INTRO: Construction of the initial heavy metro line serving the Puerto Rican capital San Juan is approaching the midway point, with the first cars expected to start test running early next year
BYLINE: Klaus Tiedemann
Project Director, Siemens Transit Team
TOWARDS THE END of this year, a pre-series married-pair of metro cars for the Puerto Rico Tren Urbano will arrive in San Juan. The first two of the 74 vehicles are now being fitted out in Sacramento, whilst a further five bodyshells have been completed by Siemens SGP in Wien. On the ground, tracklaying began with a ’first weld’ ceremony on July 2, and civil engineering for the initial route is on course for completion by the end of 2001.
The need for some form of rail network in the San Juan Metropolitan Area has been identified by study after study for more than 20 years (RG 1.96 p35). More than 90% of all home-to-work trips are made by car, and the density of vehicles per km of road is three times the US average. Population and job density plus rising travel demand indicate the road network is nearing capacity.
The Puerto Rico Department of Highways & Transportation (PRHTA) decided to adopt a turnkey approach which was largely untested for new-start rail projects in North America. In July 1996 the Department awarded a turnkey contract to a Siemens-led consortium known as the Siemens Transit Team, for the country’s first urban railway and its largest ever public works project.
Designated by the US Federal Transit Administration as one of four turnkey demonstration projects, and the only new start in the programme, Tren Urbano is a bold departure for the North American transit industry. While the turnkey approach has been slow to take off in the USA, it can help expedite development, reduce costs, and allocate risks and rewards more rationally between the public and private sectors.
Ironically, despite a continuing strong federal commitment to transit funding, increased demand for finance at the local level is outpacing available resources, forcing operators to consider alternative procurement policies.
DBOM concession
The 17·2 km first phase is a double-track standard-gauge line with 16 stations able to handle six-car trains. Of these, 10 will be elevated; four will be at grade or in an open cut, and two will be underground. There will be a maintenance depot midway along the route, which will also house the operations control centre.
In the initial phase, the line will operate for 20h each day, with a peak hour headway of 4 min. Trains will use full ATO, but will still have an operator. PRHTA is currently looking at ways to integrate the metro with other modes, including, buses, publicos (minibuses), taxis, pedestrians and private cars.
Siemens is supplying vehicles, track, operations control centre, power distribution network, communications and train control systems, as well as building two stations, the OCC, depot and track maintenance yard. Upon completion, Siemens will operate and maintain the whole line. While the Systems & Test Track sub-project is a true turnkey contract, civil engineering work on six other sections of the route has been directly awarded by the Authority to so-called Alignment Section Contractors.
The consortium’s primary partners are Siemens Transportation Partnership, the turnkey arm of Siemens Transportation Systems Inc, local engineering firm Juan R Requena & Associates, and Alternate Concepts Inc of Boston, which will manage the operations and maintenance. Other team members include Parsons Brinckerhoff Transit & Rail Systems Inc for interface design and project oversight and the Redondo-Perini Joint Venture for civil construction and trackwork. Lord Electric and Mass Electric Construction are responsible for communications and electrical installation (Fig 1).
STT is also providing technology transfer, which will help to establish a cadre of transit construction and management professionals in Puerto Rico able to export their services to the Latin American market.
Project milestones
By mid-1999, detailed design of the fixed installations has reached 75%, while construction is approaching 50%. Systems design work is 90% complete and manufacture is under way. The first cars are nearing completion, and several power distribution units have been shipped. The first substation has been installed, and power cabling is in progress. Rails are being delivered and welded into 400m lengths for laying.
The next major milestone will be the delivery of the first married pair for a demonstration run at the end of this year. The test track should be ready for commissioning and testing to start in the first half of 2000. However, minor delays, in part caused by Hurricane George, may see the planned opening in November 2001 slip to the first half of 2002.
The 74 stainless-steel metro cars ordered by PRHTA are equipped with three-phase AC drives and advanced signalling, monitoring, and diagnosis systems. Maximum speed will be 100 km/h. Each car will carry 72 seated and 108 standing passengers (Fig 2). They will run as married pairs, with trains formed of one, two or three pairs according to demand.
A 750 V DC third rail traction supply was selected to minimise visual intrusion and reduce vulnerability to storm and hurricane damage. Electrification equipment is coming from Siemens’ Traction Electrification Division in Portland, Oregon. There will be five 38 kV Bulk Power Supply Substations rated at 25 or 33MVA, which will feed 10 Traction Power Substations and 17 Station Substations at 13·2 kV AC. The 4·4MVA traction power substations will provide the 750 V DC for the main line and depot, whilst the station substations produce 480 V AC to power local services and station equipment. All substations will be controlled remotely from the OCC using Scada.
The transmission-based train control system is coming from Siemens subsidiary Matra Transport International; it is derived from Sacem and the latest Digisafe technology developed for Météor in Paris, but with US signalling components. Cable loop transmission, combined with Sacem fixed blocks sub-divided in stations plus a new speed measurement system offer a high level of performance. Requirements include multiple train configurations, bidirectional operation on each track, a variety of degraded service options, and minimum headways of 90s with a 30s station dwell time.
Speed measurement is based on ’non-permanent free-axle activation’, depending on the train configuration. This will give accurate speed measurement with minimal impact on vehicle performance, simpler operation and maintenance, and still provide the stopping accuracy required with platform screen doors. These are envisaged for the underground stations in the future.
The lineside ATC and interlockings are integrated in the same equipment. Sacem uses a proven single processor principle, with safety based on the coding of data and processing.
The OCC has one security and three line controller consoles, which can also be used for training. The Scada and Automatic Train Supervision use the same graphics display, with an 1500 x 7000mm mapboard that allows the operator to open several windows at a time to manage any operational situation.
Automatic Train Regulation can be provided from any of several archived timetables or with on-line intervention by the operator. The system is alarm driven, with any failure triggering both visual and audible alarms for the operator. Integrated into each console is a Computer-Based Dispatching System, which allows co-ordinated telephone, radio, public announcement and variable sign messages to be issued from one terminal. CCTV enables the security console operator to view all stations.
Learning for the future
From the consortium’s perspective, the most challenging parts of this project were the establishment of a multinational, multicultural co-operative and the separate implementation of a fixed facilities sub-contract, which required effective management of many interfaces. Nevertheless, Tren Urbano is demonstrating the benefits that can be achieved with a hybrid turnkey approach.
With the first line well on the way to completion, attention is now turning to further expansion. In the long-term, PRHTA envisages that the metro will serve all major activity centres in the San Juan Metropolitan Area (map). The first 2 km extension, Phase IA to Minillas, is already in the environmental approvals process. This will be followed by the 12 km Phase II running east from Río Piedras to a park and ride facility in Carolina; Phase III would leave the Phase IA extension near the Minillas Government Centre and run east for 7 km to the international airport in Isla Verde. Phase IV will run 5 km west from Minillas to Old San Juan; and Phase V will branch off the first line to head south to the municipality of Caguas. n
CAPTION: Above right: Tracklaying work began on the test track alongside the depot at the beginning of July
Below: Fig 1. Organisation of the Siemens Transit Team and the responsibility of the member companies
CAPTION: Fig 2. The 23 m long cars will each carry 72 seated and 108 standing passengers; they will operate in married pairs
CAPTION: Left: The Torrimar/ Las Lomas section of the first line is being built by STT as a test section forming part of the Systems & Test Track Turnkey Contract
CAPTION: Below: Martínez Nadal station is under construction alongside the future depot site