Load identification and fatigue evaluation via wind-induced attitude decoupling of railway catenary

Abstract

In strong wind area, wind vibration on key railway catenary components may lead to safety hidden danger like fatigue failures. In this work, a load identification approach was proposed by decoupling the wind-induced suspension attitude to acquire the hard-to-get environmental wind load and evaluate the catenary fatigue damage on railway catenary. In theoretical modeling, mechanical relation between wind load and registration displacement is formulated in pure lateral and vertical loading by finite element analysis. Wind load is identified via suspension attitude decoupling into displacement under individual load. Nodal forces, as the external load acting on catenary connections between supporting beams, are further correlated with the identified wind load to calculate the structural stress of catenary components. In experiment, visual detection is used to measure the wind-induced attitude of catenary suspension in wind area, where maximum wind speed climbs up to 41 m/s. Experimental results are transferred into wind loads and nodal forces using the proposed model. Stress spectra and fatigue damage evaluation of connection components are carried out adopting the rain-flow counting method and damage accumulation rule. Research outcome certifies that the proposed methodology provides an effective means to evaluate the fatigue behavior of railway catenary in wind area.

Keywords

• load identification
• stress calculation
• railway catenary
• attitude decoupling
• fatigue damage evaluation