Prebid RFI Expand MRI (2).docx

528-709 Expand for MRI Pre-Bid RFIs 2

1. In regards to the Wall Protection for this project: The only named manufacturer in the finish legend is Inpro. One of their competitors, Construction Specialties (CS), has reached out and stated that they will not quote this project unless an addendum comes out accepting them as an approved manufacturer, written by the Architect/VA.

We have been asked to submit this information, requesting Construction Specialties Inc, be allowed (added) to quote this project with their equivalent products. CS has noted that they will only supply products in their own colors, but they do have a color pallet that allows the choice of very similar colors as those already specified.

VA Response: Provide color selection as per Finish Schedule.

2. Specification 23 09 23 Direct-Digital Control System For HVAC, Part 2.11, subparagraph I. Specifies an Oxygen Sensor with a sample pump and zirconium oxide sensor. Furthermore, Detail 1 on Drawing M-803 states “The emergency fan (Typ 2) is activated either automatically by the laser optical oxygen sensor or manually by a wall mounted switch in the MRI scanner room or the MRI control room.”

Since a suggested sensor is not specified can you please provide a basis of design sensor to use or is a PureAire model number 99060 acceptable to use?

VA Response: The PureAire 99060 model suggested appears to meet the criteria of the specification.

3. The room finish schedule on Drawing AS-602 indicates epoxy paint for the floor finish in the basement area as shown on the basement finish plan (AS-701).

The paint specification doesn’t describe the epoxy paint. Paragraph 3.9 (Interior Finishes) lists “Concrete Walls”, but no information on concrete floors.

VA Response: Provide a penetrating water repellent concrete sealer in lieu of epoxy paint for the basement area.

4. Drilled Caisson Section 31 63 26 (1.8) (G) (2) references pile load testing of ACPs. ACP is typically used as an abbreviation for Auger Cast Piles constructed with continuous flight hollow-stem augers where grout is pumped through the center of the augers during drill operation without the use of temporary casing. The rest of the project documents describe traditional, temporarily cased caissons. Typically, traditional caissons are not load tested like ACPs, driven piles, micropiles or tiebacks.

Is Section 31 63 26 (1.8) (G) (2) applicable to this project? If it is, please provide both compression loads and lateral loads for each size of caisson, detail on which caissons need each ASTM D1142 and ASTM D3966 tests, and if any of the caissons are sacrificial.

VA Response: The specification reference related to the pile load testing is a part of the VA’s master caisson specification and therefore we left it in. Miller Remick takes no exceptions to eliminating load testing of the caissons. However, the contractor is required to test and inspect the drilled shaft by the testing and inspection geotechnical engineer as required per the drawings and specifications including, but not limited to, caisson subgrade bearing capacity, sides and bottom of caisson, concrete tests, etc.

5. Drilled Caisson Section 31 63 26 (1.9) (F) references Grout Mix Designer. Typically grout refers to a fine or neat cementitious product that is pumped in an ACP or tremie application. This project will use ready-mix concrete as detailed in Section 31 63 26 (2.1) (H).

Does Section 31 36 26 (1.9) (F) apply to this project?

VA Response: “Grout Mix” refers to the caisson concrete. “Concrete mixes” is also noted in this specification section. This specification section does apply to the caisson concrete.

6. Drilled Caisson Section 31 63 26 (3.2) (D) requires probe holes drilled in the bottom of each caisson that are installed into rock. All caissons on this project are to be installed into rock.

Does every caisson need to be probed?

VA Response: Yes.

7. Do the probe holes require grouting after installation?

VA Response: Yes, after inspection is completed and approved (see response below).

8. Can the probe holes be drilled before the caissons are installed?

VA Response: Yes, holes shall be drilled before caissons are installed. Holes need to be inspected to determine that material is capable of supporting bearing capacity (refer to Testing/Inspection specification).