|Bid Date||August 25, 1998|
|MOWAT CONSTRUCTION CO.||(425) 398-0205||10,284,096|
|DILLINGHAM CONSTRUCTION NA||(925) 847-7027||10,555,695|
|SHIMMICK CONSTRUCTION CO.||(510) 293-1110||11,022,500|
CALTRANS TOLL BRIDGE RETROFIT PROGRAM ADDRESS
The Caltrans District 4 Office is located at 111 Grand Avenue, Oakland, CA 94612. The mailing address is P.O. Box 23660, Oakland, CA 94623-0660. The Toll Bridge Retrofit Duty Senior telephone number is (510) 286-5549, and the fax number for Contractor's inquiries submittals is (510) 286-4563
1) Would contract plan electronic files be available to contractor?
Contract plan electronic files will not be available to Contractors.
2) Coastwise trade determination for qualified barges.
"A non-coastwise qualified barge may be used as a moored stationary work platform within the territorial waters of the United States without violating the coastwise laws, provided that it transport neither passengers nor merchandise while under tow between coastwise points." Contractors have to get all the appropriate permits from the US Coast Guard.
3) Does the worker's compensation insurance for this project fall under the jurisdiction of the United States Longshore and Harbor Worker Act/or the Jones Act?
The Jones Act (46 U.S.C. & 13 et seq.) applies to seamen and shipping and does not relate to construction workers on the bridge. The Longshore and Harbor Workers' Compensation Act (33 U.S.C. & 901 et seq.) applies to employees engaged in maritime employment. A federal court decision of the Fourth Circuit Court of Appeals has held that a construction worker employment in building a bridge over navigable water, designed to benefit both traffic and navigation, is engaged in maritime employment under the Longshore and Harbor Workers' Compensation Act. (LeMelle v. B.F. Diamond Const. Co.)(1982) (674 Fed2.d 296). Under California law (Lab. Code & 3700), every employer is responsible for being insured against liability to pay workers' compensation. That responsibility is incorporated into the Department of Transportation's (Department) construction contracts under the provisions of the Standard Specifications Section 7-1.01(A)(6) that requires the construction contractor to certify compliance with Labor Code Section 3700.
4) Does "Brg" mean "Bridge" ?
No "Brg" is abbreviation for "bearing". See Standard Plans B0-1, Bridge Details.
5) Section A-A on sheet 63 of 138. Are the anchors shown, existing or new? And if they are existing, how do I get more information on those anchors?
These anchors are new. The way to obtain the "As-Built" details is indicated on page 73 of the Special Provisions.
6) Reference sheets 105/138 and 115/138. Sheet 105 , detail "South Approach", indicates that pier 14 will have 2 new end diaphragms. Sheet 115 of 138 details are shown only for the new end diaphragm for the north side and no details were shown for the south side. Please clarify the existing and the new construction diaphragms details.
Only the diaphragm on the North side of the hinge adjacent to Pier 14 needs to be retrofitted.
7) On sheet 105 the solid line indicates retrofit needed as opposed to the dashed line indicating no retrofit. On sheet 115, the detail indicates doing only the North side diaphragm. Bid Quantity item 40 is 56 EA. Planned Quantity is 44 EA. (Sheet 92 of the project plans). Which quantities are correct? Bid Quantity item 41 is 12 EA. Planned Quantity is 24 EA. (Sheet 92 of the project plans) Which quantities are correct?
See Addendum No. 1
8) Special Provisions, Section 10-1.13, "Maintaining Traffic," Lane Closure Charts #1 & #2. At maximum lane closure time (NB & SB), a maximum of one traffic lane is allowed. In the project plans (sheets 21-33, Stage 1-5), the traffic plan (addressing Abutment 1) is shown reduced to two lanes in both directions. In the project plans (sheets 34-36, Stage 6) the traffic plan (addressing Abutment 19) is shown reduced to one lane. The traffic at each abutment will be the same. The requirements for a large working area are greater at Abutment 1 (due to the nature and complexity of the work) than at Abutment 19. The Traffic Control charts show an allowable reduction to one lane in either direction. The project plans should show the lane reduction at Abutment 1 to one lane.
Contractor will be allowed to close as many lanes as he/she is allowed in accordance to Lane Closure Charts 1 & 2 included in Section10-1.13, "Maintaining Traffic" of the Contract special provisions.9)In preparing our bid for the seismic isolators on the Benicia - Martinez bridge, we note two discrepancies in the plans and specifications. They are:
See Addendum No. 1
10) In the "Isolator Bearing Performance Criteria Table" in the plans there appears to be a conflict or error in the properties listed for isolator Type 3. Fmax is listed as 234 kips at 11 inches, the minimum yield stiffness is listed as 18 k/inch, and the minimum yield strength is listed as 85 kips. Assuming 0.5 inch for yield displacement, then:
Fmax= Fy + Kp ( 11 - 0.5 ) = 85 +18 ( 11 - 0.5 ) = 274 Not consistent with Plan value, 234 kips
EDC = ( Fy - Kp x Dy ) x 4 ( D - Dy ) = ( 85 - 18 x 0.5 ) x 4 ( 11 - 0.5 ) = 3192 Within 1.5% of Plan value 3237.
Based on these calculations, we believe the correct value for Fmax is 274 kips. Please response to this clarification request.
See Addendum No. 1
11) Reference sheet 108/138. Top left side of detail "PIER 14 END DIAPHRAGM", the existing C15x33.9 is to be replaced with C15x50. What type of connection (welding or bolting) is required to install the new C15x50 to the existing structure?
See Addendum No. 1
12) Proposition 209 impacts to the State contracting.
On November 3, 1997, the U.S. Supreme Court declined review of Proposition 209. This decision, in effect, upholds the constitutionality of proposition 209. This has not immediate impact on the State contracting. Therefore, in the meantime, there is no change to the MBE/WBE program in State contracting.
13) Refer to sections C-C/14 of 89 & D-D/21 of 89. There is an angle 8x6x7/16 which appears to be bolted to the existing steel below the new 1/2" plate. Please clarify the extent of this connection as it is not shown in any of the elevations (i.e. Length of angle, quantity & spacing of bolts...).
The details for the 8x6x7/16 angle shown in sections C-C and D-D can be found on the End Diaphragm Details Nos. 7 and 8 (sheets 112 and 113 of 138).
14) Spec. Section 10-1.20E (Temporary Deck Bridging) - Further information regarding this bridge is needed. The temporary bridge will need to be arched in some fashion to clear the new work. Therefore, the allowable Design Geometrics (vertical curves and horizontal curves, allowable bumps and roadway discontinuities, etc) are needed. What is the allowable reduced speed on the temporary bridge area? What are the additional sign requirements, if any?
We do not expect that Temporary Deck Bridging will require significant changes in roadway profile, or the need for unusual roadway discontinuities. In addition to Section 10-1.20E, the Contractor must comply with all other sections of the special provisions, including 10-1.13 and 10-1.32, and the Standard Specifications.
15) Reference Bottom Lateral Details No. 2 Sheet 68 of 89. Partial Plan shows modifications to the west side of the bridge only without any reference to the east side. We therefore assume that there is no work required on the east side of the bridge at Pier 18 in this regard.
The details on sheet 117 of 138 apply only to the west end of Pier 18.
16) We have serious concerns with regard to the constructability of the designed retrofit at Abutment 1. Specifically per spec section 10-1.13, the longest workable traffic window is 8 1/2 hrs. The liquidated damages for exceeding this time limit is $8,000 per every 10 minutes over, to a maximum of $158,000 per incident. In order to construct the intended retrofit, a minimum of 4 major construction activities must occur in separate construction windows.
Windows are delineated as follows:
a) Existing approach slab must be sawcut, broken out, removed and trucked off - site; foundation piles for the temporary decking system must be driven or drilled and then the temporary deck support beams and decking must be installed before traffic can be restored.
The workable window is 12 hours for at least one lane open and 8 hours for two lanes. Saturdays, Sundays and holidays have longer windows.Multiple shift work is permitted. Temporary bridging is intended to provide riding surface over the 84" CIDH piling if not completed during the construction windows. The contractor will have to shore up the opening if needed to avoid cave in.
b) 84 Inch diameter cast-in-drilled hole piling must be constructed by removing the temporary decking system; a large truck or crane mounted drill rig must be mobilized into the work area; a slurry recirculation system with large Baker storage tanks must be provided for; drilling and removing spoils to the specified tip; trucking, unloading and setting the reinforcing steel cage into the drilled shaft; tremie placing shaft concrete by pumping and recycling of the shaft slurry mix must occur; and finally the temporary decking system must be replaced.
See previous answer.
c) Pile cap and counterfort wingwalls must next be formed, poured, stripped and backfilled utilizing multiple traffic windows each time removing and replacing the temporary decking system.
See previous answer.
d) The final operation involves the reconstruction of the replacement approach slab. This must be done by removing the temporary decking system; placing and tying the reinforcing steel; placing and finishing the ready mixed concrete; and curing the newly poured concrete for a minimum of 6 hrs. per the spec. prior to restoring traffic onto the new concrete.
See previous answer.
All 4 of these major activities are in excess of 8 1/2 hours of work. In particular the C-I-D-H operation could be as long as 16 hours without interruption to get completed shaft. We also don't think Caltrans intends to allow an open shaft to sit from night to night or over a weekend before being concreted even with slurry or casing maintaining the hole. Additionally if you add in the time to make lane closures and set K-Rail per the staging plans the remaining work window is probably less than 6 hrs. None of these major activities can be accomplished in this time period. We see no other way to do the work than to assume we will exceed the allowable window and absorb the commensurate liquidated damages as substantial as they are. Is this how Caltrans intends for this work to be accomplished and if so are you prepared for the potential public relations nightmare which will occur with the expanded closure time. Please consider increasing the time window allotted by allowing earlier access or a multiple shift continuous closure on the weekend utilizing advanced public information signing and media alerts, etc.
See previous answer.
17) Refer to bearing replacement drawings 48-55 of 89. Please clarify the extent of the new bearing stiffeners required: i.e. Are they required at all girders? Are they required both near & far side of the girder? Are they to be full height of the girder? If so, please provide the girder depth and/or stiffener height required.
Clarification of the number, size and location of the bearing stiffeners is being provided on the revised plan sheet 129 of 138 included in addendum No. 2 coming up soon.
a) Stiffeners are required at all girders.
b) Stiffeners are required both NS & FS.
c) Stiffeners are full height.
The girder depths can be obtained from the AS-Built plans available from the State.
18) Reference Bottom Chord Lateral Bracing Plans Sheet 67 of 89. Partial Plan for Piers 2, 15 thru 18 is the only Plan to have the note: "Left side of bridge shown, right side of bridge opposite hand". Because this note is not called out at the other Plans for Piers 3, 13 & 14 and Abutments 1 & 19 our literal interpretation is that the lateral bracing is only performed at the left side of the bridge at these locations. If this interpretation in not correct please provide an amendment accordingly.
See revised plan sheet 116 of 138 included in Addendum No. 2 coming up soon.
19) Reference Drawings-U1, U2, U3, U4, U6, U7, U8, U9 & U10. Please verify that the 3.5" galvanized water line on Piers 3, 13, 14 and Abutments is 3.5" ID or 3.5" OD.
Standard practice is to refer to pipe sizes by ID.
20) Temporary Railing (Type K) is summarized per the required lineal footage on plan sheet 42 of 138. Although the indicated quantities match the quantities needed per stage and phase, these quantities do not account for the multiple moves of the K-rail needed each night work is performed in the indicated stage. In the three stages necessary for Abutment 1 retrofit recontruction. the commensurate K-rail could be moved out to detour traffic and back at the end of the work shift in excess of 33 additional times beyond the initial setup. Nothing in the plans or special provisions would preclude payment for this additional footage except for the 25% quantity increase adjustment. Please clarify.
Refer to the fourth paragraph, second statement of Section 12-4.01, "Measurement and Payment," of the standard specifications, which reads as follows: "If the Engineer orders a lateral move of such temporary railing, and the reposition is not shown on the plans, moving the railing will be paid for as extra work......." Contract plan sheets (Stage Construction) for this contract show all the multiple lateral moves of the temporary terminal section (Type K) needed during working hours. Therefore, the contract item for Temporary Railing (Type K) for this contract shall include compensation for all these daily lateral moves. No additional compensation will be considered. For lateral moves of temporary terminal section (Type K), see last paragraph of Section 10-1.17, "Temporary Railing.".
21) Bid Item #49 lists the estimated quantity as 11,300 SQFT. This seems to be about 10 times the actual quantity. If the larger quantity is correct, please clarify the extent of the work.
Spot blast cleaning and painting occurs at the following locations: Abutment 1 Expansion Joint, Abutment 19 Expansion Joint, Pier 18 retrofit, isolator Bearing details, Bearing Stiffeners, Splice plates at joints, End Diaphragms, Bottom laterals. The quantity listed in the Engineer's Estimate for this item is correct.
22) Bid Item #49- Is removal of existing coating with vacuum shrouded power tools an acceptable alternative to sandblasting.
No. The special provisions on page 122 require sandblasting in accordance with the provisions of Surface Preparation Specification No. 10, "Near White" Blast Cleaning, Although power tool cleaning produces surfaces that look like "near white" but are not necessarily equivalent to that called for in SSPC-SP10. The use of inorganic zinc rich primer necessitates the SP10 surface preparation.
23) Can we use mechanical splices where butt welding is specifically called for? See Section A-A on sheet 85 of 138 and Note 4 on sheet 89 of 138. Your construction department has told us that we will always have the alternative of using couplers instead of butt welding.
The plan sheets you mention appear to require butt welding. Since that is what is being asked for in the contract documents, that is how the bids should be prepared. If the Construction RE opts to make a change, he should do so with a CCO. If a change is to be made before bids open, it must be by addendum. Bid it according to the plans and specs unless an addendum is issued making the change.
24) The 1" stiffeners to be added to the existing girders for bearing replacement are to be welded by a fillet weld. Contract Plans sheets (97 thru 104) of 138 at the top. The size of this fillet is not called out. Please advise to the fillet weld size required for this connection.
Standard practice is to detail these welds as shown on the plans. The contractor determines the size of the fillet welds based on the thickness of the materials being joined in accordance with the Standard Specifications- 55-3.17 Welding.
25) Project Plan Sheet 91 of 138, Note 3 indicates, "Jacking loads at any one pier shall be applied simultaneously." Does this mean the designer plans for all six bearing at a specified pier are to be removed in a simultaneous or sequential operation in lieu of removing one bearing at a time at multiple pier locations? Is it the intent of the designer to have all 6 or 12 jack locations on a specific pier temporarily laterally braced, jacked up, blocked off and supported in one continuous operation?
Your interpretation of Note 3 on Plan Sheet is correct. All girders at a pier shall be braced, blocked, supported and then jacked simultaneously.
26) The Existing Restrainer Removal Plan Sheet 122 of 138 shows the planned removal of the cable restrainers both longitudinal and transverse at the indicated piers. No detail is provided for the replacement of these cable restrainers and in consideration of all the new retrofit construction it seems apparent that their replacement would not be necessary. The special provisions on page 125, Section 10-1.43, are not clear on whether only the hinge restrainers are reconstructed or all restrainers are reconstructed? If indeed only the hinge retrainers are reconstructed, can the existing cables and swaged fittings be reused in the reconstruction?
Existing restrainers are to be removed and disposed of. Existing cables and swage fittings cannot be reused . Existing restrainers will not be replaced. New restrainers will be installed at the hinge adjacent to Pier 14.
27) Do you have the list of the accepted suppliers for the seismic isolator bearings on this contract?
Yes. The suppliers name can be found in Section 10-1.28 of the Special Provisions, page 98, it lists the manufacture name, address, and phone numbers.
28) The structural steel work contemplated for the subject contract and also for the currently advertised major bridge projects in the Bay Area make reference in both the Contract Plans and Special Provisions to the term "Fracture Critical" member. For reference and example please refer to Contract 04-044024 Sheet 116 of 138, Note 3 and Sheet 119 of 138, Note 4, (note these are only two examples of extensive usage).
Referring to members as "Fracture Critical" requires conformance with Section 12 of AWS D1.5, Fracture Control Plan. Section 12.2.2 states the definition of a Fracture Critical Member (FCM) to be "members or member components are tension members or tension components of bending members (including those subject to reversal of stress) the failure of which would be expected to result in collapse of the bridge". It is respectfully very hard to understand that the failure of the WT6X20 shown in Section F.F Sheet 116 of 138 or the 1/2" and 1" plates shown on Section A-A Sheet 119 of 138 would cause the collapse of the bridge.
Stating that a member is Fracture Critical also means per Section 12.8 Contractor requirements of AWS D1.5, that the work be fabricated by a Contractor certified by the AISC as a Category III, major steel bridges, with Fracture Critical Rating Certificate.
This leads to a major point of this letter. I personally have checked with all of the steel fabricators who have done business with us in the State of California, and none have a Class III Certificate. I have also checked with the Caltrans material lab in both Berkeley and Los Angeles and they know of no Class III fabricators who are doing work in California for Caltrans.
Not only will none of the work contemplated in the Bay Area be done by a California fabricator, but given the amount of work in total- millions of pounds of in effect miscellaneous metal- the costs of the fabricated materials will be unnecessarily high. Additionally, it will benefit no businesses in California, and in conclusion, do a great disservice to the tax payers and businesses of California.
I would respectfully ask that the problem I am addressing be reviewed with a view towards common sense, practicality and the overall objective. In my opinion, what is shown and stated in the current Plans and Specifications is an unwarranted extreme.
In addition to the FCM/fabrication problem, there is another question on the subject contract that despite repeated verbal and written questions, goes unanswered. The work at Abutment 1, Sheets 57-64 of 138 requires that a temporary bridge of approximately 32' of length be constructed, i.e. Bid Item No. 1. Please note that the required span will necessitate a bridge, not a simple plate. Page 82, Paragraph 9 of the Special Provisions states that the temporary bridge surface shall not deviate more than 1/4" vertically from the existing roadway surface.
Referring to Sheets 57-64 of 138 it is obvious that the new work of extended reinforcing steel, approach slabs, asphalt paving, and the expansion joint will all be in direct conflict with the temporary bridge. It is impossible to construct the work contemplated in the time frames allowed in the Special Provisions. This is not a trivial problem, but given the traffic delay penalties, a question of major importance not only for constructability and penalty cost, but for public safety and inconvenience.
We are not the only contractor concerned. Referring to the Caltrans Internet Outreach program for the Toll Bridges, there have been several questions regarding the same issue, all of which have not been properly answered.
To say, "bid it as you see it" is an unacceptable answer and I respectfully request that an addendum be issued to answer this extremely difficult problem. In absence of a work wise solution or answer it would only seem fair that as the Contractor is required to place their estimate in escrow after the bid, the State should also place their plan for Abutment 1 in escrow.
Fracture Critical Members
The member WT6x20, shown in Section F-F Sheet 116 of 138, is a Main Carring Element. Also, these members are shown in the Diaphragm Assembly in Sheet 112 of 138 and 113 of 138. The WT6x20 Members are designed to transfer lateral EQ Load - Acting from the concrete deck mass to the new W8x67 strut and then to conc. Stopper blocks shown in Sheet 118 of 138. Failure of WT6x20 or any element of the steel stopper blocks will cause the bridge to move laterally and the bridge will become unseated.
For Fracture Critical Members, the requirement of AWS D1.5 and contractor requirements remains. The work will be fabricated by a contractor certified by AISC as a Category III. Caltrans' intent was not to limit this work to the State of California.