RFI_Taxiway_Repair.docx

EXHIBIT F

PROPOSAL INQUIRY FORMAT

SOLICITATION W912K6-15-R-0011

NOTE: ALL PRE-PROPOSAL INQUIRIES SHALL BE SUBMITTED VIA EMAIL IN THIS FORMAT!!

EMAIL: 175WG.MSC@ang.af.mil

Date of RFI Answer: 27 Aug 15

14 Aug 15

2.7.4.7 Rapid Set Cement ; Direction is needed, with a specific scope of concrete prep, precautions, procedures, psi strengths, mix requirements, exact testing required, placement , finishing, cold weather requirments and curing to protect the Maryland Air National Guard and the contractor.

1). Want is the concrete’s psi strength that Maryland Air National Guard is trying to achieve and in how many days of curing does the concrete have to meet that psi strength ?

2). What temperatures do you want the concrete poured in.

3). What procedures is required if temperatures fall.( Cold weather or Winter pouring) Blanketing? Double Blanketing , Chemicals, Temp heat etc.

4). Will theses days be credited back if the weather is to cold to pour concrete.

1. Concrete shall be 650 psi at 90 days (Specified Flexural Strength R)

2. Paving in hot weather: Concrete must not exceed 90 degrees F.

2a. Follow Practices found in ACI 305R.

3. Paving in cold weather: When the ambient temperature is less than 50 degrees F ensure temperature of concrete is not less than 50 degrees F. Do not place concrete unless the ambient temperature is at least 35 degrees F and rising.

3a Mixture Proportion: An accelerating admixture may be used when ambient temperature is below 50 degrees. Provide covering and other means for maintaining the temperature above freezing for not less than 72 hours.

4. An appropriate credit will be applied if applicable.

21 Aug 15

Our office has recently migrated our email accounts. Please send all correspondence to :

usaf.md.175-wg.list.msc@mail.mil

Michael.a.dombkiewicz.mil@mail.mil

Frank.d.harris.mil@mail.mil

27 Aug 15

ADDENDUM TO S.O.W. PJMS 132017 Full Depth & Spall Repairs

Excavation The contractor after demolition of existing concrete slab and removal of existing sub-base, will perform an inspection of the existing soil with the COR (Contracting Officer Representative) to determine suitably of soil. This is to verify any unsuitable material before commencing construction of new slab.

RFI

1. It is noted the dowel plan indicates all 4 sides of the new slabs are to receive dowels.

A) Will having dowels on all 4 sides allow the slabs sufficient movement or was the intent to have dowels placed in a single direction?

B) If dowels on all 4 sides are indeed required, please identify the direction in which expansion and contraction movement is intended and clarify greased dowel ends for the new slabs.

2. The detail for dowel placement shows dowel ends to be secured in existing slabs while greased in new slabs; however, not all new slabs abut existing slabs.

3. In those cases, where new slabs abut other new slabs, please indicate on the drawing, which dowel ends are to be stationary; and, which are to be grease treated?

See attachment "Dowelled Slab Locations"

4. It has been our understanding that MDE Permitting is a typical requirement when disturbing over 5,000 SF, including replacement upgrades and even more so when the subgrade is being disturbed or replaced as it is within the respective RFP; however, at the walk thru the Gvt noted there will be NO MDE Permitting requirements for this project. Please confirm or advise.

This is confirmed.

5. In order to establish/provide the proper drainage as noted within the requirements, please provide a Topo with the Existing Elevations & the Proposed Elevations of the new slab/area.

S.O.W. PJMS 132017 Par 2.7.2.1. Contractor will perform a detailed survey of the existing slab elevations (each slab corner) within the project area and 50ft. beyond the perimeter of the project area…………….

6. The UFC for Replacement verses Repair.

High/Early Concrete noted for Airfield Repair was mentioned in the RFP; however, since the area in question is more typical of a replacement than a localized crack or partial depth repair, please confirm the UFC 3-270-04 with a standard Airfield concrete mix design of 650 flex, will be an acceptable application for the area instead of the High/Early Concrete.

Contractor will provide a high early strength concrete mix design to achieve a compressive strength of 5,220 psi at 7 days and 7,098 psi at 28 days. Slump 3 inches plus or minus 1 inch.

7. During the walkthrough it was noted the current concrete grove depth was too deep. Please provide the intended depth and placement of the required groves for the new concrete.

Concrete will not be grooved finished. Finish concrete shall match existing adjacent slab areas.

8. In continuation of our question, is there some flexibility in the use of the Rapid Set Cement if the concrete submitted meets the same compressive strength and cure time? If not, is it to be assumed that all other bidders will be supplying an on-site mixer as well?

Suggest High Early Strength Concrete Mix. (See Answer No. 6)