Efficiency drive

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Efficiency

drive

With growing numbers of

passengers and trains at

Amsterdam Airport Schiphol

train station, new research is

helping the operator to

improve the boarding and

alighting process of passengers

Words | Jeroen van den Heuvel, Delft University of Technology & Netherlands Railways; and Winnie Daamen, Delft University of Technology

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T

he train station at Amsterdam Airport Schiphol is characterized by a rapid development of rail traffic and numbers of passengers. The station has been in use since December 21, 1978, as part of a new railway line between Schiphol and Amsterdam South. The two train platforms – one central platform with two tracks, and one side platform with one track – were situated in the Schiphol railway tunnel directly under the airport. In 1981, the line was extended to Amsterdam RAI to the east of the city, and Leiden station to the south. In Leiden, the railway line connected to the existing main line between Amsterdam Central and The Hague, via Haarlem. The number of arriving and departing train passengers at Schiphol train station grew to more than 5,000 per average working day; and the number of trains to four trains per hour, per direction.

In 1986, a new rail link between

Amsterdam Central station and Schiphol was opened. Since then, trains have replaced the existing bus network to the city center of Amsterdam. Trains between Amsterdam and Schiphol ran four times per hour, per direction. The total number of trains at Schiphol station increased to eight trains per hour, per direction. Further extension of the rail line from Amsterdam RAI to Almere and Lelystad in the late 1980s added another train per hour, per direction. At the beginning of the 1990s, Schiphol station was used by approximately 30,000 train passengers per average workday.

Due to the rapid development of air traffic, it was predicted that the station and the railway tunnel would be at capacity by the end of the 20th _{century. Therefore, the}

government decided to replace the station building and double the number of tracks and platforms. In 1995, the new station hall was opened. Instead of a separate station building next to the airport terminal building, the station hall – Schiphol Plaza – was integrated into the airport terminal building, providing a seamless, indoor link between trains and airplanes. The four tracks and three central platforms with six platform tracks have been in operation since 2001.

A series of new railway lines connecting Schiphol have been opened in the last 10 years: a direct link between Amsterdam South and Utrecht (2006); a direct link between Schiphol and the northwest of the Netherlands (2006); the high-speed line

more than 20 trains per hour, per direction, consisting of various rolling stock

compositions, train lengths and train door configurations. Approximately 70,000 train passengers use the station on an average workday. Due to the wide variety in destinations of trains stopping at Schiphol, the station has become an important transfer node in the national railway network, as well as in the local public transport network.

Study methods

Today, the train station in Schiphol is again operating at capacity. The Schiphol railway tunnel, including the station, is considered the most important bottleneck in the national railway network. Although

Due to the wide variety

in destinations of trains

stopping at Schiphol, the

station has become an

important transfer node in

the national railway network

several operational measures are currently being studied to keep the station operating safely and smoothly with increasing passenger numbers.

In this context, Netherlands Railways (NS) held a pilot in September 2013 to determine the impact of the train position along the platform on the dwell times of trains at the station. Qualitative observations indicated that a change of the train stopping position at the platforms might improve the boarding process, and decrease station dwell times of trains. For historical reasons, trains currently stop with their first door at the platform section where the most-used escalators to the station hall are situated. This triggers a large number of waiting

(departing) passengers to walk to the first train door as soon as the train arrives, thereby blocking arriving passengers who want to exit the train. A stopping position of about 65-80ft (equivalent to one to two coaches) beyond the most-used escalators was expected to trigger a distribution of departing passengers over multiple train doors and a decrease of the blocking effect

Netherlands are indicated to the train driver by stop signs along the platform track. By a number on the sign, the driver knows where to position the front of his train based on its length (for example ‘8’ refers to an eight coach train). For temporary situations, these signs can be overruled by a blue signal at the platform. This pilot was designed to

intervene in the stopping position of the train using this blue signal. By varying the position of the blue signal at the platform, the stopping position of the trains was adjusted. For each train, the research team determined the position of the blue light at the platform, based on the (expected) train length, type of rolling stock (such as engine with cars or multiple unit), and the pilot scenario to be tested. Two stop-position scenarios were created: the current stopping position as defined by the stop signs along the platform track; and the experimental stopping position 65-80ft downstream.

Biased observations

Station dwell times and composition of individual trains were derived from the train traffic control center (TTCC) logs, which log track occupation times, train length, rolling stock type, and signal colors of the start (entry) and the end (exit) signals of each platform track at Schiphol. The platform track occupation time was used as a proxy for the station dwell time of the train. External influencing factors were identified by analyses of TTCC logs and CCTV footage of the surveillance system. Biased observations were excluded when at least one of the following factors was identified: • A delayed train was identified by comparing entry signal data to the train schedule. Trains with delays over three

Qualitative observations

indicated that a change of the

train stopping position at the

platforms might improve the

boarding process, and decrease

station dwell times of trains

of a real-life operational experiment was chosen, as it was the most suitable research methodology for this case. Firstly, there was a lack of essential data for a computer simulation, for example on the choice of waiting location at the platform of departing passengers, the choice of station exit of arriving passengers, the choice of train doors of both arriving and departing passengers, and the impact of luggage on passenger flows. Secondly, an experiment could be organized relatively easy because all required stakeholders supported the pilot and its operational impacts were minimal. Thirdly, an experiment delivers more intuitive results, which is important for acceptance of the findings.

Just like in many other countries, train stopping positions at station platforms in the

ABOVE Amsterdam Airport Schiphol train station handles around 70,000 passengers every day RIGHT

The study looked at the effect of different stopping positions on passenger boarding and overcrowding

Train stopping signs

Blue light positions Train stopping signs

Escalators and stairs

Current train stopping positions

Experimental train stopping positions

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minutes were excluded from the data set, because large delays cause an accumulation of departing passengers waiting at the platform. As more passengers will board a delayed train, the dwell time will increase. • From the exit signal data, it could be established whether a train’s stop at the station was extended by a red signal due to a conflicting train ahead. A red signal forces a train to wait at the platform, even when passengers are no longer boarding the train. • In some instances, rolling stock defects or service disruptions at sections before Schiphol resulted in other-than-planned train lengths at Schiphol train station; or in trains that consisted of different rolling stock. These changes may have an impact on the passenger boarding process and the station dwell time.

• With CCTV footage, wrongly positioned trains could be identified. Depending on the exact position, they were either grouped in one of the pilot scenarios or excluded from the data set.

• Incidents with impact on the station dwell time were excluded after being identified by combining an outlier analysis on station dwell time data with CCTV footage observations and on-site registrations by the operating staff.

With data from ticket sales, each pilot day was classified as being ‘low’ or ‘high’ in terms of passenger demand. In the data set, trains

arriving and departing on low demand days were grouped accordingly, as were the trains on high demand days.

Analyzing the results

The initial data set consisted of 285 trains that ran on September 10-23, 25 and 26, 2013 (working days), between 8:00am and 11:30am. After excluding biased

observations, 196 trains remained in the data set for analysis. These observations were grouped in four classes, based on stopping position and demand: current + low demand (99 observations); experimental + low demand (20); current + high demand (47); experimental + high demand (30). Statistical tests on the grouped observation revealed the following:

• High demand results in an increase of average station dwell time of approximately 20 seconds (131 versus 114 seconds), and a higher standard deviation (57 versus 45 seconds). This is according to expectations:

more passengers result in longer boarding times and thus longer dwell times of trains. • In low demand situations, the experimental stopping position of trains does not result in shorter station dwell times of trains, as both groups were found to have an average dwell time of 110-120 seconds. This indicates that the experimental stopping position has no effect when the number of boarding passengers is low.

• In peak demand situations, the experimental stopping position of trains results in shorter dwell times of trains compared with the regular stopping position (111 versus 144 seconds). This is according to pre-pilot expectations: a train stopping position of 65-80ft beyond the most-used escalator results in shorter train dwell times due to a better pedestrian process on the platform. Moreover, the experiment resulted in a lower standard deviation of the dwell times (31 versus 66 seconds). Variability of dwell times decreases, which results in more robust train operations at this station and its adjacent railway sections.

Conclusion

The Schiphol train experiment shows that under regular operating conditions, the experimental train stopping position improves the boarding and alighting process of passengers when demand is high. A decrease of the average dwell time of about 30 seconds per train (approximately 25%) at Schiphol has been found, as well as a considerable decrease in the variation in station dwell times. Although not analyzed, it is plausible that a similar effect occurs in case of passenger accumulation on the platform due to delayed train arrivals. No trade-offs have been identified since the experimental train stopping position has no negative effects on train dwell times when demand is low.

The pilot indicates that significant positive effects in the very congested railway section of the Schiphol railway tunnel can be attained by optimizing the pedestrian processes. To minimize station dwell times of trains, a set of operational measures for Schiphol station is being developed, concerning platform layout, real-time train information and train stopping position. The pilot has also provided useful insights for other stations in the Netherlands and abroad, which cope with

Under regular operating

conditions, the experimental

train stopping position

improves boarding and

alighting processes of

passengers

RIGHT The different types of rolling stock used at Amsterdam Airport Schiphol LEFT

The station is a key part of the local public transport network

Rolling stock types, lengths, train door positions

VIRM4 = intercity, double deck multiple unit, four coaches

VIRM4 = intercity, double deck multiple unit, six coaches