Higher-speed rail

But an upgrade to existing track currently in use, with busy traffic in some segments, introduces challenges associated with the construction work that could potentially disrupt the train services.

The project employed the Solid State Interlocking with the newly laid fiber-optic communication between the components to use three computer systems to control the signals.

The track upgrade in the project included changing to use concrete ties and to use new standard of rail weight at 60 kg/m (121 lb/yd) in order to support the new top speeds of 160 km/h (100 mph).

Even with newer turnouts (rated #20), the diverging speed limit is still at 45 mph (70 km/h) which would significantly slow down the higher-speed train passing through those sections.

In the United States, a TRT is used by Union Pacific Railroad on the track shared with future higher-speed rail service in Illinois area.

The fixed-tension catenary which is acceptable for low speeds may not be suitable for regular higher-speed rail services, where a constant tension is automatically maintained when temperature changes cause the length of the wire to expand or contract.

This was a major consideration in the electrification of the German Democratic Republic network, as lignite (and therefore electricity) was cheap and plentiful domestically whereas oil had to be imported at world market prices.

However the operating speeds of this type of systems cannot be greater than 100 mph (160 km/h) due to its limitation of the power supply gaps at turnouts and grade crossings.

[70] Additionally, Queensland Rail's Tilt Train, the Prospector and NSW TrainLink's XPT all have a top service speed of 160 km/h (99–100 mph).

[81] On 1 March 2019, second Tejas Express of the country was flagged off between Chennai Egmore and Madurai Junction by Prime Minister Narendra Modi.

[89] It was designed and built by Integral Coach Factory (ICF) at Perambur, Chennai under the Indian government's Make in India initiative over a span of 18 months.

[96] The Delhi Meerut Regional Rapid Transit System (RRTS), also known as RapidX, is a semi high-speed rail project inaugurated in 2023.

[100] The 8-hour journey from New Delhi to Varanasi station has the Chair Car CC Class fare of ₹1,755.00 and covers the total distance of about 762 kilometers.

[117][118] Amtrak Cascades, a 467-mile (752 km) intercity rail service, stretches from Eugene, Oregon, through the State of Washington to Vancouver, British Columbia, in Canada.

The Northern Lights Express project, in the planning stages and proposed to begin construction in 2017, would upgrade the BNSF trackage between Minneapolis and Duluth to support service up to 90 mph (145 km/h).

In 1998, New York State initiated a $185 million program in partnership with Amtrak to increase the speeds of the Empire Service to 125 mph (200 km/h) by reconstructing all seven gas-turbine Turboliner trainsets, originally built in 1976–1977, to the new RTL-III specification.

The proposal was to increase the top speeds to 110 mph (175 km/h) in the network connecting Cleveland, Columbus, and Cincinnati, commonly referred as the 3-C corridor.

With 320.79 km length, Dhaka-Chattogram is the main business corridor and life line of BR, and at present, the railway route is a circuitous way through Tongi-Bhairab Bazar-Brahmanbaria-Cumilla-Chattogram.

Under the 18-month contract, the Consortium's responsibilities will include identifying alternative alignments, assessing the viability of the project, preparing detailed engineering design, and cost estimation.

[25][137][138] Another feasibility study is ongoing as part of the Northern New England Intercity Rail Initiative to connect between Boston and Montreal trains at top speeds of 90 mph (145 km/h).

[7] On 3 July 2014, a trial run with new top speeds of 160 km/h (100 mph) was successfully completed on a journey of 200 km (125 mi) between Delhi and Agra.

[143] The KTM ETS is an inter-city rail service operated by Keretapi Tanah Melayu Berhad utilizing electric multiple units.

Advocacy group Greater Auckland proposed the Regional Rapid Rail initiative in 2017, including tilt trains with a maximum speed of 160 km/h.

In December 2018, the Government of New Zealand committed funding to reintroducing a five-year trial rail service between Papakura in southern Auckland to Hamilton, starting in 2020.

[146] The state-owned Philippine National Railways plans to rebuild its historic South Main Line from Manila to the Bicol Region in the southeastern tip of Luzon.

In January 2022, PNR general manager Junn Magno defined the agency's future high-speed rail projects to be electrified railways with a maximum speed of at least 200 km/h (120 mph).

An alternative is to have intermediate stops in Ohio cities including Ashtabula, Warren, and Youngstown before heading back to New Castle, Pennsylvania.

This is in response to another advocacy group in Indiana that gained funding for the Columbus, Ohio – Fort Wayne – Chicago route that is already in feasibility study stage.

As a possible route that goes through the states of Kentucky and Indiana, the county expects that Ohio-Kentucky-Indiana Regional Council of Governments will help fund a feasibility study.

[174] In 2018, Vietnam planned to build a higher-speed rail line in the northern part of the country to link between Haiphong, Hanoi, and Lào Cai which is then connected to China.