Unknown White Powder on Wires for Bridge
Mike Lindblom
Seattle Times
__________
Tacoma, Washington (US):
An unknown white powder has been seen on some of the 19,000 miles of wire imported for installation on the new Tacoma Narrows Bridge, forcing builders to perform tests on just what it is.So far, the state Department of Transportation doesn't know whether any wires need to be replaced, said spokeswoman Claudia Cornish, who expects more answers next week.
Oxidation may have occurred in the zinc coating, but it's unclear whether that could weaken the wires, she said.
Workers last week discovered the powder while they were "spinning" the pencil-width wire along the length of the span, through its tall towers and shore-side anchors. Eventually, the wires will be bundled into a pair of thick suspension cables — one to hold up each flank of the massive deck.With the spinning task one-fourth complete, none of the wire that's already fastened has showed signs of oxidation, Cornish said.
Nov 26, 2005
Mike Lindblom
Seattle Times
__________
Tacoma, Washington (US):
An unknown white powder has been seen on some of the 19,000 miles of wire imported for installation on the new Tacoma Narrows Bridge, forcing builders to perform tests on just what it is.So far, the state Department of Transportation doesn't know whether any wires need to be replaced, said spokeswoman Claudia Cornish, who expects more answers next week.
Oxidation may have occurred in the zinc coating, but it's unclear whether that could weaken the wires, she said.
Workers last week discovered the powder while they were "spinning" the pencil-width wire along the length of the span, through its tall towers and shore-side anchors. Eventually, the wires will be bundled into a pair of thick suspension cables — one to hold up each flank of the massive deck.With the spinning task one-fourth complete, none of the wire that's already fastened has showed signs of oxidation, Cornish said.
Nov 26, 2005
