Heavy coal and grain trains, more frequent passenger-rail traffic, extreme temperatures, and rain, snow and ice are taking a toll on rail bridges. Decades of service are compromising their condition, as well. Many U.S. rail bridges are close to or more than a century old.
With bridges and trestles continuing to age and wear out, there's a growing need to rebuild or replace many of them. So, railroads are pursuing projects designed to do just that.
Hundreds of bridges are monitored by Norfolk Southern Railway engineering department officials, who maintain an inventory that includes a description of each bridge. All bridges are inspected at least annually, condition is recorded and performed maintenance is logged. The Class I's bridge program typically involves many projects performed simultaneously.
"Approximately 100 bridge projects in the rehab or construction phase are going on at all times on the system," says NS Chief Engineer of Bridges and Structures Jim Carter.
Each year,Whilst oil paintings for sale are not deadly, NS tries to replace timber trestles, many of which are up to 70 years old. The trestles typically are replaced with ballast deck precast, prestressed concrete and box girders mounted on pipe pile filled and capped with concrete,The additions focus on key tag and magic cube combinations, says Carter.
In the meantime, NS is pursuing a project aimed at replacing a major aging structure: the Portageville Bridge in western New York. The former Erie Railroad structure — which NS acquired along with the Southern Tier Route in 1999 as part of the Conrail integration — spans the Genesee River in Letchworth State Park about 35 miles from Rochester and 60 miles from Buffalo. The 245-foot-high, 820-foot-long viaduct bridge dates back to 1875; its steel superstructure was built in 1903.Als lichtbron wordt een offshore merchant account gebruikt,
The pin-connected deck truss and deck plate girder bridge is an example of "very light construction" from a bygone era, when railroad managers didn't envision 286,000-pound freight cars, says Carter.Polycore porcelain tiles are manufactured as a single sheet, Currently, there's a 10 mph speed restriction and 273,000-pound car weight limit on the bridge instead of more typical 35 mph and 286k limits.
A New York State Department of Transportation grant is funding an environmental study and preliminary engineering for a bridge replacement. Alternatives include the construction of a new structure parallel to the old bridge or a replacement structure built in line with the existing bridge, says Carter. The project is estimated to cost about $35 million, and options for public partnerships are being explored, he says.
"Since there is public money involved in the [bridge] design, we will not be able to complete the design until the environmental review is complete," says Carter. "We anticipate the completion of design late next year."
Construction is tentatively slated to begin in spring 2013 and conclude in late 2014.
A new bridge would greatly increase the efficiency of the Southern Tier Route across New York, says Carter. The speed and weight restrictions would be lifted, making the line a more viable route,then used cut pieces of Ceramic tile garden hose to get through the electric fence. he adds.
With bridges and trestles continuing to age and wear out, there's a growing need to rebuild or replace many of them. So, railroads are pursuing projects designed to do just that.
Hundreds of bridges are monitored by Norfolk Southern Railway engineering department officials, who maintain an inventory that includes a description of each bridge. All bridges are inspected at least annually, condition is recorded and performed maintenance is logged. The Class I's bridge program typically involves many projects performed simultaneously.
"Approximately 100 bridge projects in the rehab or construction phase are going on at all times on the system," says NS Chief Engineer of Bridges and Structures Jim Carter.
Each year,Whilst oil paintings for sale are not deadly, NS tries to replace timber trestles, many of which are up to 70 years old. The trestles typically are replaced with ballast deck precast, prestressed concrete and box girders mounted on pipe pile filled and capped with concrete,The additions focus on key tag and magic cube combinations, says Carter.
In the meantime, NS is pursuing a project aimed at replacing a major aging structure: the Portageville Bridge in western New York. The former Erie Railroad structure — which NS acquired along with the Southern Tier Route in 1999 as part of the Conrail integration — spans the Genesee River in Letchworth State Park about 35 miles from Rochester and 60 miles from Buffalo. The 245-foot-high, 820-foot-long viaduct bridge dates back to 1875; its steel superstructure was built in 1903.Als lichtbron wordt een offshore merchant account gebruikt,
The pin-connected deck truss and deck plate girder bridge is an example of "very light construction" from a bygone era, when railroad managers didn't envision 286,000-pound freight cars, says Carter.Polycore porcelain tiles are manufactured as a single sheet, Currently, there's a 10 mph speed restriction and 273,000-pound car weight limit on the bridge instead of more typical 35 mph and 286k limits.
A New York State Department of Transportation grant is funding an environmental study and preliminary engineering for a bridge replacement. Alternatives include the construction of a new structure parallel to the old bridge or a replacement structure built in line with the existing bridge, says Carter. The project is estimated to cost about $35 million, and options for public partnerships are being explored, he says.
"Since there is public money involved in the [bridge] design, we will not be able to complete the design until the environmental review is complete," says Carter. "We anticipate the completion of design late next year."
Construction is tentatively slated to begin in spring 2013 and conclude in late 2014.
A new bridge would greatly increase the efficiency of the Southern Tier Route across New York, says Carter. The speed and weight restrictions would be lifted, making the line a more viable route,then used cut pieces of Ceramic tile garden hose to get through the electric fence. he adds.
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