians usually use the flexible pavement which contains the asphaltic overlay and the granular base and sub grade, while we can pay more attention to the rigid and the composite pavement for using in our highways too.In this study a flexible pavement and a composite one for the Qazvin - Zanjan freeway by AASHTO method has designed and their initial costs and whole life costs has compared with each other. It has shown that the cost of constructing composite pavement is more than the flexible one but because of the cost-effective maintenance, its whole life cost is less than the whole life cost of traditional flexible pavement. Also the composite pavement has some technical advantages such as its high fatigue resistance, low deformation and high friction, though, composite systems are potentially more prone to other distresses, such as reflective cracking and rutting within the HMA layer. Premium HMA surfaces and/or reflective cracking mitigation techniques may be required to mitigate these potential problems

Railway as a transportation system is an important issue because of some advantages such as crowed of people, transportability, environmental impacts, energy saving and tourism attraction. In this issue determining suitable rail stations is necessity because of noticeable effects on economic, social, political and cultural applications. So the aim of this paper is to survey the condition of rail stations in Khorasan Razavi case study to estimate locations and improve existed positions for development. For this purpose, geospatial information system (GIS) as aflexible framework is used to program, manage and decide on spatial data for specifying best locations. Continually the related data included crowding center, industrial and commercial infrastructures are controlled and prepared to enter GIS an MCDM (TOPSIS & AHP) models. The results of the implementation show that Marzdaran is the worst station by rank of 22 and the best stations are located near big cities. In addition, evaluation of AHP and TOPSIS presents that Neghab station has the highest modification among all others.

Considering the effects of transportation on citizens’ lives and the large amount of needed fund requires high accuracy in prioritization of urban transportation development scenarios on decision making step. Any kind of error on this stage may cause a non-optimum decision and consequently imposed considerable costs on the public. In this research the Network Analytic Process is selected as the superior methodology for solving the mentioned problem. This is based on the investigation of existing studies relating the operational approaches on public transportation development scenarios. Afterwards a newly approach named "3-stages algorithm" is introduced in order to overcome some potential computational errors associated with network analysis process. In application of this algorithm, considering the key role of evaluation criteria determination and a comprehensive investigation on studies done on public transportation evaluation, degree of attention on each of aforementioned criteria and applying a one stage brain storming, a set of criteria were selected based on the opinions of urban transportation experts. The modified network analysis process is suggested for the assessment and prioritization of urban transportation development scenarios as the result of this research.

Transportation problem and its cost is one of the major problems facing all countries. To meet the demand of different parts of the country for oil products every year, a big capacity of these products is carried by the transport system of the country. These demands are realized from domestic refineries production and import sources. The problem is how to carry these products from refineries and import sources to different parts of the country. So, this paper optimizes the transmission network of gas oil of entry points to consumption Centers, by using the transshipment model with minimize transport expenses. Considering place the research covers the whole country and considering time the presented model fits the transport system of 1390. Optimum results show 63% in cost of saving gas oil distribution expense by using 78% of the pipeline.

Stripping and permanent deformation are two major modes of distress in asphaltic pavements. One of the measures to control these distresses is using additives, and, a variety of additives has been studied. In this research, the effect of two types of fiber on the moisture damage and permanent deformation properties of asphaltic concrete has been investigated.38 mm long Polyester and 120 mm long polyacrylic fibers in different contents have been added to a typical asphaltic concrete and the permanent deformation behavior has been investigated by creep tests, and the moisture damage has been investigated by indirect tensile test in dry and saturated conditions. The results show that the fibers improve the permanent deformation behavior of asphalt concrete. However, while the polyester fibers improve the moisture damage property of the mixture, the polyacrylic fibers decreases the ratio of the saturated to dry indirect tensile strength of the mixture.