Attachment_G-2022-02-08_Coring_Report.pdf

TIERRA

7351 Temple Terrace Highway Tampa, FL 33637 Phone (813) 989-1354 Fax (813) 989-1355

Florida Certification No. 6486

February 8, 2022

Mr. Charles Leazott Citrus County Engineering 3600 W. Sovereign Path, Ste 241 Lecanto, FL 34461

Re: Milling and Resurfacing Recommendations East Gospel Island Road from East Vine Street to East Gulf to Lake Highway Citrus County, Florida Tierra Project No. 6111-22-001.003

Dear Mr. Leazott, Tierra, Inc. has completed a limited pavement evaluation to develop milling and resurfacing recommendations for the subject roadway.

General Summary

East Gospel Island Road is a two-lane roadway in Citrus County, Florida. The limits of the subject area of study are from East Vine Street to East Gulf to Lake Highway which is approximately 4.1 miles. The roadway condition along the subject alignment is mostly in fair to poor condition with Class II and III moderate to severe block and longitudinal cracking.

Pavement Section Exploration

A total of 25 cores were extracted along the alignment in both the eastbound and westbound lanes.

The cross slope measurement and average rut depth were measure at each core location at the time of coring. From the cores extracted from the westbound lane, the average asphalt thickness was measured to be 3.3 inches with an average cross slope of 2.5% and average rut depth of less than ¼ inch. From the cores extracted from eastbound lane, the average asphalt thickness was measured to be 4.8 inches with an average cross slope of 2.4% and average rut depth of less than ¼ inch. A layer of limerock base material with an average thickness of 5.8 inches was encountered beneath the asphalt at the core locations.

The results are summarized in the following table:

Milling and Resurfacing Recommendations

Citrus County, Florida Tierra Project No. 6111-22-001.003

CLIENT: DATE:

PROJECT: JOB NO:

Core No. Asphalt Type Asphalt

Thickness (in.)

Base Thinkness

(in.)

Base Type Cross Slope

Rut Depth

(in) Lane Notes

C-1 S-3 4 8.0 Limerock 6.1 <1/4 WB

C-2 S-3 5 6.0 Limerock 3.1 <1/4 WB

C-3 S-3 4 1/2 5.0 Limerock 2.0 <1/4 WB

C-4 S-3 3 6.0 Limerock 1.6 <1/4 WB

C-5 S-3 4 1/2 5.0 Limerock 3.1 <1/4 WB

C-6 S-3 5 5.5 Limerock 2.5 <1/4 WB

C-7 S-3 4 6.0 Limerock 3.5 <1/4 WB

C-8 S-3 3 6.0 Limerock 1.1 <1/4 WB

C-9 S-3 4 5.0 Limerock 1.1 <1/4 WB

C-10 S-3 4 9.0 Limerock 2.5 <1/4 WB

C-11 S-3 3 1/2 5.0 Limerock 1.5 <1/4 WB

C-12 S-3 3 6.0 Limerock 1.7 <1/4 WB

C-13 S-3 2 1/2 5.5 Limerock 2.1 <1/4 WB

C-14 S-3 4 1/2 5.5 Limerock 5.4 <1/4 EB

C-15 S-3 5 3/4 5.0 Limerock 1.0 <1/4 EB

C-16 S-3 4 1/2 6.0 Limerock 0.2 <1/4 EB

C-17 S-3 4 3/4 6.0 Limerock 4.1 <1/4 EB

C-18 S-3 5 1/2 4.0 Limerock 1.8 <1/4 EB

C-19 S-3 4 1/2 5.5 Limerock 3.7 <1/4 EB

C-20 S-3 4 5.5 Limerock 1.6 <1/4 EB

C-21 S-3 5 8.0 Limerock 2.1 <1/4 EB

C-22 S-3 4 7.5 Limerock 1.4 <1/4 EB

C-23 S-3 4 1/2 5.0 Limerock 1.2 <1/4 EB

C-24 S-3 5 4.5 Limerock 1.6 <1/4 EB

C-25 S-3 7 5.0 Limerock 5.1 <1/4 EB

Lat 28.856513⁰, Long -82.273169⁰

Lat 28.861001⁰, Long -82.288973⁰

Lat 28.855132⁰, Long -82.311435⁰

Lat 28.860470⁰, Long -82.290599⁰

Lat 28.851391⁰, Long -82.273692⁰

Lat 28.850017⁰, Long -82.274982⁰

Citrus County, Florida Board of County Commissioners

Lat 28.859971⁰, Long -82.301436⁰

Lat 28.859934⁰, Long -82.302258⁰

Lat 28.858819⁰, Long -82.309438⁰

Lat 28.854446⁰, Long -82.311659⁰

Lat 28.859887⁰, Long -82.296010⁰

Lat 28.850046⁰, Long -82.274999⁰

East Gospel Island Road from East Vine Street to East Gulf to Lake Highway

Lat 28.862484⁰, Long -82.282592⁰

Lat 28.860896⁰, Long -82.276701⁰

Lat 28.859697⁰, Long -82.294604⁰

Lat 28.859465⁰, Long -82.308537⁰

Lat 28.856954⁰, Long -82.273235⁰

Lat 28.860559⁰, Long -82.274911⁰

Lat 28.862828⁰, Long -82.284609⁰

Lat 28.846776⁰, Long -82.320031⁰

Lat 28.847192⁰, Long -82.319164⁰

Lat 28.849750⁰, Long -82.314456⁰

2/3/2022

Lat 28.849256⁰, Long -82.314876⁰

Location

Lat 28.861838⁰, Long -82.279677⁰

6111-22-001-003

TABLE 1 : THICKNESS OF ASPHALT & BASE

LABORATORY TEST DATA

Lat 28.851048⁰, Long -82.273561⁰

Citrus County, Florida

Pictures of Extracted Cores:

Core 1(Lat 28.850046⁰, Long -82.274999⁰) Core 2 (Lat 28.851048⁰, Long -82.273561⁰)

Core 3 (Lat 28.856954⁰, Long -82.273235⁰) Core 4 (Lat 28.860559⁰, Long -82.274911⁰)

Citrus County, Florida

Core 5 (Lat 28.861838⁰, Long -82.279677⁰) Core 6(Lat 28.862828⁰, Long -82.284609⁰)

Core 7 (Lat 28.860470⁰, Long -82.290599⁰) Core 8 (Lat 28.859887⁰, Long -82.296010⁰)

Citrus County, Florida

Core 9 (Lat 28.859934⁰, Long -82.302258⁰) Core 10 (Lat 28.858819⁰, Long -82.309438⁰)

Core 11 (Lat 28.854446⁰, Long -82.311659⁰) Core 12 (Lat 28.849256⁰, Long -82.314876⁰)

Citrus County, Florida

Core 13 (Lat 28.846776⁰, Long -82.320031⁰) Core 14 (Lat 28.847192⁰, Long -82.319164⁰)

Core 15 (Lat 28.849750⁰, Long -82.314456⁰) Core 16 (Lat 28.855132⁰, Long -82.311435⁰)

Citrus County, Florida

Core 17 (Lat 28.859465⁰, Long -82.308537⁰) Core 18 (Lat 28.859971⁰, Long -82.301436⁰)

Core 19 (Lat 28.859697⁰, Long -82.294604⁰) Core 20 (Lat 28.861001⁰, Long -82.288973⁰)

Citrus County, Florida

Core 21 (Lat 28.862484⁰, Long -82.282592⁰) Core 22 (Lat 28.860896⁰, Long -82.276701⁰)

Core 23 (Lat 28.856513⁰, Long -82.273169⁰) Core 24 (Lat 28.851391⁰, Long -82.273692⁰)

Citrus County, Florida

Core 25 (Lat 28.850017⁰, Long -82.274982⁰)

Resurfacing Recommendations

Option 1: Mill and resurface to a depth of 4 inches. This milling depth should remove most of the cracked asphalt. Upon completion of the milling and prior to resurfacing it is recommended to proofroll any exposed base material. It is recommended to resurface with 2” of SP 12.5 asphalt topped with 2” of FC 12.5 containing a 76-22 binder to help resist future pavement rutting. The designer should include provisions for encountering the base course, including but not limited to contamination of the millings, and exposing the base to rain and weather elements.

Option 2: Mill and resurface to a depth of 2¾ inches. It is recommended to place a ¾ inch ARMI (Asphalt Rubber Membrane Interlayer) layer and resurface with a 2 inch layer of FC 12.5 containing a 76-22 binder to help resist future pavement rutting. The ARMI layer should minimize the reflective cracking.

General Discussion

The roadway is mostly in fair to poor condition with Class II and III moderate to severe block and longitudinal cracking. At the core locations the cracks extend all the way to the base. The intent of the deep milling and resurfacing is to remove most of the Type S structural asphalt and replace the fatigued asphalt and provide a stronger pavement section. The asphalt thicknesses at the core locations indicate that the base will likely be exposed during deeper milling and precautions to protect the base from weather is important. The designer should include provisions to make sure that the contractor does not leave any base course exposed at the end of the day as the potential for a rain event could saturate the base. Milling 2 inches (shallow) and installing the ARMI/crack relief layer is typically quicker and more cost effective than deep milling. It’s important to make sure there is at least 2 inches of asphalt over the ARMI layer to avoid encountering it during future milling operations.

Citrus County, Florida

Tierra appreciates this opportunity to offer our services. Should you have any questions or request any additional information, please do not hesitate to contact our office.

Respectfully Submitted, TIERRA, INC.

James Gibbs Jeffrey Begovich, P.E.

Construction Services Manager Principal Engineer Florida License No. 51869