A004_QuestAnswer.pdf

AG-0120-S-15-0021, Amendment 004, Questions and Answers

AG-0120-S-15-0021, Amendment 004, attachment pages

Questions Submitted after the Pre-Bid Meeting

Question1: Can we add a bolted field splice to the 70’ girders on Bridge Sites 2 & 3?

FS Response: Allowing an additional field splice in the girders at Thayer and Charley Creek bridges will not have negative structural or durability effects provided the following three criteria are enforced:

1) The splice is fabricated and installed as detailed on the project plans.

2) The splice locations are symmetrically located as dimensioned on the plans.

3) The camber shown on the plans is maintained and consistent for all girders.

Question2: The Steel Notes calls for hot dip galvanizing (single dip) for all steel. The girders for Thayer and Charley are 70’ +long. These cannot be hot dipped galvanized, single dip or double dipped. If galvanizing is required, where can these girders be spliced? If they are to be spliced, are welded splices required and if so, what are the inspection requirements? Are other coatings such as metallizing acceptable?

FS Response: The USFS is not considering welded field splices, and the additional field (bolted) splice permits shorter steel girder sections for a galvanization coating using the dip tank process (reference the response provided to Question1.). Should the Fabricator desire to fabricate 70 FT (+) girder sections to ship for the Site 2 and Site 3 bridges, and elect to use welded shop splices to accomplish this, these welded shop splices must comply with the provisions of the AASHTO/AWS D1.5 Bridge Welding Code (current edition) and the practices and procedures outlined by the American Institute of Steel Construction (AISC). Other coatings such as metallizing will not be acceptable.

Question3: The MSE wall infill is Select Granular Backfill 704.10. If we use the government furnished source do we have to do the testing according to 704.10 b,c?

FS Response: Yes the Contractor will need to provide passing test results for Select Backfill for MSE walls

Question4: Can you tell me what “Reference Staking 2” is?

FS Response: Method II Is found in FS Supplemental Specification 152.03(c ) however no slope staking notes or design printout information exists or any road reconstruction sections. No leveling or electronic design runs were done on existing roads because only additional widening, new lifts of rock and drainage structure replacements at the existing grades and elevations is needed. The purpose of even including Reference Staking pay item was to allow compensation for hanging clearing flags and referencing drainage locations for Contractors Quality Control purposes. Therefore, a bearing and distance to structures from an RP stake was all that was envisioned. If a Contractor wishes to establish any vertical control for their QC, Method 1 which is actual slope staking from existing ground elevations and inverts would be needed.

Question5: The loading for the abutment footings is not provided in the MSE section. The loading for the bridge is for an AASHTO 7th edition (LRFD), while the provisions state the MSE walls will be designed per AASHTO 17th edition (ASD). It does not appear that loading from the spread footing was taken into account in the design of the MSE walls.

FS Response: The FSSS, section 255, is replaced in its entirety with the attached (2 pages).

AG-0120-S-15-0021, Amendment 004, Questions and Answers

Question6: Can you provide the loading from the spread footings?

FS Response: Abutment SERVICE loads (per foot length of sill) are: 4535 lb/ft Live Load, 5762 lb/ft Dead Load. Dead loads include the abutment weight. Live loads are HL-93 truck + lane load and do not include dynamic load allowance (impact).

NOTE: The loads identified above as SERVICE loads are unfactored and are presented as a uniform load per foot length of the bridge sill at each abutment. It is expected that the successful bidder will install the MSE wall bid as per contract specification and as designed in the contract documents. Knowledge of the service loading is only relevant if the successful bidder desires to redesign the MSE wall for which a technical proposal will be required and evaluated for its acceptability to the government as a value engineered contract change proposal.

Question7: This project calls for relocating a utility pole permanently on the 1520 Road in Edna Bay.

What is the specific location of the pole and what is the distance it needs to be moved? Is it to be secondary or primary?

FS Response: The pole is clearly shown on site 1 plans. The existing pole is on property right-of-way boundary. The bridge will change the road alignment. The pole will have to be moved; however, the exact distance is unknown. It is expected that it will not have to be moved very far. It is believed that the pole is a primary telephone pole.

Questions regarding alternate bridge design: Please be aware that bridge manufacturers who provide quotations to Bidders on the “smaller bridges” (For example: those located at Sites 1 and 4.) that the quoted price should be based upon the design in the contract drawings and specifications which are compliant with the provisions of the AASHTO LRFD Bridge Design Specifications, Seventh Edition, 2014 U.S. Customary Units with all Interims. Should a bridge manufacturer elect to modify the contract design, they will be required to demonstrate that the proposed modifications meet the contract design specifications (AASHTO LRFD) before the product would be considered as acceptable to the government on this project.

Additional Note: The specifications on the material properties, for the elastomeric bearing pads, are minimum requirements as follows:

• The minimum elastomer hardness of the supplied material will be 60 durometers, and

• The minimum elastomer shear modulus, G, of the supplied material will be 200 PSI