Image analysis for morphology, rheology and degradation study of railway ballast: A review

The performance and deformation of ballast bed are significantly influenced by the particle morphology (size and shape), the rheology (translation and rotation), and the degradation (breakage and abrasion). Regarding the ballast particle morphology, the ballast particle size is generally measured by sieving and described with the Particle Size...

Analysis on Adhesively-Bonded Joints of FRP-steel Composite Bridge under Combined Loading: Arcan Test Study and Numerical Modeling

The research presented in this paper is an experimental study and numerical analysis on mechanical behavior of the adhesively-bonded joint between FRP sandwich bridge deck and steel girder. Generally, there are three typical stress states in the adhesively-bonded joint: shear stress, tensile stress, and combination of both. To realize these...

An assessment method of rail corrugation based on wheel–rail vertical force and its application for rail grinding

In practice, the assessment and treatment of rail corrugation are quantitatively based on the corrugation depth. Wheel–rail vertical forces (WRVF), as a direct reflection of wheel–rail interaction, can give expression to the corrugation depth and thus serve as a key parameter for assessing the corrugation. In this paper, we propose an...

Data-driven ballast layer degradation identification and maintenance decision based on track geometry irregularities

Ballast layer defects are the primary cause for rapid track geometry degradation. Detecting these defects in real-time during track inspections is urgently needed to ensure safe train operations. To achieve this, an indicator, the track degradation rate (TDR) was proposed. This rate is calculated using track geometry inspection data to locate...

Moisture absorption/desorption effects on flexural property of Glass-fiber-reinforced polyester laminates: Three-point bending test and coupled hygro-mechanical finite element analysis

Influence of moisture absorption/desorption on the flexural properties of Glass-fibre-reinforced polymer (GFRP) laminates was experimentally investigated under hot/wet aging environments. To characterize mechanical degradation, three-point bending tests were performed following the ASTM test standard (ASTM D790-10A). The flexural properties...

Performance assessment on high strength steel endplate connections after fire

Purpose – This study aims to reveal more information and understanding on performance and failure mechanisms of high strength steel endplate connections after fire. Design/methodology/approach – An experimental and numerical study on seven endplate connections after cooling down from fire temperature of 550°C has...

Effects of Adhesive Connection on Composite Action between FRP Bridge Deck and Steel Girder

The FRP-steel girder composite bridge system is increasingly used in new constructions of bridges as well as rehabilitation of old bridges. However, the understanding of composite action between FRP decks and steel girders is limited and needs to be systematically investigated. In this paper, depending on the experimental investigations of...

Assessment of ballast layer under multiple field conditions in China

Ballast layer condition should be more regularly and accurately inspected to ensure safe train operation; however, traditional inspection methods cannot sufficiently fulfil this task. This paper presents a method of ground penetrating radar (GPR) application to reflect ballast layer fouling levels under diverse field conditions (annual gross...

Ballast fouling inspection and quantification with ground penetrating radar (GPR)

Ground penetrating radar (GPR) has been applied for ballast layer inspection for two decades, mainly for the analysis of ballast layer fouling levels. However, some issues that affect the inspection quality remain unsolved, such as issues involving the GPR equipment quality (antenna) and the correlation between the GPR indicator and fouling...

Coupled hygro-mechanical finite element method on determination of the interlaminar shear modulus of glass fiber-reinforced polymer laminates in bridge decks under hygrothermal aging effects

To investigate the mechanical degradation of the shear properties of glass fiber-reinforced polymer (GFRP) laminates in bridge decks under hygrothermal aging effects, short-beam shear tests were performed following the ASTM test standard (ASTM D790-10A). Based on the coupled hygro-mechanical finite element (FE) analysis method, an inverse...

Effects of crumb rubber size and percentage on degradation reduction of railway ballast

Higher speed, more freight and frequent maintenance increase ballast degradation and reduce the ballast lifespan. To reduce ballast degradation, crumb rubber used as buffering aggregates in ballast bed is relatively unexplored and needs more studies, because using it has the advantage of reusing the waster rubber and absorbing the noises. The...

Behaviour of High Strength Steel Endplate Connections in Fire and after Fire

The aim of this research is to reveal more information and understanding on behaviour and failure mechanisms of high strength steel endplate connections (combining high strength steel endplates with either mild steel or high strength steel beams and columns in endplate connections) in fire and after fire, for an effective application of high...

Activity of High Performance Steel Structures Research Council (HPSSRC)

Editorial

Editorial: Implementation of high-strength, high-performance steel structures

Material behavior of high strength steel S690 in fire and after fire

A New Input-Parallel-Output-Series Three-Phase Hybrid Rectifier for Heavy-Duty Electric Vehicle Chargers

This paper proposes a solution to the circuit topology of heavy-duty electric vehicle (HDEV) chargers. In light of the original hybrid rectifier, a new unidirectional Input-Parallel-Output-Series (IPOS) three-phase hybrid rectifier is proposed and analyzed. The IPOS topology is advantageous at ultra-high power rating to interface the next...