Lecture

Railway Infrastructure Design

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In course

CIVIL-463: Design and construction of roadways

Ce cours permet de maîtriser les principes et les bases de la conception des voies de circulation (infrastructures routières et ferroviaires). Il traite les bases des projets, la géométrie, la sécurité routière, les matériaux utilisés, les techniques de co ...

Description

This lecture focuses on the design of railway infrastructure, covering topics such as the components of railway tracks, materials used, analytical dimensioning methods, and the decision-making diagram proposed by the Swiss Federal Railways. The instructor explains the importance of considering various factors like load distribution, wheel diameter, and train speed when dimensioning railway tracks. The lecture also delves into the design of rails, sleepers, and ballast, emphasizing the need for different materials to withstand varying levels of stress. Additionally, the lecture discusses the calculation of stresses on the rail, including vertical, longitudinal, and lateral forces, as well as the impact of dynamic effects. The design process involves evaluating the rail's resistance to bending, shear forces, and deflection, ensuring that the railway components can withstand the applied loads.

Instructor

Micaël Tille

Official source

Related concepts (28)

Stress–strain analysis

Stress–strain analysis (or stress analysis) is an engineering discipline that uses many methods to determine the stresses and strains in materials and structures subjected to forces. In continuum mechanics, stress is a physical quantity that expresses the internal forces that neighboring particles of a continuous material exert on each other, while strain is the measure of the deformation of the material. In simple terms we can define stress as the force of resistance per unit area, offered by a body against deformation.

Deflection (engineering)

In structural engineering, deflection is the degree to which a part of a structural element is displaced under a load (because it deforms). It may refer to an angle or a distance. The deflection distance of a member under a load can be calculated by integrating the function that mathematically describes the slope of the deflected shape of the member under that load. Standard formulas exist for the deflection of common beam configurations and load cases at discrete locations.

Stress (mechanics)

In continuum mechanics, stress is a physical quantity that describes forces present during deformation. An object being pulled apart, such as a stretched elastic band, is subject to tensile stress and may undergo elongation. An object being pushed together, such as a crumpled sponge, is subject to compressive stress and may undergo shortening. The greater the force and the smaller the cross-sectional area of the body on which it acts, the greater the stress. Stress has units of force per area, such as newtons per square meter (N/m2) or pascal (Pa).

Bending

In applied mechanics, bending (also known as flexure) characterizes the behavior of a slender structural element subjected to an external load applied perpendicularly to a longitudinal axis of the element. The structural element is assumed to be such that at least one of its dimensions is a small fraction, typically 1/10 or less, of the other two. When the length is considerably longer than the width and the thickness, the element is called a beam.

Structural analysis

Structural analysis is a branch of solid mechanics which uses simplified models for solids like bars, beams and shells for engineering decision making. Its main objective is to determine the effect of loads on the physical structures and their components. In contrast to theory of elasticity, the models used in structure analysis are often differential equations in one spatial variable. Structures subject to this type of analysis include all that must withstand loads, such as buildings, bridges, aircraft and ships.

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