Trolley Line Bridge Is Cracked, May Have to Be Torn Up and Rebuilt

One of the first major structures completed on the Long Beach-to-Los Angeles commuter rail project, a $1.9-million bridge, is badly cracked and may have to be partially torn apart for the construction error to be corrected.

Engineers for the Los Angeles County Transportation Commission, which is building the $750-million trolley system, acknowledged in interviews with The Times that a breakdown in their inspection and quality assurance program contributed to the mistake.

“The bottom line is our people should have caught it,” said Clyde Garrison, deputy project manager for Transcal, a large engineering and construction management firm hired by the commission to oversee the building of the rail line.

The problem became apparent last fall after a series of cracks, some up to 14 feet long, developed in the surface of the nearly completed rail bridge being built to span Compton Creek near the Artesia Freeway. The cracks appeared after tension cables through the structure were tightened.

Bars Wrongly Placed

Engineers for the commission and the contractor who investigated found that steel bars intended to give the concrete strength had been improperly placed, sharply reducing the required reinforcement of the deck where the trolleys will cross.

While officials said the bridge would not have collapsed because of the error, it could have deteriorated and buckled prematurely, requiring a major repair much sooner than should be necessary.

The cost of making the correction--which may require breaking out the concrete deck and rebuilding it--has not been determined. Garrison said it could run “a couple of hundred thousand dollars.”

“It’s not lipstick and rouge,” he said. “It’s a major retrofit.”

Who will foot the bill is unclear. Commission officials say the contractor will have to pay. “In my view, there’s no exposure” for the taxpayers, said Paul Taylor, deputy executive director of the commission who oversees transit construction. “The contractor is not going to get paid until he does it right.”

Builder Disagrees

But the president of PKB Construction Inc., the Arcadia firm that built the bridge, disagrees. “They had an inspector out there that had to approve the steel before the concrete was placed,” said Peter Boli. “We feel they are culpable in the situation.”

Although no agreement has been reached yet on how to fix the bridge, Taylor and Garrison insist the problem will not delay the scheduled 1990 opening of the 22-mile trolley line--the first link in a planned 150-mile system. Track is not scheduled to be placed across the bridge for six months, Taylor said.

Opinions conflict on how such a major mistake went undetected.

Shortly after winning the contract, PKB sought and received approval from the commission to redesign the bridge to save itself and the commission money. Rather than use prefabricated concrete girders, PKB proposed pouring the span in place.

The new design drawings were a “little ambiguous” on the placement of the reinforcing steel, Garrison said. The ambiguity was not caught in a review of the design by the commission’s engineers, he said, but he stressed that “it was not our design.”

Mistake in Field

The interpretation used in the field resulted in the reinforcing bars being set at the wrong angle and improperly spaced, Garrison said. The mistake was not caught by the contractor, or the commission’s three on-site engineers and inspectors.

The commission’s field engineer should have double-checked the plans to ensure that what was being built was what was intended, Garrison said. “It was an error in judgment,” he said. “There’s no other face to put on it.”

But the field engineer, Thomas H. Lee, said the problem was not apparent to those working on the site. “It wasn’t a function of me to review those calculations,” Lee said. “That’s why we have a design section, or a designer.”

Garrison insists that inspection and design-review procedures have been tightened to prevent a recurrence of such problems in later stages of building the line.

Woes Elsewhere

Shoddy construction has plagued a number of mass transit projects in other cities in recent years. Poor inspection and improperly poured concrete led to major problems in the building of Miami’s elevated MetroRail, where girders cracked and supports crumbled. In Detroit, many of the concrete girders in the downtown People Mover system had to be replaced after cracking.

Garrison denied that the Compton Creek bridge problem reflects any major deficiencies in the commission’s ability to ensure safe, efficient construction practices.

But Taylor said, “We take it as a warning to be more vigilant.”

While the construction error on the bridge has been known for months, members of the county Transportation Commission were advised of it only Wednesday. Jacki Bacharach, who chairs the Rail Construction Committee, said she had no details on what went wrong.