|
Post by Alexis Kasperavičius on Aug 8, 2013 22:41:49 GMT -8
Dwight's last picture troveDwight, I think I can speak for all of us in expressing our sincere appreciation for the incredible amount of work you've put in to this project and for the many thousands of pictures posted. Fans of the Expo line around the world feel like they know what's going on through your pictures. They have been used by many publications, by council members, by Metro, and even the contractors to show progress on the line - making this one of the most, if not the most, closely followed public works rail project in my memory. You and your wonderful pictures will be sorely missed and I wish you good luck in your move and new job in Ohio!
|
|
|
Post by metrocenter on Aug 9, 2013 6:15:21 GMT -8
I'll second that. Dwight, your pictures have been a huge treasure, especially for those of us who only get out to the Westside periodically.
Thanks a lot, and best of luck on your big move!
|
|
|
Post by Gokhan on Aug 9, 2013 10:54:17 GMT -8
You brought more liveliness to the Expo Party, expolinefan. Best wishes to you on your new job!
|
|
|
Post by Alexis Kasperavičius on Aug 9, 2013 12:45:51 GMT -8
Dwight passed on a couple of things he found out while taking his pics:
Metro got their request approved for concrete sleepers (rail ties) for special track-work, turnouts and switches instead of creosote soaked wood (which was used on Phase I)
Track installation will start very soon. Welding is ongoing and prep work is almost done at Stewart street rail pile, soon to move on to a pile at Westwood, then another at 17th St.
Apparently the work consists of welding 14 sections of 80 ft track into one working length of 1,120 feet - ready for installation, the final weld being done during installation.
|
|
|
Post by RMoses on Aug 9, 2013 14:39:28 GMT -8
Updates will be missed, will try to contribute with some SM pix.
|
|
|
Post by culvercitylocke on Aug 9, 2013 16:18:21 GMT -8
yeah, we'll really have to step it up with the poster contributed photos. Dwight had some really good photos up, I can't believe how far along the Olympic Bridge is, and the Venice Bridge seems to be progressing really rapidly. And falsework will be going up for the spans over Sawtelle and Motor soon, I presume?
How much still needs to be done for the Pico crossing spans? will the horizontal span be built into the falsework spanning the street or will that be a separate piece on top of the square columns and then the falsework on top of that?
Dwight posted a chart earlier in the year that broke down each section of the line by all the phases of construction, someone ought to update that. :-p
|
|
andop2
Junior Member
Posts: 70
|
Post by andop2 on Aug 12, 2013 12:15:57 GMT -8
How much still needs to be done for the Pico crossing spans? will the horizontal span be built into the falsework spanning the street or will that be a separate piece on top of the square columns and then the falsework on top of that? Dwight posted a chart earlier in the year that broke down each section of the line by all the phases of construction, someone ought to update that. :-p I'm sorry I don't remember the source (probably Dwight?) but I believe the same falsework girders used for the Olympic/Cloverfield bridge will be used for the Pico span. I believe the Olympic/Cloverfield falsework will be coming down soon, and the girders can be moved to begin Pico. Does anyone else recall this?
|
|
|
Post by Gokhan on Aug 12, 2013 12:21:47 GMT -8
Gokhan, Is there some reason that you stopped posting pictures of the Venice falsework? I have gone into complete transit picture withdrawal since Dwight left town. Though it is my understanding he will be back for a couple days for one final orgy of visual documentation. Can't wait RT Yes, I'm returning from my vacation this week. For Mr. Toe and others, Venice Blvd bridge formwork and rebar work is nearing completion. You can see how thin the walls of the empty box structure ("stems") that will carry the bridge deck are. Expect concrete pour in a few weeks. Looking west: Looking east: Looking northeast: Looking southwest: Looking south:
|
|
|
Post by Gokhan on Aug 13, 2013 10:20:36 GMT -8
Clarington Ave TPSS. So much work needed for these: There is still a gap in the wall for truck access across the street: Looking west from Durango Ave to Bagley Ave. Note the 17-ft-wide bike and pedestrian multiuse path on the north side, which will cross the tracks to the south side at Bagley Ave: Looking east from Durango Ave to Venice Blvd abutment:
|
|
|
Post by Gokhan on Aug 13, 2013 10:27:09 GMT -8
Anonymous sources told me that the Pico Blvd bridge western half has been delayed because of problems in two of the foundations (7R and 8L). The subcontractor who did the foundations (Hayward-Baker) is working on them to fix them.
|
|
|
Post by Gokhan on Aug 15, 2013 8:40:50 GMT -8
Status of the Venice Blvd Bridge as of this morning:
|
|
f ron
Full Member
Posts: 222
|
Post by f ron on Aug 15, 2013 14:33:53 GMT -8
|
|
|
Post by Gokhan on Aug 18, 2013 17:01:41 GMT -8
Venice Blvd Bridge concrete pours are starting tonight at 9 pm according to the calendar. Once the concrete cures (probably after a few weeks in this case), they will do posttensioning with steel cables. Expect the forms to come off and falsework to come down perhaps in late September or sometime in October.
|
|
|
Post by roadtrainer on Aug 18, 2013 19:51:17 GMT -8
Someone said that the stems and sofits were thin. Is this just an illusion? If its thin how's it going to hold the weight of the train? What if they decreed to use some Breda trains on this route? With them being heavy wont it crack the bridge resulting in bridge collapse? BBI built the first part of the bridge , why would they compromise? And built it so thin?
|
|
|
Post by Gokhan on Aug 18, 2013 20:14:52 GMT -8
I am pretty sure they are thick enough to carry the heaviest Breda P2550's with a thousand people in them.
|
|
|
Post by Gokhan on Aug 19, 2013 8:39:46 GMT -8
Venice Blvd Bridge concrete pouring is going fast.
|
|
|
Post by Gokhan on Aug 19, 2013 11:28:01 GMT -8
I am pretty sure they are thick enough to carry the heaviest Breda P2550's with a thousand people in them. It could easily take this -- no worries:
|
|
|
Post by culvercitylocke on Aug 19, 2013 11:30:50 GMT -8
Considering how long it seemed to take for utility relocation and for Balfour Beatty to construct the columns, I'm sort of blown away at the seemingly rapid progress on the Venice bridge. On the other hand, I'm not encountering the bridge every day on my commute anymore so I guess my perspective is a little skewed by that.
Has work started under the 405 yet for the segment between Sawtelle and Sepulveda?
|
|
|
Post by darrell on Aug 19, 2013 11:45:50 GMT -8
Has work started under the 405 yet for the segment between Sawtelle and Sepulveda? The Sawtelle east abutment and Sepulveda west abutments are done and Sawtelle is to be closed beginning this Wednesday night for falsework installation, but I haven't noticed anything in-between. Just updated by Expo: The closure of Sawtelle will begin Sunday night.
|
|
|
Post by darrell on Aug 19, 2013 11:53:08 GMT -8
Someone said that the stems and sofits were thin. Is this just an illusion? If its thin how's it going to hold the weight of the train? What if they decreed to use some Breda trains on this route? With them being heavy wont it crack the bridge resulting in bridge collapse? BBI built the first part of the bridge , why would they compromise? And built it so thin? The bridge spans are engineered as box girders - the bottom surface ("soffit") is in tension, the top surface is in compression, and the sides ("stems" or "stem walls") are there to separate the top and bottom (like the vertical web of an I-beam separates its top and bottom flanges). The tension cables embedded near the bottom of the side walls help the tension strength of the concrete (which is good at compression but not so good at tension, much better with all the rebars). You only want these surfaces to be thick enough to serve their function to keep the weight and cost down. California leads on engineering cast-in-place reinforced concrete bridges that are earthquake-resistant.
|
|
|
Post by Gokhan on Aug 19, 2013 11:58:38 GMT -8
The bridge spans are engineered as box girders - the bottom surface ("soffit") is in tension, the top surface is in compression, and the sides ("stems" or "stem walls") are there to separate the top and bottom (like the vertical web of an I-beam separates its top and bottom flanges). The tension cables embedded near the bottom of the side walls help the tension strength of the concrete (which is good at compression but not so good at tension, much better with all the rebars). You only want these surfaces to be thick enough to serve their function to keep the weight and cost down. California leads on engineering cast-in-place reinforced concrete bridges that are earthquake-resistant. Once they pull and tension the posttensioning cables, the bottom (soffit) will be under compression as well. Reference: everything you want to learn about concrete in one pageThe brief encyclopedic reference explains why you need rebars, how tensioning concrete works, and other fundamentals of concrete.
|
|
|
Post by Gokhan on Aug 19, 2013 13:24:55 GMT -8
Note that once the soffit and stems of the Venice Blvd Bridge are constructed, they will still need to construct the deck and posttension the concrete.
Balfour Beatty Infrastructure, Inc, will not install anything on the bridge. Once the bare structure is finished, Skanska/Rados will take over to install the utilities, rail, and OCS. The handover will take place sometime late this year.
|
|
|
Post by roadtrainer on Aug 19, 2013 18:20:38 GMT -8
I am pretty sure they are thick enough to carry the heaviest Breda P2550's with a thousand people in them. 8-|Well can you talk to someone to see if it fact or fiction?
|
|
|
Post by rubbertoe on Aug 19, 2013 19:49:10 GMT -8
Note that once the soffit and stems of the Venice Blvd Bridge are constructed, they will still need to construct the deck and posttension the concrete. Balfour Beatty Infrastructure, Inc, will not install anything on the bridge. Once the bare structure is finished, Skanska/Rados will take over to install the utilities, rail, and OCS. The handover will take place sometime late this year. Gokhan, From your earlier picture, it looked like the wood panels on the inside of the stem could be pulled off and put between the stems like they did for the Cloverfield bridge to support the deck pour. Do you know if they plan on doing that? That sure seems to speed things up and saves a bunch of lumber too. RT
|
|
|
Post by Gokhan on Aug 19, 2013 20:41:09 GMT -8
I am pretty sure they are thick enough to carry the heaviest Breda P2550's with a thousand people in them. 8-|Well can you talk to someone to see if it fact or fiction? No worries -- you can drive your bus safely under the Venice Blvd Bridge. Metro doesn't sign off on bridges unless they meet its specs. In fact, after the Breda P2550 LRV fiasco in which they turned out to be too heavy, Metro asked Expo to do a change order that cost Expo millions of dollars in order to redesign the La Brea and La Cienega bridges stronger so that they could carry the Breda P2550's.
|
|
|
Post by Gokhan on Aug 19, 2013 20:42:09 GMT -8
Note that once the soffit and stems of the Venice Blvd Bridge are constructed, they will still need to construct the deck and posttension the concrete. Balfour Beatty Infrastructure, Inc, will not install anything on the bridge. Once the bare structure is finished, Skanska/Rados will take over to install the utilities, rail, and OCS. The handover will take place sometime late this year. Gokhan, From your earlier picture, it looked like the wood panels on the inside of the stem could be pulled off and put between the stems like they did for the Cloverfield bridge to support the deck pour. Do you know if they plan on doing that? That sure seems to speed things up and saves a bunch of lumber too. RT I don't know and I was wondering how they would build the deck.
|
|
|
Post by darrell on Aug 20, 2013 8:25:01 GMT -8
These two Phase 1 photos of the Flower Street bridge over the Harbor Freeway show the forms for its deck before it was poured: 10/24/09 - The stem walls are done, and deck form panels are stacked up; note their beveled edges. 11/13/09 - Look for the plywood forms showing through the rebar.
|
|
|
Post by Gokhan on Aug 21, 2013 11:32:29 GMT -8
|
|
|
Post by Gokhan on Aug 21, 2013 21:26:56 GMT -8
Motor Ave falsework installation has started and the street will be closed 7 pm - 6 am for a week, starting tomorrow. I am guessing they will build this bridge in no time. The retrofitted abutments are looking kinda weird though.
|
|
|
Post by bobdavis on Aug 21, 2013 22:32:42 GMT -8
Regarding bridge strength on the Expo Line: I'm not sure what the actual safety factor is, and I might be hesitant to approve running Union Pacific 4014 (a.k.a. Big Boy) above Venice Blvd., but I doubt that any foreseeable LRV would approach the weight limit. When the Gold Line modifications to the old Santa Fe bridge over the Pasadena Freeway between Highland Park and South Pasadena were made, I don't think the Breda cars were even on the drawing board, but dozens of them cross it every day.
|
|