Thursday, April 26, 2018

LACMTA unveils TBMs for Purple Line Extension Project

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LACMTA unveils TBMs for Purple Line Extension Project LACMTA

The Los Angeles County Metropolitan Transportation Authority (LACMTA), elected officials and community members gathered April 25 for a ceremonial naming and unveiling of the tunnel boring machines (TBMs) that will dig twin four-mile tunnels under Wilshire Boulevard for the Purple Line Extension Project.



Representatives for LACMTA, elected officials and community members attended the ceremony, which was held in L.A.'s Mid-Wilshire District. Subway tunneling is expected to begin later this summer, officials said.

LACMTA Board Chair and Los Angeles Mayor Eric Garcetti awarded TAP Cards and other prizes to students who won contests to name the TBMs and create illustrations for the TBM tail shields.

The names "Elsie" and "Soyeon" were selected from a winning entry submitted by Fairfax High School student Marianne Gutierrez. Soyeon is Korean for "bright" and "beautiful" and was named after female astronaut and mechanical engineer Yi Soyeon.

Elsie was named after Elsie Eavers, the first female to be elected as a member of the American Society of Civil Engineers.

Lauren Park, a third-grade student from Palm Crest Elementary in La Canada who also goes to Prism Art School in Koreatown after school, won the art contest. Her illustration portrayed her ideal community, which included Purple Line Extension service.

LACMTA said it would issue commemorative TAP cards featuring the illustration at 7th Street/Metro Center, Wilshire/Vermont and Wilshire/Western Purple Line Stations starting April 26.

"I'm proud to introduce our two newest Angelenos — Elsie and Soyeon — who embody the ambitious, resilient spirit of Los Angeles," Garcetti said. "Their work will bring us one step closer to realizing an integral part of our transportation future — a 25-minute subway ride from Downtown to the Westside."

LACMTA has received the cutterhead and shield for its TBMs, which are now staged at LACMTA's Wilshire/Fairfax station construction yard.

TBMs will be assembled at the Wilshire/La Brea station site and will initially travel east to Wilshire/Western in Koreatown. Parts of the TBMs will be retrieved from underground, with the rest moved back to the La Brea Station through the new tunnel.

The TBMs will then be reassembled and relaunched west to Beverly Hills as part of the first construction segment. LACMTA contractor Skanska, Traylor Shea, a joint venture, is constructing this portion of the project.

"The Purple Line Extension will be a game changer for the entire L.A. region," said LACMTA CEO Phillip Washington. "We are working aggressively to provide fast, frequent, reliable subway service between our county's two largest employment centers. This high-priority transit line is part of a much larger countywide transportation building boom that will create an infrastructure inheritance for future generations of Angelenos."

The TBMs are manufactured in Germany by Herrenknecht AG. The machines weigh approximately 1,000 tons, are 450 feet long and are 21.5 feet in diameter.

The TBMs will advance about 60 feet per day once digging begins, and twin tunnels will be separated from each other by about 16 feet of soil.

Tunnels will be about 50 to 70 feet deep, though some areas will be deeper. TBMs will tunnel five days per week, 20 hours per day and take roughly two years to mine both subway tunnels, officials said.

The Purple Line Extension Project is a nine-mile subway project that consists of three construction phases. The project will extend LACMTA Purple Line service farther west from Koreatown to West L.A.

The project will add seven new stations, officials said. The first subway segment is set to be operational in 2023. When it is completed in 2026, the entire subway extension is expected to serve 59,000 riders daily.

The project was funded by Measure R and accelerated by Measure M, the two most recent sales tax measures approved by voters for transportation improvements in Los Angeles County.