Programm: RETOS COLABORACIÓN 2017
The high-speed market in desert climates has specific characteristics. The influence of the sand in the maintenance of the infrastructure and the railway operation is a subject of special attention for a double reason. On one side, the presence of sand in the contact area between the rail and the wheel can significantly influence the wear of the rail and the wheel, and the corrosion of the rail. And, on the other side, it will change the conditions of adherence of the vehicle to the road. Likewise, the great variations in temperature during the day and the very low humidity suppose exceptional conditions for the rail and ballast. The lack of specific technology for the key elements of the infrastructure (rail and ballast) can mean that the costs of maintenance of the operation are triggered by wear, corrosion, cracks in welds and early degradation of the ballast.
Objectives of the project:
In this context, RAILSAND aims to develop the key technological elements indicated below:
The first objective is the design of the chemical composition of the steel and the development of thermomechanical and thermal treatments and to achieve a new type of rail capable of increasing the resistance to abrasion of desert sand and preventing corrosion.
The second objective is to define an optimal process for the chemical reduction of cast iron slag for the removal of CaO to the level that allows its use in desert climate infrastructures.
The third objective is the development of a SW application that allows calculating the cost of the lane life cycle taking into account the characteristics of the infrastructure, the characteristics of the service (vehicle, speeds, accelerations, adherence) and the characteristics of maintenance (for example rail grinding costs, rail replacement costs, inspection costs). Using this tool, the best type of lane for an infrastructure and operating conditions can be determined, as well as the optimal maintenance strategy.
This tool will be based on the EN60300-3-3  standard, which generically includes the calculation of the life cycle cost, and the adaptation of the concepts to the railway environment is foreseen. The tool will allow sensitivity analysis to be carried out and will offer reference values for the parameters to be used in an agile way even when not all the information on the infrastructure is available.
Additionally, there are the following secondary objectives, the fulfillment of which is necessary to achieve the aforementioned:
Design of tribological models that allow predicting lane degradation due to wheel-rail contact in the presence of sand depending on vehicle dynamics, track layout and grain size. These models are the basis for calculating the life cycle cost of the rail.
Identification of variations in the friction conditions of the wheel-rail contact in the presence of sand. This will allow analysis of safe operating conditions (eg minimum braking distance) for high speed vehicles in situations of reduced grip.
Identification of the sand deposition model as the train passes by the suction generated by it. This model will allow to know the sand conditions on the road, starting point to obtain the prediction models of degradation and the variations in the friction conditions.
Modeling the degradation of the ballast from foundry slag to the passage of railway vehicles.
Ceit will lead the development of infrastructure degradation models (where the participation of ARCELORMITTAL AND COPASA will be necessary) and operating risk models. It will also develop an application for calculating the life cycle cost of Arcelor Mittal lanes, for the evaluation of new designs and materials and their impact on the life cycle.
Likewise, it will actively participate in the tests on the specimens developed by ARCELORMITTAL in collaboration with ITM