Questões de Concurso
Comentadas para analista - economia
Foram encontradas 712 questões
Resolva questões gratuitamente!
Junte-se a mais de 4 milhões de concurseiros!
News release issued at 3:27 pm, October 6, 2013.
The investigation into the cause of a fatal overnight construction accident on the Red Line in Washington, D.C. is ....B.... . The investigation team, led by Metro's Chief Safety Officer, has authorized the release of the following facts and preliminary findings:
The incident occurred shortly after midnight, Sunday, October 6, 2013, in a work zone on the outbound (Glenmont direction) track between Union Station and Judiciary Square.
Contractors and WMATA employees were performing rail renewal, a process that involves removing old sections of rail, installing new sections of rail and related activity such as welding and grinding.
At approximately 12:03 a.m., there was a fire and loud noise that originated near heavy track equipment used to weld rail sections together into a continuous strip.
The fire and loud noise originated approximately 70 to 80 feet from the injured workers. The root cause of the fire/noise has not yet been determined. It is not yet known if there was a fluid leak or another mechanical issue.
The fire was extinguished by workers using a handheld fire extinguisher.
The incident caused a 40-foot section of rail to move, striking three workers (two WMATA employees and a contractor). It is not yet known what caused the piece of rail to move.
The two WMATA employees - one track worker and one supervisor - suffered serious but non-life-threatening injuries from being struck by the piece of rail. They were transported to local hospitals.
The contractor, an employee of Holland Co., was fatally injured as a result of being struck by the piece of rail.
September 4, 2013
By Greg Aragon
Tunneling 100 ft below a busy city with varying substructure is a delicate job, especially when the work comes .....A.... 8 ft of existing tunnels. Such is the case on San Francisco's new $1.5-billion Central Subway Project, which began major subterranean excavation last month.
"The tunnels pass through both soft ground and Franciscan formation, which is heterogeneous rock that is not predictable except in its unpredictability," says Sarah Wilson, a San Francisco Municipal Transportation Agency (SFMTA) resident engineer.
While underground conditions will be tricky, the project's twin earth-pressure-balance tunnel-boring machines will be able to adjust their blades and cut through any sand, dirt or rock, says Wilson. The TBMs, dubbed Mom Chung and Big Alma, are each 350 ft long and weigh 750 tons.
Mom Chung was first out of the 450-ft-long launch box. Over the next 10 months, she will travel north, creating a 1.7-mile-long tunnel. Big Alma will begin digging a southbound parallel tunnel later this month.
The tunnels are the main component of the Central Subway Project, which is extending the Muni Metro T Third Line through one of the most densely populated neighborhoods in the U.S. with three new underground stations and one at street level. Work on the line is scheduled to wrap up in 2019.
To prevent and control ground and adjacent structure settlement, the team will use compensation grouting, in which a horizontal array of grout pipes is installed into a shaft drilled down next to the tunnel alignment. "We are basically preconditioning the ground and making it homogeneous so that there are no surprises for the crossing," says John Funghi, SFMTA program director.
September 4, 2013
By Greg Aragon
Tunneling 100 ft below a busy city with varying substructure is a delicate job, especially when the work comes .....A.... 8 ft of existing tunnels. Such is the case on San Francisco's new $1.5-billion Central Subway Project, which began major subterranean excavation last month.
"The tunnels pass through both soft ground and Franciscan formation, which is heterogeneous rock that is not predictable except in its unpredictability," says Sarah Wilson, a San Francisco Municipal Transportation Agency (SFMTA) resident engineer.
While underground conditions will be tricky, the project's twin earth-pressure-balance tunnel-boring machines will be able to adjust their blades and cut through any sand, dirt or rock, says Wilson. The TBMs, dubbed Mom Chung and Big Alma, are each 350 ft long and weigh 750 tons.
Mom Chung was first out of the 450-ft-long launch box. Over the next 10 months, she will travel north, creating a 1.7-mile-long tunnel. Big Alma will begin digging a southbound parallel tunnel later this month.
The tunnels are the main component of the Central Subway Project, which is extending the Muni Metro T Third Line through one of the most densely populated neighborhoods in the U.S. with three new underground stations and one at street level. Work on the line is scheduled to wrap up in 2019.
To prevent and control ground and adjacent structure settlement, the team will use compensation grouting, in which a horizontal array of grout pipes is installed into a shaft drilled down next to the tunnel alignment. "We are basically preconditioning the ground and making it homogeneous so that there are no surprises for the crossing," says John Funghi, SFMTA program director.
September 4, 2013
By Greg Aragon
Tunneling 100 ft below a busy city with varying substructure is a delicate job, especially when the work comes .....A.... 8 ft of existing tunnels. Such is the case on San Francisco's new $1.5-billion Central Subway Project, which began major subterranean excavation last month.
"The tunnels pass through both soft ground and Franciscan formation, which is heterogeneous rock that is not predictable except in its unpredictability," says Sarah Wilson, a San Francisco Municipal Transportation Agency (SFMTA) resident engineer.
While underground conditions will be tricky, the project's twin earth-pressure-balance tunnel-boring machines will be able to adjust their blades and cut through any sand, dirt or rock, says Wilson. The TBMs, dubbed Mom Chung and Big Alma, are each 350 ft long and weigh 750 tons.
Mom Chung was first out of the 450-ft-long launch box. Over the next 10 months, she will travel north, creating a 1.7-mile-long tunnel. Big Alma will begin digging a southbound parallel tunnel later this month.
The tunnels are the main component of the Central Subway Project, which is extending the Muni Metro T Third Line through one of the most densely populated neighborhoods in the U.S. with three new underground stations and one at street level. Work on the line is scheduled to wrap up in 2019.
To prevent and control ground and adjacent structure settlement, the team will use compensation grouting, in which a horizontal array of grout pipes is installed into a shaft drilled down next to the tunnel alignment. "We are basically preconditioning the ground and making it homogeneous so that there are no surprises for the crossing," says John Funghi, SFMTA program director.