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tv   [untitled]    May 10, 2012 9:30am-10:00am PDT

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supervisor kim: good morning, and welcome to the transbay joint powers authority board of directors meeting on thursday, may 10. i apologize for my tardiness. roll call please. >> directors metcalf and sartipi are absent. madam chair, you do have a quorum.
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any communications today from any borders? seeing no new and old business, going to the executive director's business report. >> good morning, everyone. on april 263 received a letter acknowledging our status as the new member of the member program that caltrans has established to increase architecture in the bay area and public transportation. we were very honored to receive the award. we work very hard to facilitate small business entry into our projects, so receiving that award was really appreciated. we will hear an update in a moment on the construction progress, but i wanted to mention on the design, we are working to finalize construction documents by this fall. i wanted to give that the board of update on the bid we have
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issued. on april 3 we issued the grounding system did, and it will be due on may 17. we expect by may 14 to issue the grade structure as well. that is a large build. this would be do about july 7. i will have bought packages anbn that. >> thank you. just a little update on the packages we have on the street right now and the packages we are about to put out. maria mentioned we have put out two packages. one is geothermal piping, and the other is the grounding package. these are relatively small packages, but it is worth -- work we want to integrate with
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the work of the integration while they are on site. we have a layering of activity that is going on where the buck to shoring and excavatitress shn will be completed. the work of the grounding will go in, and the subcontractor will install a mud that slab, which is a new structural concrete slab at the bottom of the excavation. and that will be the structure that the subcontractor will come in and build the train box on top of. the geothermal package includes to being that will be part of the geothermal system. we are using the geothermal system to provide supplemental cooling and healing as a way to
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utilize the ground water or roundtable on top of the transit center as basically a large heat source so that we can run -- rather than having cooling centers, we can run at the warm water down below this lab. it will cool off in the moist earth underneath the mat slab and bring it back up. that is about $1.5 million. that is to install the tubing. also, the grounding package will be installed that will ultimately be tied into the electrical system beneath the mudslide, and then brought up along the shoring walls so they can be integrated into the exterior wall and come into the building.
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the larger package is the substructure package. this is the build out that the concrete portions of the train box. the mat slab at the bottom of the building, and then the concrete walls that come up the perimeter of the trained box, as well as the structural systems of the platform level and slab of concourse level. i have an image on the next slide that will illustrate all of that. the other key component of the substructure is the waterproofing system that will go between the walls of the transit center in the existing shoring wall and will be placed on top of the mud slab before the installation of of we areba. just graphically to illustrate the substructure package, two weeks ago we closed the last segment of the shore in wall, so
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that it is part of the bse contract, and that is what allows us to enclose our excavation site, because the water level is so close, the shoring wall, which has a waterproofing compound in it already, and then it goes down into the old clay layer of soils and gives us an enclosed envelope or bathtub we can then dewater. the same high water table has an effect on the completed structure at the end where rather than having piles to support our building, because we are going so deep below grade, we need to have tie downs to resist uplift from the water table, trying to make the entire transit center flow. the excavation contract will be
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installing 1800 tie downs to give us additional resistance from the water table. >> are the tie downs little? >> they are like piles, but rather than rejoicing los down words, the grip it to the earth and soil to act as friction against up left. >> what about earthquakes? >> they do not have as much of an earthquake function. they do not have a specific role in earthquake forces. >> it is then at this point that the geothermal and grounded work will be installed before the
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contractor installs the mud slide. -- slab. the sub structure package will begin at this point with the installation of the concrete slab. it will capture and integrate the tie downs into the structure of the building. the contractor will build a concrete grilles. the slab of concrete in the walls coming up the perimeter. that will be the completion of the substructure package. the columns on the real concourse level up to the ground level is transition from a concrete structure to a still structure. although we talk about the superstructure package, which will be the next major package
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next fall, it actually starts at the royal concourse level, because we are stretching from -- switching from concrete construction to the steel construction of the building. that will be the substructure package we will put out next week. >> a few questions. the work that is going out now, the 1.6 grounding and the geothermal -- is there reason that was not included in the contract that is literally surrounded by the bse work. >> part of it is the timing of the development of the design. we are moving through the design process. it could be integrated, but we wanted to spend more time on the development of the geothermal system, so it was issued as a
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separate package. it is a specialty scope. we would probably be dealing with the same relatively small pool contractors. >> the tie downs, is it likely the number and actual steps of each one could vary based on actual conditions, and how you manage that? >> the contractor is given the performance characteristics -- it is performance-based in terms of the uplift, and each tied down that is installed it is tested. each one is tested so that we will be determining, and that they need to modify the design based on early test results, they can do that. >> that risk is all borne by the
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contractor? >> yes. >> is there any level of recycled content? >> we are not on the concrete at this point. one of the concerns with the below grade structure is shrinking and packagcracking. this tends to be more absorptive, which can lead to more cracking, which at this point we're not using recycled concrete. >> the last question. what kind of outreach have you done or will he do to get solicited interest in the $77 million package? >> we have already pre- qualified. we have five contractors pre- qualified for the package at
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this point. we have been doing additional of reach for small and disadvantaged subcontractors package. >> thank you. >> think you. ank you. >> of those pre-qualified, are they from the area or outside? >> they are all relatively large contractors, so they have significant local preferences, but because of the scale of this, they are contractors that work throughout california and nationally even. >> in addition to sending out weekly e-mails to the public community residents and businesses and anyone who wants to be on the mailing list, we also have a number of community etings to inform the public with what is happening. to report on that we have scott diehl. >> good morning, directors.
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we have two community are reached meetings. the first one will be on may 21 at 5:30 at tpja's offices. our program management team will present on the design of the facility and coordination efforts with caltrans. we are inviting all of the neighbors to solicit their input and feedback. that will be may 21 at 5:30 p.m. our second meeting this month is a regularly-scheduled community are reach meeting. also, we will provide an update on construction and the project. that means it is open to the public and an opportunity for members of the public to ask any questions they have on the project. the of a quick update, we did
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send out a quarterly newsletter. as we reported, we have initiated a quarterly newsletter that is going out to all of the supporters and everyone involved with the project. >> great. steve is out of town today, so bob will present the construction update. >> thank you. just to give you an update on the work that has occurred over the past month on the transit center project, we did have won it regrettable accident as last month -- one recordable accident this past month. an employee who was doing the shoring wall installation had a slip and fall and hit a piece of equipment as he fell, which
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resulted in him needing to get stitches, but not any lost time. that was an unfortunate incident, but fortunately a minor one. we did complete the work, which was the shoring wall construction. the weekend before that, fremont street was close to install the shoring wall, and that was the last section that went in, as i mentioned earlier. they have demobilized the equipment and more focused on the excavation process. now at over 280,000 craft hours completed today, with 20,000 over the past period. on tehe butress, we have completed 76 of the shafts,
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roughly one-third of the total. and we have been averaging 3 per week. the target when we started was 2.5. there was a learning curve at the beginning, but now the subcontractor is really hitting their stride on the progression. we are hopeful we may see an early completion, if we're able to maintain the level of productivity. in zone one, i will have images, but the contractor continues to install the bracing and wheeler system, as well as started construction of the trestle system that will be the working platform, not only for the excavation site contractor -- subcontractor, but the primary platform as direction of this do
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as we go forward. the utility side of things, the last of our utility contracts is working on a.w.s.s. work around the perimeter of the site, harvard and at mission streets. that work is ongoing now. -- howard and mission street. here is the timeline for the buttress shoring work. the buttress is about one-third of the way through production. i will talk to you about it in a little bit, but over memorial day weekend we will be installing the first of three traffic bridges. this one will be on first street, so that will be the roadway that carries traffic across the excavation site during the course of construction. those will continue through fremont street and labor day weekend and on veterans day
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weekend we will do feel streebee street. the excavation and racing is well under way on the west end of this site. supervisor kim: we have a question from a director. >> refresh my memory. it was supposed to be completed 2017? >> yes. >> when we start the actual construction of buildings? here you are still excavating them. and it bracibracing. >> the excavation will actually be complete at the west end of this site in zone 01 in 2013, roughly a year from now, a little less. that is when we will start constructing the substructure laup. the