160STABILIZING

160-1 Description.

Stabilize designated portions of the roadbed to provide a firm and unyielding subgrade, having the required bearing value specified in the Plans.

160-2 Materials.

160-2.1 Commercial Material: Meet the requirements of Section 914-2.1.

160-2.2 Local Material: Submit test results to the Engineer at least 14 days prior to the

stabilization operation.

160-2.2 1 Local Stabilizing Material: Sample and test material from each source

and meet the requirements of Section 914. The Engineer will verify the Quality Control (QC) test results meet the requirements of Section 914. If the QC and Verification results do not compare, the Engineer will take one additional sample of material from the s ource in question and the State Materials Office (SMO) or an AASHTO accredited laboratory designated by the SMO will perform Resolution testing. If the Resolution test results satisfy the required criteria, material from that source will be verified and ac cepted. If the Resolution test results do not meet the required criteria, reject the material.

160-2.2 2 Reclaimed Asphalt Pavement (RAP) : Obtain the Engineer’s approval

in writing for the option to use 100% RAP material . Material must be milled and stoc kpiled without blending or contaminating with any other material .

160-2.2 3 Reclaimed Asphalt Pavement (RAP ) Blended Material : RAP

blended material is defined as material meeting the requirements of 914 -1 and 914 -2.2 except for the limits for organic content. If the RAP blended material meets the requirements of 914 -1 and 914-2, then the blended material will be classified as local stabilizing material . Provide test results to the Engineer and obtain their approval in writing before using RAP blended material. The Engineer will verify that the QC test results meet the acceptance criteria, otherwise the Engineer will perform Resolut ion testing procedures specified in 160 -2.2.1.

160-2.3 Existing Base: Obtain the Engineer’s approval in writing before using existing

base. When the material from an existing base is used as all, or a portion, of the stabilizing additives, no further test ing is required unless directed by the Engineer.

160-2.4 Granular Subbase : The Engineer may allow, at no additional cost to the

Department, the substitution of 6 inches of granular subbase meeting the requirements of 290 -2 and 290-3, only when 12 inches of Type B stabilization requiring a Limerock Bearing Ratio (LBR) value of 40 is specified in accordance with Standard Plans, Index 120-001.

160-3 Construction Methods.

160-3.1 General: Prior to the beginning of stabilizing operations, construct the area to be

stabilized to an elevation such that, upon completion of stabilizing operations, the completed stabilized subgrade will conform to the lines and grades shown in the Plans. Prior to spreading any additive stabilizing material, bring the surface of the r oadbed to a plane approximately parallel to the plane of the finished graded surface shown in the Plans. Construct mainline pavement lanes, turn lanes, ramps, parking lots, concrete box culverts, retaining wall systems, shoulder -only areas, sidewalk, and shared use path areas meeting the requirements of 120 -8.1, except replace “embankment” with “subgrade”. FY 2023-24 Return to Table of Contents Isolated mixing operations will be considered as separate LOTs. Curb pads and shoulders compacted separately shall be considered separate LOTs. Isolated compaction operations will be considered as separate LOTs. For multiple phase construction, a LOT shall not extend beyond the limits of the phase .

160-3.2 Application and Acceptance of Stabilizing Material: After complet ing the

roadbed grading operations, determine the type and quantity (if any) of stabilizing material necessary for compliance with the bearing value requirements. Before using any Fossil Fuel Combustion Products (FFCPs), submit documentation, at the precon struction meeting or no later than 30 days prior to delivery of FFCP’s to the project, signed and sealed by the Specialty Engineer that these materials meet the requirements of 403.7047 F.S. Notify the Engineer of the approximate quantity to be added befor e spreading. When additive stabilizing materials are required, spread the material uniformly over the area to be stabilized. The Engineer may perform Independent Verification (IV) sampling and testing if variability in the stabilizing material is observe d during inspection after spreading on the roadway. If the IV test results do not meet the requirements of Section 914, then remove and replace the failing LOTs with acceptable material. The Engineer reserves the right to reject stabilizing material that c ontains excessive deleterious substances.

160-3.3 Mixing: Perform mixing using rotary tillers, a plant or other equipment meeting

the approval of the Engineer. The subgrade may be mixed in one course if the equipment and method of construction provides th e uniformity, particle size limitation, compaction and other desired results of 160 -4. Thoroughly mix the area to be stabilized throughout the entire depth and width of the stabilizing limits. Perform the mixing operations, as specified, (either in place or in a plant) regardless of whether the existing soil, or any select soils placed within the limits of the stabilized sections, have the required bearing value without the addition of stabilizing materials.

160-3.4 Mixed Material Requirement s: At the completion of the mixing, ensure the

gradation of the material within the limits of the area being stabilized is such that 97% will pass a 3-1/2 inch sieve. Break down or remove from the stabilized area materials, including clay lumps or lumps made of clay -size particles (any particle size 2 microns or less), not meeting the gradation requirements. After mixing, remove any existing lumps of clay or clay -sized particles greater than one inch that do not meet the requirements of 160 -3.2 or this Section from the stabilized area. The final product must meet the acceptance requirements of 160 -4.

160-3.4 1 Classification and Bearing Value: Meet the soil utilization and

bearing value requirements for the subgrade in accordance with 160 -4.

160-3.4 2 Compaction: After completing the mixing operations and satisfying

the requirements for bearing value, uniformity, and particle size, compact the materials at a moisture content permitting the specified compaction in 160 -4.2.3. If the moisture content of the material is improper for attaining the specified density, either add water or allow the material to dry until reaching the proper moisture content for the specified compaction.

160-3.4 3 Finish Grading: Shape the completed stabilized subgrade to conform

with the fin ished graded surface shown in the Plans. Check the subgrade using elevation stakes or other means approved by the Engineer.

160-3.4 4 Condition of Completed Subgrade: After completing the stabilizing

and compacting operations, ensure that the subgrade is firm and substantially unyielding to the extent that it will support construction equipment and will have the bearing value required by the Plans. FY 2023-24 Return to Table of Contents Remove all soft and yielding material, and any other portions of the subgrade which will not compact read ily, and replace it with suitable material so that the whole subgrade is brought to line and grade, with proper allowance for subsequent compaction.

160-3.4 5 Maintenance of Completed Subgrade: After completing the subgrade

as specified above, maintain i t free from ruts, depressions, and any damage resulting from the hauling or handling of materials, equipment, tools, etc. The Contractor is responsible for maintaining the required density until the subsequent base or pavement is in place including any repairs, replacement, etc., of curb and gutter, sidewalk, etc., which might become necessary in order to recompact the subgrade in the event of underwash or other damage occurring to the previously compacted subgrade. Perform any such recompaction at no expen se to the Department. Construct and maintain ditches and drains along the completed subgrade section.

160-4 Acceptance Program for Mixed Materials .

160-4.1 General Requirements:

160-4.1 1 Initial Equipment Comparison: Meet the requirements of 120 -10.1.1.

160-4.1 2 Initial Production LOT: Meet the requirements of 120 -10.1.2.

160-4.1 3 Density over 105%: Meet the requirements of 120 -10.1.3.

160-4.1 4 Quality Control Tests:

160-4.1 4.1 Modified Proctor Maximum De nsity Determination:

Collect enough material to split and create three separate samples. Determine test locations, including stations and offsets, using the Random Number generator approved by the Department. Retain the Verification and Resolution samples for the Department until the Engineer accepts the LOTs represented by the samples. Determine modified Proctor maximum density and optimum moisture content by sampling and testing the material in accordance FM 1-T 180.

160-4.1 4.2 Density Testing Require ments: Meet the requirements of

120-10.1 4.2.

160-4.1 4.3 Bearing Value Requirements: Test the stabilized subgrade

sample collected in 160-4.1.4.1 to determine the LBR in accordance with FM 5-515. Within the entire limits of the width and depth of the a reas to be stabilized, obtain the required minimum bearing value at the frequency in 160 -4.4.1. For any area where the bearing value obtained is deficient from the value indicated in the Plans, in excess of the tolerances established herein, spread and mix additional stabilizing material in accordance with 160 -3.3. Perform this reprocessing for the full width of the roadway being stabilized and longitudinally for a distance of 50 feet beyond the limits of the area in which the bearing value is deficient. Determine the quantity of additional stabilizing material to be used in reprocessing.

160-4.1 4.3.1 Under-tolerances in Bearing Value

Requirements: The under -tolerances are allowed for the following specified Bearing Values: Table 160-1 Specified Bearing Value Under-tolerance LBR 40 5.0 LBR 35 4.0 LBR 30 (and under) 2.5 FY 2023-24 Return to Table of Contents

160-4.1 4.3.2 Unsoaked LBR Requirements: If unsoaked LBR is

desired, submit request for approval to the Engineer. Upon approval by the Engineer to consider the use of unsoaked LBR, randomly sample and test from three locations in the initial LOT for both soaked and unsoaked LBR in accordance with FM 5-515. Ensure all of the tests achieves the LBR value shown in the table below. Continue testing unsoaked LBR at the frequency shown in 160-4.4.1. Discontinue unsoaked LBR testing if any unsatisfactory QC LBR test result is obtained or resolution deter mines an unsatisfactory LBR. The following unsoaked bearing value requirement is based on tests performed on samples obtained after completing mixing operations: Table 160-2 Specified Bearing Value Unsoaked Bearing Value Required Under-tolerance LBR 40 LBR 43 0.0

160-4.1 4.4 Soil Classification and Organic Content Testing: Perform

soil classification tests on the sample collected in 160 -4.1.4.1, in accordance with AASHTO T88, AASHTO T89, AASHTO T90, and FM 1-T 267. The Engineer may waive the soil classification and organic content testing requirements for existing base or granular subbase materials. Classify soils in accordance with AASHTO M145 to determine compliance with soil utilization requirements as specified in St andard Plans, Index 120-001. If the stabilizing material used is 100% RAP or RAP blended material, then replace FM 1-T 267 with FM 5-563 (excluding gradation analysis ). The following testing requirements must be met. Table 160-3 Test Method Criteria AASHTO M145 Soil Symbol = S FM 1-T 267 Average of 3 Organic Content ≤ 2.5% Individual Organic Content Result ≤ 4.0% AASHTO T89 Liquid Limit ≤ 30 AASHTO T90 Plastic Index ≤ 8 FM 5-563* Asphalt Content ≤ 4.0% * Replace FM 1 -T 267 with FM 5 -563 (excluding gradation analysis) for 100% RAP or RAP blended material

160-4.1 5 Department Verification: Meet the requirements of 120 -10.1.5 except

the Engineer will conduct the Verification tests in order to accept all materials and work associated with 160 -4.1.4.

160-4.1 6 Reduced Testing Frequency: Meet the requirements of 120 -10.1.6.

160-4.1 7 Paymen t for Resolution Tests: Meet the requirements of 120 -10.1.7.

160-4.2 Mixing Depth Requirements: Report depth requirements in the Earthwork

Records System (ERS) section of the Department’s database measured to the nearest 0.25 inch. The difference between the individual measured depth thickness on the roadway and the plan target thickness must not exceed 2 inches. The difference between the LOT average (average of FY 2023-24 Return to Table of Contents the three individual measured depth thickness) and the plan target thickness must not exceed 1 inch. No undertolerance of mixing depth is allowed. As an exception to the above mixing requirements, where the subgrade is of rock, the Engineer may waive the mixing operations (and the work of stabilizing), and the Department will not pay for stabiliz ation for such sections of the roadway. Meet the required Plan mixing -depths by measuring from the proposed final grade line. Determine test locations, including stations and offsets, using the Random Number generator approved by the Department. Notify t he Engineer a minimum of 24 hours before checking mixing depths. Record results on Department approved forms .

160-4.3 Density Acceptance Criteria :

160-4.3 1 General: Within the entire limits of the width and depth of the areas to

be stabilized, other th an as provided in 160 -4.3.2, obtain a minimum density at any location of 98% of the Modified Proctor maximum density as determined by FM 1-T 180.

160-4.3 2 Exceptions to Density Requirements: The Contractor need not obtain

the minimum density specified in 160 -4.3.1 in the upper 6 inches of areas to be grassed under the same Contract. Compact these areas to a reasonably firm condition as directed by the Engineer.

160-4.4 Additional Requirement s:

160-4.4 1 Frequency : Conduct QC sampling and testing at a minimum frequency

listed in the table below. The Engineer will perform Verification sampling and tests at a minimum frequency listed in the table below. Table 160-4 Test Name Quality Control Verification Verification for Shoulder-Only, Shared Use Path and Sidewalk Construction Modified Proctor Maximum Density One per two consecutive LOTs One per eight consecutive LOTs One per four LOTs LBR Gradation, LL/PI, and Soil Classification Organic Content Asphalt Content* Density One per LOT One per four LOTs One per two LOTs Stabilizing Mixing Depth Three per 500 feet Witness QC Witness QC *Replace organic content with asphalt content for 100% RAP or RAP blended material only.

160-4.5 Verification Comparison Criteria and Resolution Procedures:

160-4.5 1 Bearing Value : The Engineer will collect a sample at a location other

than the location where the sample was collected in 160-4.1.4.1, and test the stabilized subgrade for determination of the LBR in accordance with FM 5-515. The Engineer will select test locations, including stations and offsets, using a Random Number generator, based on the LOTs under consideration. FY 2023-24 Return to Table of Contents

160-4.5 1.1 Unsoaked LBR : The Engineer will sample and test the initial

LOT for one soaked and one unsoaked LBR if consideration of the unsoaked LBR has been approved.

160-4.5 1.2 Resolution Procedure: If the Department’s Verification test

meets the require ments of 160 -4.1.4.3, the Engineer will accept the corresponding LOTs. Otherwise, the Engineer will collect an additional sample in the same LOT the Verification sample was obtained. SMO or an AASHTO accredited laboratory designated by SMO will perform Res olution testing on the additional sample. The material will be sampled and tested in accordance with FM 5-515. If the resolution testing results meet the requirements of 160 - 4.1.4.3, then the Engineer will accept the LOTs in question. Otherwise reproce ss the corresponding LOTs in accordance with 160 -3 and retest in accordance with 160 -4.1.4.3.

160-4.5 2 Modified Proctor Maximum Density Determination: The Engineer

will randomly select one of the retained split samples referenced in 160-4.1.4.1. The Eng ineer will compare the Verification test results to the corresponding Quality Control (QC) test results. If the test result is within 4.5 lb/ft3 of the QC test result, the LOTs will be verified. Otherwise, the Engineer will collect the Resolution split sam ple corresponding to the Verification sample tested. The State Materials Office or an AASHTO accredited laboratory designated by the State Materials Office will perform Resolution testing. The material will be sampled and tested in accordance with FM 1-T 180. The Engineer will compare the Resolution Test (RT) results with the QC test results. If the RT result is within 4.5 lb/ft3 of the corresponding QC test result, the Engineer will use the QC test results for material acceptance purposes for each corre sponding pair of LOTs. If the RT result is not within 4.5 lb/ft3 of the corresponding QC test, the Engineer will collect and test the remaining Verification split samples for the LOTs in question. Verification test results will be used for material accepta nce purposes for the remaining LOTs in question.

160-4.5 3 Density Testing: Meet the requirement of 120 -10.4.2

160-4.5 4 Soil Classification: Meet the requirements of 120 -10.4.3 with the

exception that the limits will be in accordance with 160 -4.1.4.4.

160-4.5 5 Organic Content: Meet the requirements of 120 -10.4.4 with the

exception that the limits will be in accordance with 160 -4.1.4.4.

160-4.5 6 Asphalt Content: If the material used to stabilize is 100% RAP or

RAP blended material, meet the requirement of 120 -10.4.4, except replace FM 1-T 267 with FM 5-563 (exclude gradation analysis) and meet the limits of 160 -4.1.4.4.

160-4.5 7 Mixing Depth: The Engineer will witness the Contractor’s mixing

depth checks to ensure compliance with 160 -4.2. The Engineer will select test locations, including stations and offsets, using a Random Number generator. The Department will witness the mixing depth checks.

160-4.6 Disposition of Defective Materials: Meet the requirements of 120 -10.5.

160-5 Method of Measurement.

The quantity to be paid for will be the plan quantity, in square yards, comple ted and accepted.

160-6 Basis of Payment.

Price and payment will constitute full compensation for all work and materials specified in this Section, including furnishing, spreading and mixing of all stabilizing material required and any reprocessing of sta bilization areas necessary to attain the specified bearing value. The Department will make full payment for any areas where the existing subgrade materials meet the design bearing value requirements without the addition of stabilizing additives, as well as areas where the Contractor may elect to place select high -bearing materials from other sources within the limits of the stabilizing. If the item of borrow excavation is included in the Contract, any stabilizing materials obtained from designated borrow a reas will be included in the pay quantity for borrow excavation. Payment will be made under: Item No. 160 - 4- Stabilization - per square yard. FY 2023-24 Return to Table of Contents SECTION 175 CRACKING AND RESEATING EXISTING CONCRETE PAVEMENT

175-1 Description.

Perform controlled cracking of concrete pavement and reseating of the cracked slabs, by rolling, tamping, etc., on the underlying subgrade to provide a firm base for asphalt concrete surfacing.

175-2 Equipment.

175-2.1 For Cracking: Provide pneumatic or gravity -type breakers, or other specifically

approved equipment that ensures controlled cracking to the size and extent of uniformity, etc., specified. C ontrol the fall of gravity -type breakers by leads so that the fall will be straight and vertical. Use hammers for both pneumatic and gravity -type breakers of a type that will crack the concrete cleanly and not punch or unnecessarily shatter the concrete.

175-2.2 For Reseating Provide vibratory compacting equipment or traffic rollers. Use

traffic rollers that weigh at least 15 tons.

175-3 Construction Requirements.

175-3.1 Protection of New Construction and Adjacent Structures: Perform cracking

and reseati ng work prior to beginning all new construction which this work might endanger or disturb. Perform cracking and reseating in a manner that will not damage any existing structures which are to remain, and repair any damage to such structures that this work causes by this work at no expense to the Department.

175-3.2 Cracking and Seating: For the cracked slabs, make clean fractures, as near

vertical as practicable. Do not punch the pieces into the subgrade, but firmly seat them thereon, to as uniform a conto ur as is practicable.

175-3.3 Special Requirements for Asphalt -Surfaced Pavement: Where the existing

concrete pavement is covered with an asphalt surface, remove the asphalt surfacing (after the cracking operation) on test areas approximately 10 by 10 feet, at locations selected by the Engineer, in order to determine if the required results are being obtained in the cracking operations. Prepare at least one such test area for each day's operation, and prepare additional areas if deemed necessary by the Eng ineer.

175-3.4 Dimensions of Slabs: Ensure that the cracked slabs have no dimension greater

than 3 feet. In the event that the required results in the cracking are not being obtained, adjust the spacing of blows or the height of drop of the blows as neces sary to obtain the required results with the equipment being used.

175-4 Method of Measurement.

The quantity to be paid for will be the plan quantity, in square yards, of existing concrete pavement acceptably cracked and reseated on the subgrade.

175-5 Basis of Payment.

Price and payment will be full compensation for performing and completing all work specified in this Section. Payment will be made under: Item No. 175 - 1- Reseating Concrete Pavement - per square yard. FY 2023-24 Return to Table of Contents