Analysis of the Factors Influencing on Bird Nesting and Its Impact on Railway Operation

Abstract

This paper studies the affecting factors on bird nesting on electronic railway catenary lines, and the impact of bird nesting events on railway operation. Firstly, with one year’s bird nest events in form of unstructured natural language collected from Shanghai Railway Bureau, the records were structured with the help of Python software tool. Secondly, the method of root cause analysis (RCA) was used to identify all the possible influencing factors which are inclined to affect the probability of bird nesting. Thirdly, the possible factors then were fallen into two categories to meet subsequent analysis separately; category one was Outside Factors (i.e., geographical conditions-related factors), and the other was Inside Factors (i.e., railway-related factors). As to Outside Factors, such as temperature, vegetation coverage, population, longitude and latitude, nearby water, etc. by using some geographical APIs offered by Amap and the tools of ArcGIS, geographical data were processed in relation to nest events on the visual map and their correlationship was studied. It was observed that factors of city population, geographic position affect nesting observably. As to railway-related Inside Factors, statistic analysis method was used to disclose the significant influencing factors to bird nesting. Statistical result indicated that factors of season, rail location (station or section) and the specific equipment part of railway catenary lines had significant effects on nest events. Finally, it was demonstrated that both location and nesting on equipment part have no correlation with delay, while railway type had a significant but low correlation with delay. Two lognormal stochastic models were put forward which are the best-fit models for delay caused by bird nesting events of both normal-speed and high-speed railway, which discloses the principle of impacts of nest events on railway operation.