Abstract
This paper studies the effect of temporary speed restrictions (TSR) in railways. We present a method for analyzing the effect of TSR. TSR, or slow orders, are imposed on the railway to ensure safe use of the infrastructure. We have documented that TSRs give variations in the running times for trains. The impact of the TSR is basically depending on several factors, including the difference in speed between normal and reduced speed, the length of the TSR and the length and weight of the train. We found that speed restrictions typically caused delays up to 60 seconds. A best fit analysis indicates that a TSR adds about 25 seconds plus added time depending on the length of the TSR. This corresponds relative well with theoretically expected values. The effect of TSRs is on average relatively well aligned with theoretical calculations. However, the variations are large. Our study has shown that TSRs can have negative effects on the precision of the railway system. As a part of the research, we developed a tool that identifies and evaluates the effect of TSRs on traffic.