in this paper, we develop a freight transportation model for railway network considering hazmat transportation issue. in the transportation system considered, different customers can request for carrying hazmat and non- hazmat boxes. it is assumed that the sequence of the trains in the network is known. the objective is assigning the non-hazmat boxes and hazmat boxes to wagons of the trains so ...

Risk factors are generally defined and assigned to road networks, as constant measures in hazmat routing problems. In fact, they may be dynamic variables depending on traffic volume, weather and road condition, and drivers' behavior. In this research work, risk factors are defined as dynamic variables using the concept of chaos theory. The largest Lyapunov exponent is utilized to determine the ...

Most transportation infrastructures are exposed to a combination of mechanical and environmental loads. Normal concrete is brittle and tends to crack, resulting in a lack of durability and frequent repair needs. This paper describes an ultra ductile cementitious composite which is highly crack resistant, with a tensile strain capacity over three hundred times that of normal concrete. Apart from...

This research attempts to build a framework for determination of optimal routes for hazardous material transportation. Previous works have suggested incorporation of many conflicting objectives in the analysis, such as travel cost, population exposure, environmental risk or security concerns. Multiplying the number of objectives leads to complex shortest path problems that often have several ef...