Railway construction projects along the central railway l

The Centralna Magistrala Kolejowa CMK, Poland’s central railway artery, is a consistently double-track 222km-long railway line connecting the greater Warsaw area with southern Poland. The first section was opened in September 1974. At present, passenger trains travelling along the high-speed line reach speeds of up to 200km/h, while the speed limit for goods trains is 120km/h throughout almost the entire the line. Even higher speed limits are to be achieved by 2020, along with significant reductions in travel times, as part of the project “Modernisation of railway line no 4 – the central rail artery”.

The works during the track closure period began with dismantling the point mechanisms, the facilities for safety and control technology, the overhead lines, the old supporting structures and the pile foundations. After the overhead lines had been dismantled, work began on removing the existing switches and tracks with a KRC 1200 railway crane. A replacement crane was available on standby in case of breakdowns. The old track ballast was removed, the sub-ballast was profiled and compacted, and technical and geo-technical surveys were carried out while the sleepers were still being dismantled. Dismantling the tracks took a total of seven hours, and another 16 hours were needed to clear and remove the old ballast. Once the track had been dismantled, the old sleepers were transported to the adjacent station in low-floor vehicles. Freight carriages carrying the new switch systems were then driven onto the line. After the carriages had been manoeuvred from the transport position to the unloading position, work began on installing the missing track sections. The base course was laid, compacted and levelled while the old ballast was still being removed and the profiling works on the sub-ballast were being carried out. Installing the base course took a total of 19 hours and 13 hours were needed to complete the ballast plane. Once the ballast plane had been created, work began on installing the track frame and the switch systems. This was completed in 25 hours.

Due to the short track closure period, two tamping machines and two ballast regulators were used to tamp the ballast. A total of 45 hopper wagons were used for filling the tracks with ballast. The filling and tamping processes took a total of 23 hours. Over the next ten hours, the installation works for the new overhead lines, including regulation, the welding works, installing the technical control and safety facilities and the hydraulic drive connections, and the operational inspections were all carried out. Thanks to the preparatory works, the work technology employed and the exact planning of every step of the workflow, the stipulated service time plan was met, and the railway line was handed over to the employer in October 2016.