‘Hammerhead’ crack fixes in limbo, delaying Oahu’s rail service

Eight of 21 cracked rail “hammerheads” along the city’s rail route appear to require more extensive — but undetermined — repairs, likely delaying Honolulu Authority of Rapid Transportation’s transfer of the transit system to the city for paid passenger service deeper into 2023.

The T-shaped hammerheads sit on top of rail posts to support rail stations and not the trains themselves. Cracks in 13 of them can be filled with epoxy to keep out moisture, with the goal of preventing further expansion of the cracks, Lori Kahikina, HART’s executive director and CEO, told the City Council’s Committee on Transportation, Sustainability and Health on Tuesday.

Federal, state and city engineers are reviewing a preliminary report from the engineering firm HNTB, the rail project’s “engineer of record,” on how to proceed. A final report is expected once all parties agree on a plan, likely sometime around the new year. Committee member Augie Tulba and Council Chair Tommy Waters told Kahikina they would like an update on the matter when the final report comes in, but no committee meeting is scheduled for December.

Previously, HART had expected to turn the system over to the city in the first quarter of 2023, in advance of beginning paid passenger service. Now two separate issues need to be resolved before the semi-autonomous city agency hand off the system: a fix for the cracked hammerheads and completion of systemwide testing to address any other problems.

“Probably all 21 (hammerheads) will have to have epoxy coating, but only eight will have to have something more substantial done,” Kahikina said. “Safety is paramount to us. … We’re waiting for the analysis to be complete on the hammerheads.”

Engineers from the Federal Transit Administration, state Department of Transportation and city Department of Transit Services still need to agree on how to address the cracks, Kahikina said. As of Tuesday the discussion was focused on post-tensioning, a method of reinforcing concrete that could involve “additional rebar,” Kahikina said. “It’s not just a matter of simple epoxy coating the cracks. Something more substantial will have to be done on those eight.”

The cracks were discovered in 2018 and were assumed to have been caused by concrete “shrinkage,” similar to what occurs in a new concrete driveway, Kahikina told the Council committee. But no one took precise measurements until June, Kahikina said. “It was done by visuals.” The measurements taken in June showed that the widened cracks were “more than what is typical of shrinkage,” she said.

The $9.8 billion project, as currently approved by the FTA, calls for a truncated route of 19 stations along 18.75 miles of track ending in Kakaako at the so-called Civic Center station. Kahikina on Tuesday called the Civic Center station the “temporary” end of the line — and she described the elimination of the Pearl Highlands parking structure a “temporary deferral.”

Discussions are underway to find new sources of funding to push the rail system to the previously planned Ala Moana Center station “and beyond,” including ways to provide service to North Shore and Central Oahu passengers, Kahikina said. “We’re fully committed to getting to Ala Moana and beyond,” she said.

Kahikina has pointed out that HART’s pillars and hammerheads were built separately, with the hammerheads later installed atop the pillars. Even with the hammerhead cracks in place, she said, the trains can be tested at speeds up to 55 mph because the weight of the trains is supported by the pillars — not by the hammerheads, which instead support the rail station structures. Each station is supported by two or three hammerheads, depending on the length of each station.

Engineering firm HNTB has concluded that the system is still structurally safe, and epoxy will prevent further water intrusion to “make sure the cracks don’t grow,” Kahikina told the committee.

In June and July crews from three mainland-based engineering firms — Consor, which represents the city’s Transportation Services; Wiss Janney Elstner Associates, a “third-party engineer” hired by HART; and HNTB — joined HART’s structural engineers in taking independent measurements of the cracks. HNTB and Wiss Janney Elstner Associates consulted with each other to reach agreement on baseline assumptions but otherwise conducted studies independently, Kahikina has said.

Kahikina on Tuesday was asked who will pay for repairs to the hammerheads: HART or builder Kiewit Hawaii.

Echoing HART’s plan following an embarrassing snag involving mismatched wheels and “frog” track transfer points, Kahikina said her focus is on fixing the hammerhead problem to get it resolved before focusing on who should bear the cost of repairs. “Those discussions will happen after the solution is done and after it has been implemented,” Kahikina told the committee.