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Old July 2nd, 2017, 08:27 PM   #2641
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Here's a good video of the drive (north), I'd say the pass starts after Sunset Boulevard.

(On freeway signs in LA, anytime you see them saying "Los Angeles", they are indicating to Downtown Los Angeles. You might already be "in LA" but some signs point to some communities of LA like San Pedro, for example. )

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Old July 3rd, 2017, 07:05 PM   #2642
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Originally Posted by pesto View Post
A nice discussion but you may have over-estimated the ignorance in this thread.

Monorail is being looked at because there is a specific issue that makes surface or center of freeway rail transit difficult, namely the steepness of the terrain. Therefore tunneling or monorail are possible alternatives. Of course, the amount of traffic has to be considered as well; but here the assumption is that it is very high.

Some are rejecting monorail out of hand; but I believe that some of the arguments used against it (passenger change of line or modality) apply more or less equally to a change from a line going down the center of a freeway to a surface line or underground line.
I hope no one has took offense, in which case I sincerely apologize although I wasn't even referring to posts here: what upset me make instinctively turn up my nose at is the way the monorail proposal is formulate by Mayor Garcetti (at least, according to the Los Angeles Times, as reported by Jim856796), plus the “eager beaver attitude” shown by Bloomberg's columnist A. Minter here - I followed the link because Garcetti explicitly mentioned a specific monorail manufacturer (BYD), another highly suspicious thing.
Since you pointed out that monorail is a bęte noire for rail buffs, I humbly tried to prove that even an aprioristic negative reception could be justified by something other than bias and mere fanaticism.

And the debate in this thread has only made my wariness grow stronger: putting aside the total absence of any reference to how big the transport demand is, Mayor said as a main point that an above-ground train can’t traverse the pass because of the steep incline. However, the graph posted by Kenni seems to contradict him: most of the ascending slope (between mile 1,5 and the peak) is fairly uniform with an average gradient of 30‰, quite affordable for heavy rail transit, while the steepest descending section (between the peak and mile 7) is more challenging, with an average gradient of 50‰, but likewise it can be negotiate by standard modern tramcar and also by a specifically-made metro train (Napoli's M1 line, a conventional “heavy” metro, climb handily a maximum gradient of 55‰). Therefore, it seems that in thruth an above ground (elevated or at grade) LRT can traverse the pass following the 405 Freeway alignement “as it is”, and a HRT also could with some adaptations.
This doesn't automatically rebuts that a monorail technology might be less expensive to built or operate, or otherwise a better choice, but shows clearly that in the proponents reasoning there are at least two serious flaws. I would be a whole lot more well-disposed if the thing had been put in these terms: «We are considering a cheaper, easier above ground alternative to deep-bored HRT (or LRT, depending on how many passengers are estimated for this route) under Sepulveda Pass, and monorail (any monorail, not a specific brand) too is among the options». Conversely, the way they put the matter leads to think it's “just another Lyle Lanley's genuine, bona-fide, electrified, six-car monorail”.


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Originally Posted by Kenni View Post
I doubt it would be an elevated HRT, which would also be costlier than the alternative. What most are advocating for is tunneling under the mountains, which would be extremely expensive, just the soil and geological studies would cost a pretty penny.
It would be undoubtedly expensive, however I'm pretty confident that tunneling deep under a scarcely populated mountain needs rather less money than doing it under the dense core of the city, (where you have, moreover, to build some underground stations too), unless the geology is locally rather adverse.
At the same time, it's impossible - as I said - to state an above ground (= elevated, cuttings, embankments) rail solution would be costlier than a monorail line unless you specify the capacity.
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Old July 4th, 2017, 02:55 AM   #2643
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Originally Posted by Yak79 View Post
I hope no one has took offense, in which case I sincerely apologize although I wasn't even referring to posts here: what upset me make instinctively turn up my nose at is the way the monorail proposal is formulate by Mayor Garcetti (at least, according to the Los Angeles Times, as reported by Jim856796), plus the “eager beaver attitude” shown by Bloomberg's columnist A. Minter here - I followed the link because Garcetti explicitly mentioned a specific monorail manufacturer (BYD), another highly suspicious thing.
Since you pointed out that monorail is a bĂŞte noire for rail buffs, I humbly tried to prove that even an aprioristic negative reception could be justified by something other than bias and mere fanaticism.

And the debate in this thread has only made my wariness grow stronger: putting aside the total absence of any reference to how big the transport demand is, Mayor said as a main point that an above-ground train can’t traverse the pass because of the steep incline. However, the graph posted by Kenni seems to contradict him: most of the ascending slope (between mile 1,5 and the peak) is fairly uniform with an average gradient of 30‰, quite affordable for heavy rail transit, while the steepest descending section (between the peak and mile 7) is more challenging, with an average gradient of 50‰, but likewise it can be negotiate by standard modern tramcar and also by a specifically-made metro train (Napoli's M1 line, a conventional “heavy” metro, climb handily a maximum gradient of 55‰). Therefore, it seems that in thruth an above ground (elevated or at grade) LRT can traverse the pass following the 405 Freeway alignement “as it is”, and a HRT also could with some adaptations.
This doesn't automatically rebuts that a monorail technology might be less expensive to built or operate, or otherwise a better choice, but shows clearly that in the proponents reasoning there are at least two serious flaws. I would be a whole lot more well-disposed if the thing had been put in these terms: «We are considering a cheaper, easier above ground alternative to deep-bored HRT (or LRT, depending on how many passengers are estimated for this route) under Sepulveda Pass, and monorail (any monorail, not a specific brand) too is among the options». Conversely, the way they put the matter leads to think it's “just another Lyle Lanley's genuine, bona-fide, electrified, six-car monorail”.


It would be undoubtedly expensive, however I'm pretty confident that tunneling deep under a scarcely populated mountain needs rather less money than doing it under the dense core of the city, (where you have, moreover, to build some underground stations too), unless the geology is locally rather adverse.
At the same time, it's impossible - as I said - to state an above ground (= elevated, cuttings, embankments) rail solution would be costlier than a monorail line unless you specify the capacity.
MTA some time ago included monorail technology in the analysis it has requested from private sources so this is not new with the mayor.

I can't comment either way, but local engineers and transit officials have noted that modifications required due to steepness and local conditions would make rail over the mountain nearly as expensive as tunneling. Tunneling would provide some additional benefits in that both train and car traffic could be accommodated. Monorail is mentioned because it is believed to be much cheaper.

I don't have a sense for expected ridership although about 500k vehicles go through the pass daily and the west side is growing.
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Old July 5th, 2017, 12:40 AM   #2644
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First, I don't post as an advocate for monorail, which I know is a bęte noire for rail buffs. I am just pointing out choices.
I am neither a "rail buff" nor did I suggest you are a monorail advocate.

Quote:
To clarify a potential misunderstanding: a Pacoima to LAX monorail would not add to the number of transfers. If you wanted to go to, say, DT, Century City, Hollywood, Ktown, Beverly Hills, WeHo, etc., you have to change trains in any event; perhaps twice. Of course, monorail is a change of modality but that is not so unusual; it happens at Grand Central and Penn St. every day to say nothing of LA Union Station.
If you are talking about a monorail all the way to LAX, then this changes things somewhat. It still might offer fewer direct connections than some alternatives, but it would cover at least the most important hubs where transfers will be necessary anyway in most cases.

In this case monorail is not worse for users, only for the operators. There exist high capacity monorail examples around the world, but you are in a cage with very few potential suppliers. That is bad and potentially risky in a lot of ways. There are reasons after all why monorail systems are relatively rare and why even cities like Chongqing (where to build monorail if not there) have switched from monorail to heavy rail metro lines for most of the future metro expansion.

That said, if LA metro builds a proper high capacity monorail line of similar function for its users as heavy rail, I have no problem with it. If a transfer is intermodal or not, doesn't really matter from a user perspective if the modes are well integrated with each other which is perfectly possible for the combination monorail/traditional HRT.
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Old July 5th, 2017, 09:15 PM   #2645
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Quote:
Originally Posted by Kenni View Post
Here's a good video of the drive (north), I'd say the pass starts after Sunset Boulevard.

(On freeway signs in LA, anytime you see them saying "Los Angeles", they are indicating to Downtown Los Angeles. You might already be "in LA" but some signs point to some communities of LA like San Pedro, for example. )

That video said it was $1.1 Billion. Wasn't it nearer $1.6 Billion on a $1 Billion budget to put in that car pool lane?
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Old July 8th, 2017, 12:10 AM   #2646
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Fresh pics: first Regional Connector rail tunnel under Bunker Hill

Fresh pics: first Regional Connector rail tunnel under Bunker Hill from The Source

Final preparations for the tunnel boring machine (TBM) arrival at Flower and 4th streets in downtown Los Angeles are underway on the Regional Connector project.

This weekend, the Financial District intersection will be closed from 7 p.m. Friday, July 7,through Monday, July 10, ending at 5 a.m. This first closure (in a series of ten weekends) will allow crews to begin the process of installing the strand jack gantry crane that will be used to remove the cutterhead and shield portion of Angeli (the tunneling machine’s name) when tunneling for the first of the twin tunnels is completed.

In the meantime, here’s a fresh batch of photos of the tunnel between the future Grand Ave Arts/Bunker Hill Station near 2nd and Hope and 4th and Flower. To date, Angeli has dug 5,120 feet from the station with roughly 700 feet to go.

One big challenge with tunneling efficiently is quickly troubleshooting mechanical issues and efficiently moving the whole tunnel assembly line forward in the tunnel with all its support wiring, pipping and conveyor systems . In these photos you can see crews maintaining water lines, building temporary tracks and installing new tunnel ring segments.

After the TBM breaks through at 4th and Flower, the machine will be retrieved from below ground and the massive pieces will be transported by truck back to Little Tokyo. The TBM’s trailing gear will be sent backwards through the finished tunnel.

The cutterhead and shield will be lowered back into the ground and reunited with the trailing gear at the Mangrove Yard in Little Tokyo and the TBM will be relaunched to being digging the second tunnel by the end of the summer. The second tunnel is scheduled to completed by the end of 2017.

















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Old July 11th, 2017, 01:13 AM   #2647
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Originally Posted by LAYiddo View Post
That video said it was $1.1 Billion. Wasn't it nearer $1.6 Billion on a $1 Billion budget to put in that car pool lane?
I'm not sure about the figure, but I was always opposed to this waste of money. They might as well had put transit in the middle of the 405.
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Old July 11th, 2017, 01:15 AM   #2648
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SOME GOOD NEWS



Expo Line Reaches Ridership Milestone 13 Years Early
The light rail line between DTLA and Santa Monica now carries 64,000 weekday passengers.

According to Metro’s official ridership estimates, the Expo Line reached an impressive ridership milestone during the month of June. With a daily average of more than 64,000 boardings, Expo is attracting as many riders in 2017 as it was projected to have in 2030. The rail line, which connects Downtown Los Angeles to the Santa Monica Pier, has proven to be a major success with L.A.’s transit riders, despite complaints about the line’s speed and reliability.

Expo has outpaced projections in the past, despite concerns from some quarters about the fitness of rail technology to serve the former Pacific Electric right-of-way. Expo’s first phase, which terminated in Culver City, achieved projected 2020 ridership numbers in 2013, seven years early. The Reason Foundation in 2012 had previously said that the projection of 64,000 riders for the full build Expo Line “should be viewed with some skepticism.” The light rail line has experienced surging popularity since its six-mile second phase opened, and now has eclipsed that mark in just over a year.

FULL ARTICLE/SOURCE
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Old July 11th, 2017, 01:32 AM   #2649
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SOME GOOD NEWS

Expo Line Reaches Ridership Milestone 13 Years Early
The light rail line between DTLA and Santa Monica now carries 64,000 weekday passengers.

According to Metro’s official ridership estimates, the Expo Line reached an impressive ridership milestone during the month of June. With a daily average of more than 64,000 boardings, Expo is attracting as many riders in 2017 as it was projected to have in 2030. The rail line, which connects Downtown Los Angeles to the Santa Monica Pier, has proven to be a major success with L.A.’s transit riders, despite complaints about the line’s speed and reliability.

Expo has outpaced projections in the past, despite concerns from some quarters about the fitness of rail technology to serve the former Pacific Electric right-of-way. Expo’s first phase, which terminated in Culver City, achieved projected 2020 ridership numbers in 2013, seven years early. The Reason Foundation in 2012 had previously said that the projection of 64,000 riders for the full build Expo Line “should be viewed with some skepticism.” The light rail line has experienced surging popularity since its six-mile second phase opened, and now has eclipsed that mark in just over a year.

FULL ARTICLE/SOURCE
Can't say I am surprised. I called for this to be underground all the way since this is an obviously high demand route that will do nothing but grow (DT, USC, LAFC, Museums, Lucas, Crenshaw, DT Culver City, Sepulveda, SaMo). I wonder what other MTA lines look like in total and compared to projected.

I am also curious to see how much Purple attracts when it opens to Westwood in 2027 or so.
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Old July 11th, 2017, 01:59 AM   #2650
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No doubt the Purple Line extension will alleviate the numbers.

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Old July 14th, 2017, 06:00 PM   #2651
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Construction work on Crenshaw/LAX Line Pictures

From the Source:













Above are some photos taken over the last several weeks of work on the Crenshaw/LAX Line, the 8.5-mile light rail line with eight new stations that will run between the Expo Line and the Green Line. Metro is planning to open the project in the fall of 2019.
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Old July 16th, 2017, 02:11 AM   #2652
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Crenshaw Line Video

Video from CBS Los Angeles of the Crenshaw Line

CLICK HERE FOR VIDEO
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Old July 16th, 2017, 05:18 AM   #2653
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Old July 22nd, 2017, 10:19 PM   #2654
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Some new Crenshaw Line pictures

Some new Crenshaw Line pictures from their Facebook page


Openings to the northbound and southbound tunnels.


Expo Station box.


Frame for the cross passage excavation site.


Tunnel cross passage


Tunnel cross passage


Near LAX Airport


Expo/Crenshaw station box


Expo/Crenshaw station box
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Old July 22nd, 2017, 10:25 PM   #2655
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Metro Purple Line Updates

Metro Purple Line Updates, from Facebook:


Working on the ventilation for the future Wilshire/Fairfax station.


Close up of the deck that which supports the concrete decks that cars drive, buses drive on, pedestrians walk on, and bicyclists ride on.


Assembling the framing for the decking.


Excavator placing a mini excavator into the pit to continue clearing soil.


Installing sound wall panels on at the Ogden Yard.


Placing deck panel just past the Wilshire/Fairfax Intersection.


Placing beam during over the weekend.


Excavating under Wilshire Bl. That opening where the light is shining through leads to the center opening on Wilshire Bl between Sycamore Av and Orange Dr.


The Wilshire/La Brea Station will be 1,000 feet long. That’s 1 2/3rds as tall as the Seattle Space Needle or 1 1/3rd as tall as the highest point on the Golden Gate Bridge!
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Old July 27th, 2017, 08:59 PM   #2656
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New video: time-lapse of digging of first Regional Connector tunnel

New video: time-lapse of digging of first Regional Connector tunnel
from The Source



New footage from the Regional Connector project in downtown Los Angeles shows how the tunnel boring machine has completed building the first of two twin tunnels under the city center. Work on the mile-long tunnel started in February of this year in Little Tokyo and was completed last week in the Financial District.

The Regional Connector will link three existing light-rail lines (the Gold, Expo, and Blue Lines) and add three new underground stations in downtown Los Angeles between Little Tokyo and 7th/Metro stations. When done, the project will create two light rail lines — one will run between East Los Angeles and Santa Monica and the other between Azusa and Long Beach. The two lines will share five downtown L.A. stations and make travel to and through DTLA faster with fewer transfers.

Angeli, as the TBM is named, began her journey at the future Little Tokyo/Arts District Station and bore 5,820 feet to the retrieval point at 4th and Flower streets. Along the way she traveled through the future Historic Broadway Station (at 2nd and Broadway) and made an appearance at the future Grand Av Arts/Bunker Hill Station (at 2nd and Hope) earlier in the summer.

The tunnel runs primarily down 2nd Street, which means the TBM successfully dug beneath the existing Red Line subway — at its deepest point, the tunnel runs 100 feet below ground. Soil conditions were favorable as most of the tunneling occurred within the Fernando Formation, the bedrock found across much of the L.A. Basin. In total, approximately 65,000 cubic yards of soil were excavated.

With the first tunnel complete, crews will remove the TBM’s cutterhead and shield segments this weekend and send the machine’s trailing gear back through the finished tunnel. Angeli will undergo maintenance and be rebuilt in Little Tokyo where she will start work on the second tunnel at the end of the summer. The second tunnel is expected to be complete by early next year.

The remainder of the 1.9-mile underground alignment—from 4th Street to just south of 6th Street — will be constructed using “cut and cover” tunneling down Flower Street. As the name suggests, crews will dig a large trench which is then covered with concrete decking to maintain vehicle traffic on the surface. With the deck in place, construction work can continue below ground. Flower Street decking is finished up to 5th Street and will continue south later this summer.
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Old July 27th, 2017, 10:25 PM   #2657
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LA Metro's Regional Connector Project and High-Speed Rail

Another video showing the Regional Connector, partially funded by the California High Speed Rail Authority



The California High-Speed Rail Authority is partnering with LA Metro to improve connectivity in Southern California by helping fund the Regional Connector Transit Project in downtown Los Angeles. The Authority is providing almost $115 million to the $1.75 billion project that will connect Metro Rail’s Gold Line to the 7th Street/Metro Center with a nearly 2-mile underground light rail system.
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Old July 27th, 2017, 11:35 PM   #2658
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A Tight Tunneling Feat to Transform LA Transit

After snaking through a subterranean obstacle course of utilities, foundations, methane gases and various urban structures, the 22-ft-diameter tunnel boring machine (TBM) dubbed “Angeli” broke through to its termination point at 4th and Flower streets in downtown Los Angeles July 19. It marked a key milestone in the $1.7-billion, 1.9-mile Regional Connector project—the “missing link” that will connect existing rail lines for seamless rides throughout Los Angeles County.

Having completed the first of twin tunnels between Little Tokyo west to downtown in five months, Angeli will now be disassembled over the course of five weekends and brought back to the original launch site to begin the second tunnel this fall, says Gary Baker, project director with the Los Angeles County Metropolitan Transportation Authority (Metro). BIM-assisted design and Shape Accel Arrays—a system of wireless sensors—helped Angeli navigate through extremely tight tolerances and situations of very shallow cover.


Utilities Jungle

The tunneling is not even the toughest part of the job. “This is a utilities job,” says Richard McLane, chief mechanical engineer with Regional Connector Constructors (RCC), a joint venture of Skanska USA Civil West California District Inc. and Traylor Bros. Inc. “Tunneling is about 6% of the total project.”

Unexpectedly tough utilities challenges caused termination of an initial contract, and much of the remaining work was tacked on to RCC’s contract as a change order in 2016. The utility issues pushed the completion back by about a year to 2021 and ramped up the project cost from $1.4 billion. “The real impact to the project was the condition of the utilities,” says Baker. “The customary approach when constructing stations is to support the utilities from the roadway deck while excavating below. But the electrical utilities’ condition in some old parts of town was unsafe for crews to handle. We had to relocate and replace them.”

Construction sequencing also had to be restructured. “We were going to run the TBM through the cavern at 2nd Street and Broadway and then start mining again,” says Derek Penrice, a vice president with Mott McDonald, RCC’s designer. “We had to go back to square one” with design.

Instead of completely excavating the cavern for one of three stations, walking the TBM across it and then relaunching it, RCC decided to just tunnel through the area and go back to complete the second tunnel before completing the cavern, says Matt Antonelli, senior director of construction management with Metro.

That’s also the case for a sequential-excavation-method cavern—290 ft long, 58 ft wide and 36 ft tall—that will eventually serve as a crossover structure over the tracks, says Baker.

When excavation of that cavern commences later in the project, “it will be one of the largest excavations in LA,” says Penrice. “It will be in shallow cover underneath a storm drain and adjacent buildings.”


Tight Spaces

Angeli launched out of a 45-ft-deep pit in Little Tokyo, burrowing through an initial 400 ft of alluvium above the water table and only 5 ft of earth above it, says McLane. “Generally, you want at least one tunnel diameter’s worth above you. We had to supplement the low cover with soil backs to add more surcharge for the machine to tunnel under pressure. Then we had a 600-ft curve downslope. That was the roughest part.”

After that, the TBM tunnels through the Fernando formation, a local bedrock that is “generally pretty good for tunneling,” says McLane. But with only the one TBM, the team will have to repeat the initial launch through the shallow cover and alluvium.

The TBM also passes beneath the existing Red Line subway, past the historic Second Street Tunnel and close to batter piles for the 4th Street Bridge. In one case, the team had to figure out how to avoid several layers of tiebacks supporting the Bank of America basement. “TBMs don’t like to tunnel through steel,” notes Penrice. The team changed the initial Metro plan to create a 100 ft x 30 ft excavation, 70 ft deep, to cut out obstructive tiebacks.

“It would’ve been too disruptive to city traffic,” says Penrice. “We came up with a scheme to use a more limited 26-ft-diameter shaft, created a 10-ft-diameter tunnel and cut the tiebacks.”

BIM served as a useful tool to help designers size the shaft properly and excavate only as much as needed, says Penrice. “Then we filled the hole back up again with a low-strength material that the TBM could mine through.”

Underneath downtown streets, conditions are so constrained that at one point the twin tunnels will be only 4 ft apart, notes Penrice. “Ideally, you would like a tunnel diameter’s worth between them,” he says.

The tunnel design utilizes three types of precast concrete lining segments to accommodate different conditions, including depths of over 100 ft, shallower areas and a section of Little Tokyo that may undergo redevelopment and thus required extremely heavy lining, adds Penrice.


Monitoring Mission

A Shape Accel Array (SAA) proved instrumental in keeping Angeli on track as it passed under the shallow initial ground cover and through the dense web of underground infrastructure. A 400-ft-long array of accelerometers positioned just above the TBM measure movement and potential deformation or settlement, transmitting data to the team’s command center. “It sends automatic alerts if something is out of tolerance,” says McLane. Settlement generally must be no more than a half-inch.

The team also uses natural gas detectors to warn of naturally occurring methane gas. The danger of tunneling in Southern California is well-documented: 17 workers were killed in a methane explosion in a water tunnel in 1971 and another blast in 1985 destroyed a clothing store during the construction of Los Angeles’ first subway system. “That put a halt to tunneling in LA” for a while, says McLane.

However, only once so far has a sensor alert resulted in a daylong shutdown on this project, he says.

Angeli also has a history with Los Angeles, having built the Gold Line extension in the mid-2000s. The TBM then went to Seattle, building tunnels for the University Link light rail system. Each time, the TBM was reconfigured for each project’s specific needs; for the Regional Connector, it needed to navigate a 550-ft curve, says McLane.

The 1,000-ton, 350-ft-long TBM, which got its current moniker from a contest held among Los Angeles schools, will excavate approximately 130,000 cu yd by the time it finishes early next year.

The project will allow commuters to travel between Long Beach to the south and Azusa to the north—about 40 miles—and between East Los Angeles and Santa Monica to the west with seamless transfers among the Blue, Gold, Red and Green lines. Metro expects that 90,000 daily trips will be taken on the new corridor.

Metro is aiming for a December 2021 completion of the project and is in the midst of negotiations with the contracting team to consolidate a number of milestones and phases, says Baker. “We are hopeful we can finish this project” before the December deadline, he adds.









Aileen Cho from Engineering News Record
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Old July 31st, 2017, 09:17 PM   #2659
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I wonder how much momentum is lost due to the fact that Los Angeles will hold the Olympics eleven, rather than seven, years from now.
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Old July 31st, 2017, 10:51 PM   #2660
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I wonder how much momentum is lost due to the fact that Los Angeles will hold the Olympics eleven, rather than seven, years from now.
Though having the Olympics in 7 years might have accelerated a few projects, I think they are about at the limit of what they can finance now with so much construction or planned construction going on.

Having it in 11 years will have the benefit of having more infrastructure in place for the Olympics. Hopefully the Purple Line to Westwood will be done by then and Crenshaw Line extended to the Purple Line.
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