Contractor Inquiry Responses, California Toll Bridge Seismic Retrofit


04-043544

CONTRACTOR'S INQUIRY RESPONSES NO. 1,

MAY 7, 1998


APPARENT LOW BIDDERS
WEST COAST BRIDGE$ 15,628,360.00
CALIFORNIA ENG. CONST. AND TADROS JV.$ 15,911,240.00
GENERAL CONSTRACTOR$ 16,887,670.00


CALTRANS TOLL BRIDGE 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 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)Can barges be moored or tied off to the existing piers?

Structurally mooring is allowable to the pier but not allowable to the existing fender. Additionally, Coast Guard permit rules, regulations and conditions would govern over times and length that mooring is allowable.

5)Are drawings of the existing West Bay Bridge, including the Piers W2 thru W6 and their fendering system available for plan holders to acquire?

Yes, they are available at the Toll Bridge Duty Senior's Office located at the Caltrans District 4 Office at 111 Grand Avenue, Oakland, Ca 94612.

6)Special Provisions Section 3, 2nd paragraph, page 11 states: Each of the two bonds required in Section 3-1.02, "Contract Bond", of the Standard Specification shall be in the sum equal to 100 % of the contract price. The Proposal and Contract book contains page B-1, which state 50% only, please clarified.

See Addendum No. 1 for clarification. Special Provisions are correct.

7)Section 5-1.28 of Contract Special Provisions states: "The Contractor will not be allowed the use of any existing utilities on the bridge or within contract limits." May the Contractor pay for usage of existing bridge utilities from the owner?

No. The Contractor shall supply his/hers own utilities.

8)Can the Contractor bring utilities accross the abandoned pier?

Please contact the Port of San Francisco, who are owner of the pier.

9)Section 10-1.21 of Contract Special Provisions states: "Water from core drilling operations shall not be permitted to fall into the bay." Can this water enter the bay after fines or impurities has settled or been filtered?

The Contractor shall direct this inquiry to the San Francisco Regional Water Quality Control Board.

10)Section 10-1.16 indicates that the paint removal debris must be disposed of by the contractor at a Class 1 landfill. This section is silent on who will be considered the generator of this material. We are assuming that the State is the generator. Please confirm this assumption.

It is correct. The Engineer will be responsible for signing the shipping manifests.

11)On plan sheet no. 22 of 103, detail A contains a note stating: Placement of bars will require couplers of diamter no greater that 2-7/16". For 1-3/8" dia. H.S. threadbar conforming to the Special Provision Sect. 10-1.28 requirements-150 LSI Ultimate stress and requirements of ASTM: A722, the commercially available threadbar full-loadcouplers are manufactured to a 2.625" O.D. by DYWIDAG Systems Intl. and 2.500" O.D. by Williams Form Engineering Corp. Please advise as to whether the above referenced couplers manufactured by Dywidag and Williams will be acceptable for use on this project. If these couplers will not be acceptable, please provide name and data on an acceptable manufacturer's product.

Couplers with a diameter greater than 2-7/16 inch will not be acceptable for use on this contract. Please note that Williams Form Engineering does provide a coupler with an outside diameter of 2-3/8 inch. DSI also provides a coupler with a diameter of 2-3/8 inch.

12)Section 5-1.28 of Contract Special Provisions states: "The Contractor will not be allowed the use of any existing utilities on the bridge or within the contract limits." May the Contractor pay for usage of existing bridge utilities from the owner?

no.

13)Section 5-1.32 of Contract Special Provisions describes the submittal of approved final working drawings in electronic form (Microstation Version 5.0). Will the State provide the Contractor with CAD files of the original Contract Plans?

No. Contract plan electronic files will not be available to Contractors.

14)What Containment System (if required), is needed for Abrasive Blasting of existing concrete surfaces shown on the Contract Plans?

Refer to Section 10-1.22, "Abrasive Blast," and Section 10-1.16, "Existing Higway Facilities," of the special provisions.

15)Contract Plans does not show an end detail at the top of the pedestal for bundled 1-3/8" HS bars at Pier W2. Please clarify.

Refer to Section E-E and F-F on contract plan sheet 22 of 103.

16)Section 10-1.28 of Contract Special Provisions describes the requirement for grouting cored holes. In the case of vertical cores at Pier W2 (with depth up to 136 feet), can the grout tube be pulled up as the grout fills the hole or is it required to fill the hole completely prior to the removal of the grout tube?

Grout tubes shall be removed during grouting. Ref. Section 10-1.28 "Miscellaneous Metal (Bridge)," paragraph 8 second sub-paragraph.

17)What type of materials can be stored in the Cement Anchorage if any?

None.

18)Pier W5 shows access into the vault section for the construction of the interior jacket concrete. No access is shown for the same vault wall at Piers W3 & W6. Will access into Piers W3 & W6 be typical to the that shown at Pier W5?

Please refer to the as-built plans for existing manholes and access holes between existing vault cells.

19)How much load can be placed on the pier aprons?

It is the Contractor's responsibilty to determine the capacity of the existing pier aprons for the purpose of his operations. Attention is directed to Section 7-1.11, "Preservation of Property," and Section 10-1.16, "Existing Highway Facilities," of the Standard Specifications.

20)Can the Contractor erect a scaffold on the columns for bringing materials from the deck to the footings?

Modifications to the existing structure for the Contractors's operations may be allowed subject to the Engineer's approval. Attention is directed to Section 7-1.11, "Preservation of Property," and Section 10-1.07, "Cooperation," of the Standard Specifications.

21)Will percussion drilling be allowed as a core drill method for Item 18, Core Concrete (9")?

The Contractor shall determine the method of coring which will not shatter or damage the concrete adjacent to the holes.

22)What inspection procedures will be used by the Engineer while inspecting the cores from the coredrill work?

The methods of inspection shall be determined by the Engineer.

23)What is the minimum core sample that is to be provided for the Engineer? Length and diameter?

All concrete cores shall be inspected by the Engineer. The Contractor shall determine the length of the cores to be inspected. The diameter of the cores shall be determined from the size of the cored hole less cutting.

24)The contract drawings note that all "Drill and Bond Dowels" are to be epoxy coated. Page 90, section 10-1.20 of the special provisions states "unless otherwise provided, dowels to be bonded into drilled holes will be paid for as bar reinforcing steel (bridge). According to the specifications for the bar reinforcing steel (bridge), the reinforcing steel is not required to be epoxy coated. Please clarify whether the dowels are to be epoxy coated or plain and which payment item will be used for payment of the dowels for "Drill and Bond Dowels".

The contract plans (see sheet 67 of 103) call out all Drill and Bond Dowels to be epoxy-coated. The second paragraph of Section 10-1.20, "Drill and Bond Dowels," of the special provisions states that epoxy-coated dowels shall conform to Section 10-1.24, "Epoxy-Coated Reinforcement," of the special provisions. The seventh paragraph of Section 52-1.11, "Payment," of the Standard Specifications covers the payment of epoxy coating of reinforcement.

25)What surface preparation will be required for the existing steel and concrete surfaces against which concrete will be placed in the pier caissons?

For locations where existing concrete surfaces are required to be roughened to a 1/4" ampltude, as shown on the plans, please refer to Section 10-1.18, "Concrete Structures," of the special provisions. For all other existing concrete surfaces where new concrete will be placed, please refer to Section 51-1.13, "Bonding," of the Standard Specifications.

26)Will contractors be allowed to leave existing concrete removed from inside caissons in the bottom of the caissons?

No.

27)The As-Built drawings for the above referenced project do not indicate the size of the coarse aggregate used in the existing concrete. The information is critical to the core drilling scope of work. Please provide the coarse aggregate size used in the existing concrete.

The Construction Report dated September, 1934 indicates that the existing concrete used in the foundations is a Class A, 2-1/2-inch max. aggregate, 6 sack mix.

28)Can the forms used for the bolster concrete in the pier caissons remain in place?

No.

29)Is the latex paint at Pier 4 which is specified to be abrasive blasted lead based?

No.

30)Section 10-1.26 "STEEL STRUCTURES" of the special provisions require that steel fabrication shops be certified under the AISC Quality Certification Program, Category III. It is our understanding that specifying this is not Caltrans current policy. Is it required for this contract?

Yes, bid what is in the plans and special provisions.

31) Page 109 - The first paragraph under " Clean and Paint Structural Steel" says "All exposed new metal surfaces and connections to existing steel, except where galvanized, shall be cleaned and painted in accordance with....". Does this mean that the galvanized surfaces shall not be painted or shall not be painted in accordance with....?

The second paragraph under "PAINTING" says "All exposed galvanized surfaces shall be prepared and painted in accordance with section 59-3 "Painting Galvanized Surfaces" of the Standard Specifications and these special provisions,except that the abrasive blast and treatment of Vinyl Wash Primer shall not be applied.

32) Page 110 &111 - The second paragraph under "PAINTING" says "All exposed galvanized surfaces shall be prepared and painted in accordance.....". The 15th paragraph says After the total dry film thickness of undercoats has been applied, all exposed new metal surfaces (including galvanized surfaces), and undercoated existing surfaces, shall receive the following finish coats:" What does the term "exposed" mean? Exposed to view? Exposed to the weather?

Exposed to air.

33)Referencing sheet 58/103, Column Base Plans, What size access hole is there to access the pipe shear key work? How far is this access hole above the concrete deck?

Please refer to the as-built plans for existing manholes and access holes into tower legs.

34)Please check quanity for Item 23 -Epoxy rebar. If I included the #11 & #14 bars grouted in cored holes, my wt. is approx 736,000 lbs. This will inturn reduce the wt. of Item 22 by 464,000 +/- lbs. ref. Specials, pg 97 - Measurement and Payment.

The second paragraph of the subsection "Measurement and Payment," of the Section 10-1.24, "Epoxy-Coated Reinforcement," of the special provisions states that "Full compensation for grouting and bonding reinforcement in cored holes shall be considered as included in the contract price paid per pound for bar reinforcing steel (epoxy-coated)(bridge), and no additional compensation will be allowed therefor." This does not state that the #11 & #14 bars are epoxy-coated.

35)Are the cored & grouted #14 and #11 bars epoxy-coated?

No.

36)Is the intent to paint galvanized platforms at piers W3, W5 &W6. If it is, can grating be finish painted off site?

Refer to upcoming Addendum No. 3.

37)Is spot lead removal by vacuum shrouded power tools acceptable in place of sandblasting?

Refer to the first paragraph of the sub-section "CONTAINMENT SYSTEM," of section 10-1.16, "EXISTING HIGHWAY FACILITIES," of the special provisions.

38)Can the latex paint on the upper portion of pier W4 be removed by paint stripper of high pressure water in place of sandblasting?

No.

39)Spec page 90 calls for "clear curing compound" on upper part of pier W4. Would the State list acceptable products and coverage rates.

Refer to upcoming Addendum No. 3.

40)Reference is made to special provisions 10-1.22 "Abrasive Blast," and the Standard Specifications 90-7.01. S.P. 10-1.22 para. no. 3 indicates that the abrasive blasting will produce a surface with a "...uniform color...", while S.P. 10-1.22 para. no. 6 indicates that the abrasive blasting equipment will be closed circuit (i.e. vacuum blast) type (" removal shall be by a vacuum attachment operating concurrently with the abrasive blasting operation.."). Vacuum blasters employ a shroud which contains the spent abrasive and removed debris, and the shroud blocks the operator's view of the surface being blasted. As such, the operator is unable to determine what the finished appearance of the surface will be while the work is in progress. Given normal variations in density of the concrete, thickness of paint, operators technique, vacuum blasting of concrete provides a finish which is less than aesthetically pleasing in as much as the concrete is clearly marked with a triped pattern corresponding to the movement of the vacuum blaster. Additonally, S.P. 10-1.22 para. no. 4 indicates that the blasted concrete surface shall be sprayed with "..clear curing compound...". The lack of uniform appearance resulting from the specified means of abrasive blasting will likely be amplified by the application of any such material.

Please confirm that the striped pattern resulting from the specified means of abrasive blasting will be acceptable and that any amplification of the pattern from the subsequent application of clear curing compund will be acceptable. Addititonally, advise what type of curing compound is to be applied, as the special provisions do not elaborate on this matter and the Standard Specification indicate that such materials are designed for "all newly placed concrete..." (Ref. Std. Spec.), which this concrete is not.

Refer to upcoming Addendum No. 3.


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