Sponsored Links
-->

Senin, 05 Maret 2018

Bay Area Rapid Transit - Wikipedia
src: upload.wikimedia.org

The rolling stock of the Bay Area Rapid Transit (BART) system's heavy rail component consists of 662 self-propelled electric multiple units, built from three separate orders. To run a typical peak morning commute, BART requires 579 cars. Of those, 535 are scheduled to be in active service; the others are used to build up four spare trains (essential for maintaining on-time service). At any one time, the remaining 90 cars are in for repair, maintenance, or some type of planned modification work. All trains on the separate automated guideway transit line are in regular use without spares. Bombardier Transportation is manufacturing a complete replacement of the fleet, due to be delivered in batches by Fall 2021. The first ten cars of this replacement fleet entered service in 2018, with all entering service by 2022. With the withdrawal and retirement of the older fleet, there will be 775 vehicles in total, with long term goals of eventually increasing this to 1,081 cars. Diesel multiple units will be utilized on a forthcoming spur line.

The mainline track gauge is 5 ft 6 in (1,676 mm) Indian gauge, significantly wider than the near-universal 4 ft 8 1/2 in (1,435 mm) standard gauge used on freight railroads and most rapid transit systems. It also uses flat-edge rail, rather than typical rail that angles slightly inward. These factors have complicated maintenance of the system, as it requires custom wheelsets, brake systems, and track maintenance vehicles. Trains have a platform height estimated to be 42 inches (1,067 mm). A full consist, which will fill the system's platforms, is limited to ten units, equaling 710 feet (216 m) (assuming A cars on the ends). The automated guideway transit line utilizes off-the-shelf cable car technology developed by DCC Doppelmayr Cable Car: the Cable Liner.


Video Bay Area Rapid Transit rolling stock



Original fleet

A and B series

The A and B cars were built from 1968 to 1971 by Rohr Industries, an aerospace manufacturing company that had recently started mass-transit equipment manufacturing. The A cars were designed as leading or trailing cars only, with an aerodynamic fiberglass operator's cab housing train control equipment and BART's two-way communication system, and extending 5 feet (1.52 m) longer than the B- and C-cars. A and B cars can seat 60 passengers comfortably, and under crush load, carry over 200 passengers. B cars have no operator's cab and are used in the middle of trains to carry passengers only. Currently, BART operates 59 A cars and 389 B cars. The BART A cars have a larger cab window than the C cars, allowing riders to look out of the front or the back of the train.

C series

The C cars feature a fiberglass operator's cab and control and communications equipment like the A cars, but do not have the aerodynamic nose, allowing them to be used as middle cars as well. This allows faster train-size changes without having to move the train to a switching yard. C cars can seat 56 passengers and under crush load accommodate over 200 passengers. The first C cars, referred to as C1 cars, were built by Alstom between 1987 and 1989. The second order of C cars, built by Morrison-Knudsen (now Washington Group International), are known as C2 cars. The C2 cars were identical to the C1 cars but featured an interior with a blue/gray motif. At the time of their construction, the C2 cars also featured flip-up seats which could be folded to accommodate wheelchair users; these seats were later removed during refurbishment. Currently, BART operates 150 C1 cars and 80 C2 cars. The "C" cars have a bright white segment as the final approximately two feet (61 cm) of the car at their cab end.

Refurbishments

Prior to the introduction of the C2 cars, the seats and carpeted flooring in all the cars were brown. In 1995, BART contracted with ADtranz (acquired by Bombardier Transportation in 2001) to refurbish and overhaul the 439 original Rohr A- and B-cars, updating the old brown fabric seats to less-toxic and easier-to-clean, light-blue polyurethane seats and bringing the older cars to the same level of interior amenities as the C2 fleet. The project was completed in 2002. The A, B, and C cars were all given 3-digit numbers originally, but when refurbished 1000 was added to the number of each individual A/B car (e.g. car 633 would become 1633). The C2 cars are numbered in the 2500 series; the C/C1 cars still have 3-digit numbers.

Because one of the original design goals was for all BART riders to be seated, the older cars had fewer provisions such as grab bars for standing passengers. In the late 2000s BART began modifying some of the C2 cars to test features such as hand-straps and additional areas for luggage, wheelchairs and bicycles. These new features were later added to the A, B, and C1 cars.

Prior to 2012, all BART cars featured upholstered seats. It was reported in 2011 that several strains of molds and bacteria were found on fabric seats on BART trains, even after wiping with antiseptic. These included bacteria from fecal contamination. In April, BART announced it would spend $2 million in the next year to replace the dirty seats. The new seats would feature vinyl-covered upholstery which would be easier to clean. The transition to the new seats was completed in December 2014.

Originally all the cars had carpeted flooring. Due to similar concerns regarding cleanliness, the carpeting in all of the cars has been removed. The A and B, and C2 cars now feature vinyl flooring in either grey or blue coloring, while the C1 cars feature a spray-on composite flooring.

Traction motors

Prior to rebuilding, the Direct Current (DC) traction motors used on the 439 Rohr BART cars were model 1463 with chopper controls from Westinghouse, who also built the automatic train control system for BART. The Rohr cars were rebuilt with ADtranz model 1507C 3-phase alternating current (AC) traction motors with insulated-gate bipolar transistor (IGBT) inverters. The Westinghouse motors are still in use on the Alstom C (C1) and Morrison-Knudsen C2 cars and the motors that were removed from the Rohr cars were retained as spare motors for use on them. Cars have a starting accelerating of 3.0 mph/s or 4.8 km/(h?s) and are capable of holding that acceleration up to 31 mph (50 km/h). Residual acceleration at 80 mph (130 km/h) is 0.78 mph/s or 1.26 km/(h?s). Braking rates range from 0.45 mph/s or 0.72 km/(h?s) up to 3.0 mph/s or 4.8 km/(h?s) (full service rate).

The HVAC system on the Rohr BART cars before rehabilitation were built by Thermo King, when it was a subsidiary of Westinghouse; it is now a subsidiary of Ingersoll Rand. The current HVAC systems on the rebuilt Rohr-built Gen 1 cars were built by Westcode and possibly also ADtranz who had subcontracted the HVAC system to Westcode.

Noise

Many BART passengers have noted that the system is noisy, with a 2010 survey by the San Francisco Chronicle measuring up to 100 decibels (comparable to the noise level of a jackhammer) in the Transbay Tube between San Francisco and Oakland, and still more than 90 decibels in 23 other locations. According to BART, the noise in the tunnel used to be "compared to banshees, screech owls, or Doctor Who's TARDIS run amok".

However, then-chief BART spokesperson Linton Johnson stated that BART averages 70-80 dB, below the danger zone, and according to a 1997 study by the National Academy of Sciences, BART ranks as among the quietest transit systems in the nation. Critics have countered that this study analyzed straight, above-ground portions of different systems throughout the country at 30 mph (48 km/h), which is not representative of actual operating conditions. Much of BART is under ground and curvy, even in the Transbay Tube, and has much higher peak operating speeds than many other systems in the country.

Train noise on curves is caused by the wheels slipping along the rails. This slippage also causes noise and surface damage called corrugation. The process by which the noise and corrugation occur is:

  1. Pairs of wheels are attached to one another with an axle such that they must have the same rotational speed, but on a curve the distances the outer and inner wheels travel are different. As a result, the wheels must slip along the rails.
  2. This slippage causes the wheel and track to wear and become uneven (corrugated).
  3. This corrugation causes more noise and corrugation, not only in the original location but elsewhere in the system.

In 2015, after replacing 6,500 feet (1,981 m) and grinding down (smoothing) 3 miles (4.8 km) of rail in the tube, BART reported a reduction of noise there and positive feedback from riders. BART also announced that the new train cars expected to enter service in December 2016 (see below) will be quieter, thanks to "'micro-plug' doors [that] help seal out noise".


Maps Bay Area Rapid Transit rolling stock



Fleet of the Future (D and E series)

In a 2010 APTA study, the average age of BART's mainline fleet was reported to be 30 years, longer than the usual lifespan of 25 years. Despite the purchase of newer cars over the years, the majority of the active fleet in 2016 was over 40 years old and had traveled over a million miles. Because of this, they have been increasing prone to frequent breakdowns and repairs, decreasing the number of available cars and in turn increasing congestion, especially with the need to increase the fleet size for extensions to the network. Consequently, in 2009, BART began the process of expanding and replacing its railcar fleet. By 2010, it had received proposals from five suppliers, and on May 10, 2012, it awarded a $896.3 million contract to Canadian railcar manufacturer Bombardier Transportation with an order for 410 new cars, split into a base order of 260 cars and a first option order of 150 additional cars. The car was designed by Morelli Designers, an industrial design firm based in Montréal, Canada. On November 21, 2013, BART purchased 365 more cars, for a total fleet size of 775 new railcars, while also accelerating the delivery schedule by 21 months (from 10 cars per month up to 16 cars per month) and lowering procurement costs by approximately $135 million. According to the contract, at least 2/3 of the contract's amount must be spent on U.S.-built parts.

There are two different types of car configurations for the new fleet; a cab car (D cars), which will make up 40% of the fleet, or, 310 cars, and a non-cab car (E cars), which will make up the remainder of the fleet, or, 465 cars. All cars are to be equipped with bike racks, new vinyl seats (54 per car), and a brand new passenger information system which will display next stop information.

A major difference from the older cars is the presence of an extra set of doorways on each side of the new cars to speed up boarding and alighting. They also include redesigned seating, bike racks, digital displays that display travel information, and automatic announcements. Due to potential access issues for people with disabilities, the pilot car layout was modified by the BART board in February 2015 to include two wheelchair spaces in the center of the car, as well as alternative layouts for bike and flexible open spaces.

The first test car was unveiled in April 2016; upon approval, the first 10 cars were expected to be in service in December 2016, and at least 20 by December 2017. This was delayed several times until the production cars were expected to be delivered in October 2017. Delivery of all 775 cars was initially expected to be completed by Fall 2022, with all cars in service by 2023. Bombardier initially agreed to speed production to have all cars available by the end of 2021 and in service by 2022.

In early November 2017, a test train failed a CPUC regulatory inspection due to door issues, leaving the planned late November revenue service in doubt. The first ten-car train received CPUC certification on January 17, 2018, and began revenue service two days later on January 19.


San Francisco's BART Railfan Guide
src: www.railfanguides.us


AGT fleet

The Coliseum-Oakland International Airport line uses a completely separate and independently operated fleet as it uses off-the-shelf cable car-based automated guideway transit technology. The fleet consists of four Cable Liner trains built by DCC Doppelmayr Cable Car arranged as three-car sets, totaling twelve cars. The system is designed to be expanded to four-car trains with a capacity of 148 passengers in the future if necessary.


Gojurn - Getting Around the Bay Area
src: i.imgur.com


eBART fleet

eBART is a spur line built to different design standards than the majority of the mainline; it is non-electrified 4 ft 8 1/2 in (1,435 mm) standard gauge and intended for service by light rail. The vehicle procurement for the line includes eight Stadler GTW trains, with two options to purchase six more. Stadler was the sole bidder on the contract. The first was delivered in June 2016. The trains are diesel multiple units (DMU's) with 2/6 articulated power units, and are based on models previously used in Austin, Dallas and New Jersey.


BART Proposes $3 Million Crackdown On Fare Evaders « CBS San Francisco
src: cbssanfran.files.wordpress.com


Track geometry cars


SF Bay Area Rapid Transit: Orange & Yellow Line BART Trains at ...
src: i.ytimg.com


References

Source of article : Wikipedia