Hector Amezcua / hamezcua@sacbee.com

Caltrans technicians perform a hardness test on a steel rod that was installed in a section of the Bay Bridge in 2010 and then removed recently for inspection.

Senate panel questions Caltrans about Bay Bridge broken bolts, broken trust

Published: Wednesday, May. 15, 2013 - 12:00 am | Page 1A
Last Modified: Saturday, Apr. 12, 2014 - 7:26 pm

Frustrated state senators pressed California Department of Transportation officials at a Tuesday hearing about how they will deal with thousands of suspect steel parts in the new San Francisco-Oakland Bay Bridge which were installed even though they had not met specifications.

"I understand that this is a big project … but we seem to have problem after problem after problem," said Sen. Anthony Cannella, R-Ceres. "What is Caltrans going to do to earn the trust of the public?"

"That is one of my enormous challenges," Caltrans Director Malcolm Dougherty said.

Senators said the slow pace of answers from the agency and its difficulty explaining complex issues in common language had eroded public confidence in Caltrans' stewardship of the Bay Bridge project.

Cannella, an engineer, asked, "When is a project too big for us to do as a state agency?"

As bridge tolls have soared in recent years to pay for the new span, commuters expect "honesty and not obfuscation," said Sen. Mark DeSaulnier, D-Concord, who chairs the Transportation and Housing Committee, at a press conference before the hearing.

Independent outside reviews of the bridge will be ordered as needed, he said.

Last week, officials from Caltrans, the Metropolitan Transportation Commission and the California Transportation Commission said they hope the decision on whether the bridge will open on Labor Day, as planned, can be made by May 29. The decision depends, in part, on how quickly a retrofit can be completed to replace the function of bolts that broke in March. The bolts were meant to secure seismic devices on the eastern pier of the new suspension span.

Caltrans and other agencies have been struggling to determine a fix for the broken bolts, which had failed some quality tests.

They have been set back by a series of revelations that cast doubt on more than 2,000 other parts installed into the bridge.

The steel parts combined extreme hardness and strength with galvanization, a coating process meant to protect against corrosion. That set of characteristics promotes susceptibility to hydrogen contamination that can cause cracks under stress.

Dougherty defended the use of the bolts.

"There was experience in successfully using these bolts," he said. "It was a decision that was made eyes wide open." He said that in retrospect, additional testing might have revealed the brittleness problem.

Among the most worrisome of the suspect parts are more than 400 steel rods at the base of the suspension bridge tower, important for stability in a big earthquake.

They were treated in hydrochloric acid to prepare their surfaces prior to galvanization. That "pickling" process, which increases the likelihood of hydrogen-related brittleness under stress, was banned by Caltrans but somehow overlooked in the quality control process.

The rods have not yet shown any signs of breakage, but their location – embedded within concrete at the base of the tower – makes them hard to examine.

"I suspect that the replacement of these parts would be a tremendous ordeal," Arthur Huckelbridge, an engineering professor at Case Western Reserve University and an expert on seismic issues for bridges, said in an interview. Testing with ultrasound and other "nondestructive" methods might be able to detect breaks in rods, he said.

Part of the challenge with the rods is that under tension, hydrogen can migrate within the steel to promote cracking. But Brian Maroney, chief engineer for the bridge, said at the hearing that because a quake lasts no more than 90 seconds, such migration would not have time to take place.

Thomas Devine, an engineering professor and metallurgy expert at UC Berkeley, said in an interview that "the inconvenient truth" is that such breaks are possible during a large quake.

They depend on two unknowns – the amount of hydrogen contamination in the steel and whether corrosion from water contamination might have added additional hydrogen – along with the degree of seismic stress, he said.

Those factors should be possible to model, Devine said, supplemented by additional lab tests.

Steve Heminger, executive director of the Metropolitan Transportation Commission, said last week that all of Caltrans' judgments about the suspect bolts would be reviewed by the agency's peer-review experts and the Federal Highway Administration.

"With all due respect to the feds, I think you need a thorough, arm's-length review," DeSaulnier said at the press conference, citing an earlier federal review of the Bay Bridge tower foundation that uncritically supported Caltrans' positions.

A background paper provided by the committee suggested that such a review panel might be assembled from "a cadre of University of California professors" or a nonprofit think tank.

The Bee recently reported defects in 33-foot-long, 4-inch-thick welds, essential for seismic safety, at the base of the bridge tower.

DeSaulnier asked Caltrans officials to report on the condition of those 20 welds and about whether the agency planned an independent review of their repair.

Maroney said that for the past nine months, the welds had been examined by Caltrans and its contractors, and some are being repaired as the evaluation continues. "Everybody's welcome to look over our shoulder – 110 percent transparency," he said.

Yet Caltrans has so far refused to provide details on the weld problems, despite repeated requests from The Bee and questions from public officials.

Senators also addressed a recent report by the state auditor that criticized Caltrans for failures in an agency unit that was involved in falsifying tests meant to verify the quality of foundations for bridges and other freeway structures.

The auditor said employees falsified data in 11 cases. Caltrans analyzed the suspect structures and said they were safe despite the lapses.

The audit also criticized Caltrans for widespread record-keeping problems that cast doubt on other work, and for management failings involving the test unit supervisor, who was found to have misappropriated building materials and later was fired.

The Bee reported those problems and others in articles published since 2011.

Call The Bee's Charles Piller, (916) 321-1113. Follow him on Twitter @cpiller.

© Copyright The Sacramento Bee. All rights reserved.

Read more articles by Charles Piller



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