A Calculation Method of Temperature Crack Width in Track Slab

Abstract

The invention discloses a calculation method for width of a temperature crack of a track slab. The calculation method comprises the following steps: (1) determining a basic parameter of a cracked track slab, dividing the track slab into a plurality of parent units according to a crack spacing lcr and dividing each parent unit into n subunits with length of delta x, (2) calculating stress sigma s and strain epsilon s of a longitudinal reinforcement at a cross section of the crack, (3) assuming initial binding slippage s0 of beam end cross sections of the parent units and calculating initial binding stress tau b,0 according to a constitutive relation of binding stress between a reinforcement and concrete and slippage, (4) performing iteration solution on the subunits by an equilibrium equation and a deformation compatibility equation according to the constitutive relation of the binding stress and the slippage and judging whether a solved result meets a boundary condition, and (5) calculating the width w of the temperature crack of the track slab. Compared with the prior art, the method can quantitatively calculate the maximum width of the concrete temperature crack of the track slab, can make up the deficiency of domestic study on the temperature crack of the track slab, provides a support for design of a structural reinforcement of the track slab, is clear and visual in structure, and facilitates program realization.

Description

technical field [0001] The invention relates to the technical field of railway engineering application calculation and design, in particular to a calculation method for the temperature crack width of a track plate. Background technique [0002] With the widespread construction of ballastless tracks in my country in recent years, the cracking of track slabs under temperature loads is a common technical problem in the construction and operation of high-speed railways. The insulation performance of the ballast track weakens the bearing capacity of the track, and may also endanger the safe use of the ballastless track. [0003] Under the temperature load, the concrete shrinkage of the reinforced concrete continuous track slab produces axial pressure, which causes cracks in the track slab. As the temperature load continues to increase, the crack width remains unchanged after reaching the maximum value. At the same time, between the two cracks, due to the concrete reaching its ten...

AI Technical Summary

Problems solved by technology

[0004] At present, most domestic research on the maximum width of temperature cracks in ballastless track track slabs focuses on qualitative explanations, and it is impossible to directly calculate the maximum crack width of track slabs under temperature loads.

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