42240025 RFI questions RESPONSES rebid.docx

DMVA 42240025 RANGE ROAD REPAVING

FORT INDIANTOWN GAP

AUGUST 5, 2024

RFI-1 - Is FDR (Full Depth Reclamation) going to be allowed on this project?

In this application, 12” FDR w/Portland Cement for the full depth areas on the plans. This process would include a certified mix design to provide the desired subgrade strength prior to work taking place.

With all work following PennDOT pub 408 spec, the process would go as follows:

1. Mix Design Sample existing road/subbase and perform mix design to calculate amount of Portland cement needed to achieve 250-500psi strength. Mix designs typical take 4-6 weeks to complete, depending on lab schedules. This mix design will then be tested in the field during our operation to confirm we are meeting requirements and design parameters.

2. Pulverization Once construction is scheduled, we start by pulverizing the existing road surface with a road reclaimer. This is performed by dry mixing the existing asphalt roadway with the existing subbase to create a uniform blend of asphalt, stone and subsoil. This mixture is left in-place after mixing. After pulverizing, we will compact, grade and shape the pulverized material to achieve design subgrade elevation and cross slope.

3. Apply Strength Agent After the existing road has been pulverized and shaped, we will surface spread dry Portland cement on the pulverized work area. The application rate for Portland cement is measured by LBS/Square Yard which will be provided by the certified mix design.

4. Mixing Once the Portland cement is spread, we will mix the cement with the pulverized road base to create a uniform blend of asphalt, stone, subsoil and Portland cement by using the road reclaimer. This process also includes directly injecting water into the mix to achieve optimum moisture. Moisture content is also provided by the certified mix design.

5. Grading Compact and grade the reclaimed base material.

6. Curing After the reclaimed base has been compacted and graded to design subgrade elevation, there are 2 separate curing options to choose from. Option #1 is to water cure the base by spraying water on the treated area for 7-days. Option #2 is to spray E1 Prime Coat on the treated area immediately following the daily construction while the reclaimed base is at optimum moisture. The E1 seals in the moisture and allows the reclaimed base to cure.

7. Paving PennDOT Pub 408 states to let the reclaimed base cure for 7-day period before performing strength break tests, but if schedule is fast paced, there is also an option to perform an early 3-day strength break test to monitor mid-way curing strength. After break tests are complete, paving may occur right on top of the reclaimed base, no stone subbase needed.

Project shall have yielded strength break tests of 400-600psi to provide a suitable base for new roadway paving.

ANSWER: Full Depth Reclamation may be used in areas where the plan shows and specifies full depth replacement. Notification of the use of Full Depth Reclamation alternative shall be submitted with the bid. The notification shall include the following information:

a. Contractor certification from PennDOT to complete this type of work.

b. Examples of previous projects completed by contractor of this type of work.

c. How will the contractor maintain the existing profile and cross-sections?

d. All work must be completed per PennDOT 408.

A proposed work schedule for each area of full depth reclamation shall be prepared and submitted. The contractor will also be responsible for all traffic control devices and control (material and personnel) in accordance with PennDOT standards.

Any further clarification or explanation required, please let me know.

Respectfully, DOROTHY A. STERNER, P.E.

DMVA – Engineering and Architecture

DMVA 42240025 RANGE ROAD REPAVING

FORT INDIANTOWN GAP

NOTIFICATION TO USE FULL DEPTH RECLAMATION

The Contractor is proposing to use Full Depth Reclamation as an alternative to Full Depth Replacement per RFI-1 dated 05 Aug 2024.

Provide below or attach:

Contractor certification from PennDOT to complete this type of work.

Examples of previous projects completed by contractor of this type of work.

Signed_______________________________________ Date _________________________