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HomeMy WebLinkAboutFIRST AMENDMENT TO CONTRACT BETWEEN AUGUSTA, GEORGIA AND MCCARTHY IMPROVEMENT COMPANY AT AUGUSTA REGIONAL AIRPORT FIRST AMENDMENT TO CONTRACT AIRPORT Augusta Regional Airport Date January 29,2019 LOCATION Augusta, GA AIP No. 3-13-0011-042-2018 CONTRACTOR McCarthy Improvement Company You are requested to perform the following described work upon receipt of an approved copy of this document or as directed by the engineer. Item Bid No. Alternate Description Unit Unit Price Quantity Amount X-100.1 Base Mobilization, Cleanup, and LS -$15,000.00 1 -$15,000.00 Demobilization P-304.3 Base Portland Cement for Cement CWT $7.00 -2,731 -$19,117.00 Treated Base(Base Bid) P-304.3 Base Portland Cement for Cement CWT $7.00 -532 Treated Base(Bid Alt 1) -$3,724.00 X-100.1 2 Mobilization, Cleanup, and LS $35,000.00 -1 -$35,000 Demobilization X-100.2 2 Airfield Safety and Traffic LS $5,000.00 -1 Control -$5,000.00 Asphaltic Concrete Pavement P-101.1 2 Removal,Full Depth,Remove SY $18.00 -930 -$16,740.00 Off-Site X-150.2 2 Remove Storm Sewer Pipe, 18- LF $25.00 -413 -$10,325.00 Inch X-150.5 2 Remove Storm Sewer Catch EA $875.00 -2 Basin Structure -$1,750.00 X-150.8 2 Remove Pavement Markings SF $1.60 -3517 -$5,627.20 P-152.2 2 Subgrade Preparation SY $3.30 -930 -$3,069.00 P-154.1 2 Uncrushed Aggregate Base CY $92.00 -211 -$19,412.00 Course(6"Depth) P-401.1 2 Asphalt Concrete Surface TON $180.00 -864 Course -$155,520.00 P-620.1 2 Permanent Pavement Marking SF $2.00 -3850 -$7,700.00 D-751.4 2 Connect Storm Sewer Pipe to EA $5,200.00 -1 Existing Storm Line -$5,200.00 T-901.1 2 Seeding AC $1,750.00 -1 -$1,750.00 T 905.1 2 Topsoiling(Obtain on Site or CY $42.00 -28 Removed from Stockpile) -$1,176.00 This Change Order Total -$306,110.20 Previous Change Order(s)Total $0.00 Original Contract Total $12,942,155.50 Revised Contract Total $12,636,045.30 The time provided for completion in the contract is(unchanged)(decreased)(increased)by 40 calendar days. This document shall become the First Amendment to the contract and all provisions of the contract will apply. 4 Recommended by: 1,„,,„,9 Christopher J.Birkmeyer,PE,Engineer(Mead&Hunt,Inc.) Date Approved by: Q) �a __ illa Hilton, hairwoman (Augusta Aviation Commission) Date Accepted by: 1"j I LCL 6.-H rl U ._ .14 //2- Q/26)/q Contractor(McCarthy Improvement Co ,p i , Date Page 2 of 4 AIP NO. 3-13-0011-042-2018 FIRST AMENDMENT TO THE CONTRACT AIRPORT Augusta Regional Airport(AGS) LOCATION Augusta, GA JUSTIFICATION FOR CHANGE 1. Brief description of the proposed contract Amendment and location(s). X-100.1 Base Bid: Reduced time to complete the project based on the revised method will reduce the management cost of the contractor due to the 40 days of time that will be saved with the proposed method. P-304.3 Base Bid and Bid Alternate 1: Cost of Portland Cement for Cement Treated base has been rolled into the overall unit cost for the Portland Cement Pavement throughout the project. Bid Alternate 2: All work associated with Bid Alternate 2 will be completed with the inclusion of Bid Alternate 1 in the project. These quantities are redundant and can be removed from the project. 2. Reason(s)for the change(s) (Continue on reverse if necessary) The project will construct portions of the commercial service and general aviation apron. The contractor has raised concerns of weather risks associated with the Project starting in January and the up to 30"deep excavations confined by surrounding pavements. Our experience in managing construction projects at the Airport during the past five years is that from the middle of December until the first of March the Airport experiences cycles of rain followed by cooler temperatures when the sun comes out. These conditions are not conducive to drying out subgrades and base materials. This weather pattern caused significant delays on the ARFF pavement project and the TW A project that was recently completed. To mitigate these concerns,the Contractor has requested that we consider allowing the cement treated base course to be constructed with a mix in place method instead of the central mixing plant method as defined in FAA Spec Sec P-304. This will allow for the Contractor to spread all of the base material at one time and then to blend it and finish it within a couple of days instead of over the course of a month that it would take to construct in lanes as required by a central mixing plant operation. The Contractor has provided letters of reference for a similar change in methods on a concrete apron project and a letter from the American Concrete Pavement Association supporting the proposed method.No changes to pavement structure or section has been proposed. Mead&Hunt has evaluated the proposal with our geotechnical engineer on the Project and has reviewed documentation from the Portland Cement Association,Department of Defense Unified Facilities Criteria,North Carolina Department of Transportation, and Tennessee Department of Transportation. All of these entities allow for the use of mixed in place cement treated aggregate bases. We have also discussed the Project with the American Concrete Pavement Association. Based on this research we have drafted changes to the P-304 specification that would allow for the use of mixed in place cement-treated base provided that additional testing be performed to monitor the uniformity of the mixing along the edges of construction. Mead&Hunt has evaluated the request provided by McCarthy Improvement Company and find that the proposed change to mixing and placement methods of the cement-treated base are beneficial to this project. The proposed revisions to the P-304 specifications require additional testing to be performed to provide adequate quality assurance of the in-place P- 304 material. The changes have been tracked on the attached word document for easy reference. No pavement sections will be modified for the Project with this proposed change. 3. The Sponsor's share of this cost is available from: NA 4. If this is a supplemental agreement involving more than$2,000, is the cost estimate based on the latest wage rate decision? Yes ® No [ Not Applicable n 5. Has consent of surety been obtained? Yes n Not Necessary El Page 3 of 4 6. Will this change affect the insurance coverage? Yes n No 7. If yes,will the policies be extended? Yes ❑ No ❑ Not Applicable El 8. Has this Change Order been discussed with FAA officials? Yes ® No❑ When: 1/17/2019 With Whom: Mr.Nick Goodly Comment(s): The Contract shall be amended to delete Item Item P-304 Cement-treated Base Course and replace it with the attached revised Item P-304 Cement-treated Base Course specification dated November 14, 2018. Page 4 of 4 FAA 150/5370-1 OG (7/21/2014)—MODIFIED ITEM P-304 CEMENT-TREATED BASE COURSE DESCRIPTION 304-1.1 This item shall consist of a cement-treated base(CTB)course composed of mineral aggregate and cement, uniformly blended and mixed with water. The mixed material shall be spread and shaped with a mechanical spreader, and compacted with rollers in accordance with these specifications and in conformance to the lines,grades, dimensions, and cross-sections shown on the plans. MATERIALS 304-2.1 Aggregate. The aggregate shall be select granular materials, comprised of crushed or uncrushed gravel and/or stone, or recycled crushed and graded portland cement concrete(PCC). The material shall be free of roots, sod, and weeds. The crushed or uncrushed aggregate shall consist of hard, durable particles of accepted quality, free from an excess of soft, flat, elongated, or disintegrated pieces, and objectionable matter. The method used to produce the aggregate shall ensure the finished product is as consistent as practicable. All inferior quality stones and rocks shall be wasted.If recycled PCC is used as the aggregate, it must meet the requirements for virgin aggregate. The percentage of wear of the crushed aggregate retained on the No.4(4.75-mm)sieve shall not be greater than 40%when tested in accordance with ASTM C131.The sodium sulfate soundness loss shall not exceed 10%, or the magnesium sulfate soundness loss shall not exceed 15%, after five cycles, when tested in accordance with ASTM C88. When tested in accordance with ASTM C136,the aggregate shall conform to the gradation(s)shown in the table below(titled Aggregate Gradation for CTB Material).An aggregate blend that meets the requirements of the table shall be selected by the Contractor and used in the final mix design. The final aggregate blend shall be well graded from coarse to fine within the limits designated in the table and shall not vary from the low limit on one sieve to the high limit on adjacent sieves, or vice versa. The portion of final aggregate blend passing the No.40(425 µm)sieve shall have a liquid limit of not more than 25 and a plasticity index of not more than six(6)when tested in accordance with ASTM D4318. Aggregate Gradation for CTB Material Percentage by Weight Passing Sieves Sieve Size Gradation A Gradation B 2 inch(50 mm) 100 1 100 1 No. 4(4.75 mm) 45- 100 55- 100 No. 10(1.80 mm) 37- 80 45- 100 No. 40(450 µm) 15 -50 25- 80 No. 80(210 µm) 0-25 10-35 1 Maximum nominal size of aggregate is 1 inch(25 mm). All aggregate samples required for testing shall be furnished by the Contractor at the expense of the Contractor. Sampling shall be performed by the Contractor in accordance with ASTM D75. 304-2.2 Cement. Cement shall conform to the requirements of ASTM C150,Type I. Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course AlP No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-1 FAA 150/5370-1 OG (7/21/2014)—MODIFIED 304-2.3 Cementitious additives. Pozzolanic and slag cement may be added to the CTB mix.If used, each material must meet the following requirements: a.Pozzolan.Pozzolanic materials must meet the requirements of ASTM C618, Class F, or N with the exception of loss of ignition,where the maximum shall be less than 6%. b. Slag Cement. Slag shall conform to ASTM C989, Grade 120. 304-2.4 Water. Water used in mixing or curing shall be potable, clean and free of oil, salt, acid, alkali, sugar,vegetable,or other deleterious substances injurious to the finished product. 304-2.5 Curing materials.For curing CTB placed under PCC pavement, use white-pigmented, liquid membrane-forming compound conforming to ASTM C309,Type 2, Class A or Class B (wax-based). ] COMPOSITION OF MIXTURE 304-3.1 General. The CTB material shall be composed of a mixture of aggregate, cementitious material, and water. Fly ash or slag cement may be used as a partial replacement for Portland cement. 304-3.2 Mix design. The mix design shall use a cement content that, when tested in the laboratory per ASTM D1633, produces a 7-day compressive strength between 400 pounds per square inch (2758 kPa) minimum and 800 pounds per square inch (5516 kPa) maximum. The 28-day strength shall not exceed 1000 pounds per square inch(6895 kPa). The mix design shall include a complete list of materials, including type, brand, source, and amount of cement,fine aggregate,coarse aggregate,water, and cementitious additives. Should a change be made in aggregate sources or type of cement, or if cementitious additives are added or deleted from the mix,production of the CTB mix shall be stopped and a new mix design shall be submitted. 304-3.3 Submittals.At least 30 days prior to the placement of the CTB,the Contractor shall submit certified test reports to the Engineer for those materials proposed for use during construction, as well as the mix design information for the CTB material.Tests older than six(6)months shall not be used.The certification shall show the ASTM or AASHTO specifications or tests for the material, the name of the company performing the tests, the date of the tests, the test results, and a statement that the material did or did not comply with the applicable specifications. The submittal package shall include the following: a. Source(s) of materials, including aggregate, cement, cementitious additives, curing, and bond- breaking materials. b. Physical properties of the aggregates, cement, cementitious additives, curing, and bond-breaking materials. c. Mix design: • Mix identification number • Aggregate gradation • Cement content • Water content • Cementitious materials content d.Laboratory test results: • Compaction and strength test procedures Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course AlP No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-2 FAA 150/5370-10G (7/21/2014)—MODIFIED • Laboratory compaction characteristics (maximum dry density and optimum moisture content) • Compressive strength at seven(7) days • Wet-dry and/or freeze-thaw weight loss, if applicable No CTB material shall be placed until the submittal is accepted in writing by the Engineer. During production,the Contractor shall submit batch tickets for each delivered load. EQUIPMENT All equipment necessary to mix,transport,place, compact, and finish the CTB material shall be furnished by the Contractor. The equipment shall be inspected and approved by the Engineer at the job site prior to the start of construction operations. 304-4.1 Mixing. Mixing shall be accomplished in a central mixing plant or in place, using single-shaft or multiple-shaft mixers. Agricultural disks or motor graders are not acceptable mixing equipment. 304-4.1.1 Central Mixing Plant. The mixer shall be a batch or continuous-flow type stationary mixer. The mixer shall be equipped with calibrated metering and feeding devices that introduce the aggregate, cement,water, and cementitious additives(if used)into the mixer in the specified quantities.If necessary, a screening device shall be used to remove oversized material greater than 2 inches (50 mm)from the raw aggregate feed prior to mixing. The Engineer shall have free access to the plant at all times for inspection of the plant's equipment and operation and for sampling the CTB mixture and its components. 304-4.1.2 Mixed in Place. Use any combination of machines or equipment that will produce the required results meeting the approval of the Engineer. Use a cement spreader which has an adjustable rate of flow and the capability of spreading the required amount of cement in one pass.Mix cement,aggregate and water with a self-propelled rotary mixer capable of mixing to a depth of 12". Correct any leakage of fluids and/or materials promptly or the Engineer may order such equipment removed and replaced with satisfactory equipment. Use equipment and methods for applying cement,water, and curing seal that does not damage the base. 304-4.2 Hauling. The mixed CTB material shall be transported from the plant to the job site in trucks or other hauling equipment having beds that are smooth,clean, and tight. Truck bed covers shall be provided and used to protect the CTB from rain. CTB material that becomes wet during transport shall be rejected. 304-4.3 Placing. CTB material shall be placed using a mechanical spreader or a machine capable of receiving, spreading, and shaping the mixture without segregation into a uniform layer or lift. The equipment shall be equipped with a strike-off plate capable of being adjusted to the specified layer thickness. It shall also be equipped with two end gates or cut off plates, so that the CTB may be spread in widths varying up to lane width. 304-4.4 Compaction. Compaction of the CTB layer shall be accomplished using one or a combination of the following pieces of equipment:tamping or grid roller;steel-wheeled roller;vibratory roller;pneumatic- tire roller,and/or vibrating plate compactor(for areas inaccessible to rollers).The number,type,and weight of rollers and/or compactors shall be sufficient to compact the mixture to the required density. 304-4.5 Finishing. Final trimming of the compacted CTB to meet surface requirements shall be accomplished using a self-propelled grader or trimming machine,with a mold board cutting edge,which is at least 12 feet(3.7 m)wide and is automatically controlled by sensors in conjunction with an independent grade control from a taut stringline. Stringline will be required on both sides of the sensor controls for the Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course A1P No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-3 FAA 150/5370-1 OG (7/21/2014)—MODIFIED pilot lane. For all other lanes, a single stringline on the outside and grade matching with previously completed adjacent lanes is permissible. CONSTRUCTION METHODS 304-5.1 Weather limitations. 304-5.1.1 Cold weather. Do not construct base when weather conditions will detrimentally affect quality of the finished course.Apply cement when the ambient temperature is a minimum of 40°F(4°C)and rising. Do not apply cement to aggregate materials that are frozen or contain frost. If ambient temperature falls below 40°F (4°C), protect completed cement-treated areas against freezing. Reprocess, reshape, and recompact damaged material. The CTB shall not be placed on frozen surfaces.Provide drainage to prevent water from collecting or standing on stabilized areas, and on the pulverized, mixed, or partially mixed materials. 304-5.1.2 Rain.The CTB may not be placed when it is raining.If unexpected rain occurs during placement, the layer should be quickly compacted. CTB material that becomes wet by rain during transport or placement shall be evaluated by the Engineer,and may be rejected. 304-5.2 Preparation of underlying course.The underlying course shall be checked by the Engineer before placing and spreading operations are started,to ensure that it is free of any ruts, depressions,or bumps and is finished to the correct grade.Any ruts or soft yielding places shall be corrected before the CTB mixture is placed. The underlying course shall be wetted in advance of placing the CTB layer. The final prepared grade prior to placing the CTB should be in a firm and moist condition free of frost. Use of chemicals to eliminate frost will not be permitted. To ensure proper drainage, placement of the base shall begin along the centerline of the pavement on a crowned section or on the highest elevation contour of a pavement with variable cross slope. 304-5.3 Grade control. Grade control between the edges of the CTB shall be accomplished at intervals of 50 feet(15 m) or less on the longitudinal grade and at 25 feet(7.5 m)or less on the transverse grade. 304-5.4 Handling, measuring, and batching - Central Mixing Plant Method. The continuous flow central plant site, layout, equipment, and provisions for transporting material shall assure a continuous supply of material to the work. Aggregate stockpiles shall be constructed in a manner that prevents segregation and intermixing of deleterious materials.Aggregates that are segregated or mixed with earth or foreign material will not be accepted. Continuous flow plants shall be equipped with feeders to automatically and accurately proportion aggregates and bulk cement, by weight. When bulk cement is used, the Contractor shall use a suitable method of handling the cement such as a chute,boot or other device,to prevent loss of cement between the weigh hopper and mixer. The device shall provide positive assurance that the specified cement content is present in each batch. 304-5.5 Mixing- Central Mixing Plant Method. Aggregate and cement may be proportioned either by weight or volume, and shall be mixed sufficiently to prevent the forming of cement balls when water is added. The mixing time shall be that required to secure a well-blended, uniform mixture of aggregate, cement, water, and pozzolan (if used). The minimum mixing time will be based on the uniformity and consistency of the mixture. 304-5.6 Placing—Central Mixing Plant Method. The CTB mixture shall be deposited on the moistened subgrade or subbase and spread into a uniform layer of specified width and thickness that,when compacted and trimmed, conforms to the required line, grade, and cross-section. The Contractor may install the CTB layer in single or multiple compacted lifts;however, each compacted lift must be no greater than 6 inches Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course AIP No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-4 FAA 150/5370-1 OG (7/21/2014)—MODIFIED (150 mm)thick.In multi-lift construction,the surface of the compacted lift shall be kept moist until covered with the next lift. Successive lifts shall be placed and compacted so that the required total depth of the CTB layer is completed within 12 hours. A single spreader may be used, provided it is capable of placing a uniform, full-depth layer of material across the full width of the base in one pass. Otherwise,two or more spreaders will be required, and shall be operated so that spreading progresses along the full width of the base in a uniform manner. 304-5.7 Mixing and Placing—Mixed In Place Method. Place the required quantity of aggregate on the prepared subgrade in a uniform layer. Spread aggregate on the subgrade in advance of the mixing operations only to the extent that processing can be completed within one week. Apply the required quantity of cement in a uniform spread on the aggregate in place and immediately blend the aggregate until the cement is uniformly distributed throughout the aggregate. Maintain the moisture content at or below the optimum moisture at the time of application of the cement. Do not apply cement on excessively windy days and apply only to such an area that all operations shall be completed on the same day during daylight hours. Immediately after the aggregate and cement have been thoroughly blended, apply water as needed and incorporate into the mixture. Control the application of the water so that there is no excessive concentration on or near the surface of the mixture. After the necessary water has been applied, continue mixing until a thorough and uniform mixture is obtained. Maintain the moisture content at the time of final mixing and during compaction within a range of optimum to optimum plus 1.5%as determined. Make sure that the moisture content in the mix does not exceed the quantity that will cause the base course to become unstable during compaction or finishing operations. 304-5.8 Compaction. Immediately upon completion of the spreading operations, the CTB material shall be thoroughly compacted using approved compaction equipment.At the start of compaction,the moisture content shall be within+2 percentage points of the specified optimum moisture. 304-5.9 Finishing. After completing compaction, the surface of the CTB layer shall be shaped to the specified lines, grades, and cross-section. During the finishing process, the surface shall be kept moist by means of fog-type sprayers. Compaction and finishing shall produce a smooth, dense surface, free of ruts, cracks,ridges, and loose material.All placement, compaction,and finishing operations shall be completed within two (2)hours from the start of mixing.Material not completed within the 2-hour time limit shall be removed and replaced at the Contractor's expense. CTB layer limits that extend beyond the edges of the new PCC surface course shall be rolled down or shaped to ensure the drainage is away from the new PCC surface course edge. 304-5.10 Construction joints.At the end of each day's construction, a transverse construction joint shall be formed that is a true vertical face(perpendicular to the centerline) and is free of loose material. Longitudinal construction joints (parallel to the centerline) shall be formed to a consistent, well-defined vertical edge that is free of loose material. The longitudinal joints shall be located so there is a 2-foot(0.6- m)minimum offset from planned joints in any overlying layer. While forming construction joints,the Contractor shall make sure the material in the joint area is adequately compacted and that the joints are finished level and even with the remainder of the CTB layer. 304-5.11 Curing.The compacted and finished CTB shall be cured with the approved curing agents as soon as possible and in no case later than two (2) hours after completion of the finishing operations. The layer shall be kept moist using a moisture-retaining cover or a light application of water until the curing material is applied. Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course AIP No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-5 FAA 150/5370-10G (7/21/2014)—MODIFIED When a liquid membrane-forming curing compound is used as the curing agent, the surface of the CTB layer shall be uniformly sprayed with the curing compound at the rate of one gallon(3.8 liters)to not more than 200 square feet(18.6 m2)to obtain a uniform cover over the surface. The spraying equipment shall be of the fully atomizing type equipped with a tank agitator. The curing compound shall be thoroughly and uniformly mixed with the pigment in the storage tank. During application, the compound shall be stirred continuously by mechanical means.Hand spraying of odd widths or shapes and CTB surfaces exposed by the removal of forms is permitted. The curing seal shall be maintained and protected until the pavement is placed.If the surface of the finished CTB and/or the curing seal becomes damaged, additional curing material shall be applied at the time it is damaged or when the damage is first observed. 304-5.12 Protection. Completed portions of the cement-stabilized area may be opened to local traffic provided the curing process is not impaired and to other traffic after the curing period has elapsed,provided that the cement-stabilized course has hardened sufficiently to prevent surface marring or distortion by equipment or traffic. Do not permit construction equipment on the area during protection and curing periods. Necessary cement and water may be hauled over the area with pneumatic-tired equipment on approval of the Engineer.Protect finished portions of cement stabilized base from traffic of equipment used in constructing adjoining sections in a manner to prevent marring or damaging completed work. The CTB shall also be protected from freezing at all times. 304-5.13 Bond-breaker. When the CTB is to be placed directly beneath PCC, the entire surface of the CTB shall be coated with a de-bonding compound applied in a quality sufficient to prevent bonding of the PCC pavement to the base course. If an impervious membrane or asphalt emulsion is used as a curing material, additional applications of curing materials may be required. The Contractor shall be responsible for selecting the de-bonding compound and determining the necessary application rate. The de-bonding compound shall be approved by the Engineer prior to being incorporated into the work. MATERIAL ACCEPTANCE 304-6.1 Acceptance sampling and testing. All acceptance sampling and testing, with the exception of coring for thickness determination,necessary to determine conformance with the requirements specified in this section will be performed by the Engineer. The Contractor shall provide the required CTB samples during construction for acceptance testing purposes. The samples shall be taken in the presence of the Engineer. Testing organizations performing these tests shall meet the requirements of ASTM D3666. All test equipment in Contractor-furnished laboratories shall be calibrated by the testing organization prior to the start of operations. The CTB layer shall be tested for density,thickness, grade, and surface tolerance on a lot basis, with a lot consisting of either (1) one day's production not to exceed 2,000 square yards (1700 sq m), or(2) a half day's production,where a day's production consists of 2,000 to 4,000 square yards (1675 to 3350 m2). Each lot shall be divided into four equal sublots. Within each sublot, one density test, one thickness measurement, and continuous surface straightedge tests (surface tolerance testing) shall be performed, as described below. Sampling locations shall be determined by the Engineer per ASTM D3665. If only three sublots are produced,the three sublots shall constitute a complete lot.If one or two sublots are produced for the same reason,they shall be incorporated into the next or previous lot,and the total number of sublots shall be used in the acceptance criteria calculation. Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course AIP No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-6 FAA 150/5370-10G (7/21/2014)—MODIFIED End-of-production sublots (that is, sublots associated with the final placement of CTB for the project and are less than a complete lot) shall be handled as (1) three sublots shall constitute a lot, or (2) one or two sublots shall be incorporated into the previous lot. If the mixed in place method is used additional sampling and testing may be required and performed by the Engineer to verify that mixing and compaction of materials are extending uniformly across the limits of construction. Additional samples may be taken every 200 linear feet in the outermost five feet of product placement adjacent to existing pavements. If any samples fail the test defined below additional samples will be taking to determine the extents in which the construction material becomes uniform. All areas determined not to be uniform along the outer edges will be removed at the contractor's expense and replaced with material from a Central Mixing Plant and resampled and tested in accordance with these specifications for acceptance. 304-6.1.1 Density testing. CTB samples shall be taken from each sublot and used to create laboratory test specimens representing the various sublots. The specimens shall be compacted and tested for density and moisture content per ASTM D558.The density for each sublot comprising a lot,shall be used to determine an average density for the lot,which will serve as the basis for acceptance of the lot for density. Within each sublot in the field, one in-place density test shall be performed in accordance with ASTM D6938. The location of the test shall be randomly selected per ASTM D3665.The in-place density for each sublot comprising the lot shall be averaged and compared with the corresponding average lot density. Acceptance criteria for CTB density are provided in paragraph 304-6.2.1. All testing shall be clone by the Engineer. 304-6.1.2 Thickness testing. The CTB shall be tested for thickness using the same lot and sublots established for density testing.After three(3)days of curing, one 3-inch(75 mm)diameter core per sublot shall be obtained from a random location,per ASTM D3665. The thickness of each sampled core shall be determined using the caliper measurement procedures provided in ASTM C 174. The average thickness for the lot shall be determined using the individual sublot core thicknesses. Acceptance criteria for CTB thickness are provided in paragraph 304-6.2.2.At all locations where cores have been drilled,the resulting core holes shall be filled by the Contractor with CTB or non-shrink grout. 304-6.1.3 Grade testing. The elevations of the finished CTB shall be surveyed every 25 feet (7.5 m) on both sides of the CTB lane as soon as it has hardened sufficiently. Acceptance criteria for CTB grade are provided in paragraph 306-6.2.3. 304-6.1.4 Surface tolerance testing.After the CTB has hardened sufficiently,it shall be tested for surface tolerance with a 12-foot(3.7-m)straightedge or other approved measuring device for tolerances outlined in paragraph 304-6.2. 304-6.2 Acceptance criteria. Acceptance of CTB will be based on density, thickness, grade, and surface tolerance,as described in the paragraphs below. 304-6.2.1 Density requirements. For density, each lot of compacted material will be accepted without adjustment if the average in-place density of the lot is equal to or greater than 98%of the average laboratory density determined for the lot. Each lot of compacted CTB shall be accepted and payment adjusted in accordance with the table below. Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course Alp No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-7 FAA 150/5370-1 OG (7/21/2014)—MODIFIED Sliding Pay Scale Factors For Density Average Dry Density(%) Payment(%) 98.0 and greater 100 97.0-97.9 95 96.0-96.9 90 95.0-95.9 75 Less than 95.0 Reject If the average density is below 95%, the lot will be rejected and shall be removed and replaced at the Contractor's expense. In multi-layer construction, density shall be tested for each lift, and all lifts within a rejected lot shall be removed and replaced.No payment shall be made for removed lifts.Replacement lifts shall be paid in accordance with this section. 304-6.2.2 Thickness requirements. The completed thickness shall be as shown on the plans. When the average lot thickness is not deficient by more than 1/2 inch(12 mm)from the plan thickness, full payment shall be made. If the average lot thickness is deficient by more than one inch(25 mm),it shall be removed and replaced at the Contractor's expense. When such measurement is deficient by more than 1/2 inch(12 mm)but less than one inch(25 mm)from the plan thickness, one additional core shall be taken at random from each sublot within the lot. The thickness of these additional cores shall be determined as indicated in paragraph 304-6.1.2.A new average lot thickness shall be recomputed based on these additional cores and the original cores taken from each sublot. If the recomputed average lot thickness is not deficient by more than 1/2 inch(12 mm) from the plan thickness, full payment shall be made. If the average lot thickness is deficient by more than 1/2 inch (12 mm) from the plan thickness, the entire lot shall be removed and replaced at the Contractor's expense or shall be permitted to remain in-place at an adjusted payment of 75% of the contract unit price. When the measured thickness is more than that indicated on the plans, it will be considered as conforming to the requirements, provided the surface of the completed CTB layer is within the established grade and surface tolerance requirements. 304-6.2.3 Grade requirements. When the completed surface is higher than 1/2 inch (12 mm) above the grade shown in the plans, the surface shall be trimmed, at the Contractor's expense, with an approved grinding machine to an elevation that falls within a tolerance of 1/4 inch(6 mm) or less. 304-6.2.4 Surface tolerance requirements. The finished surface shall not vary more than 3/8 inch(9 mm) when tested with a 12-foot(3.7-m)straightedge applied parallel with,or at right angles to,the centerline of the CTB area.Areas in the CTB showing high spots greater than 3/8 inch(9 mm)over 12 feet(3.7 m)shall be marked and immediately trimmed with an approved grinding machine. Such trimming shall be at the Contractor's expense. METHOD OF MEASUREMENT 304-7.1 Cement-treated base course. The quantity of cement-treated base course will be determined by measurement of the number of square yards(m2)of CTB actually constructed and accepted by the Engineer as complying with the plans and specifications. 304-7.2 Portland Cement for Cement Treated Base. The quantity of Portland cement for cement-treated base will be determined by measurement of the number of hundred weight of CTB actually constructed and accepted by the Engineer as complying with the plans and specifications. Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course AIP No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-8 FAA 150/5370-1 OG (7/21/2014)—MODIFIED BASIS OF PAYMENT 304-8.1 Cement-treated base course. Payment shall be made at the contract unit price per square yard (m2) for cement-treated base course. Payment shall be made at the contract unit price per hundred weight for Portland cement for cement treated base. This price shall be full compensation for furnishing all materials, including cement; for all preparation, manipulation, placing, and curing of these materials; and for all labor, equipment,tools, and incidentals necessary to complete the item. Each lot of CTB material will be accepted for density at the full contract price adjusted in accordance with paragraph 304-6.2.1. Item P-304.1 Cement Treated Base Course(10"Depth)-per square yard Item P-304.2 Cement Treated Base Course(12"Depth)—per square yard Item P-304.3 Cement Treated Base Course(14"Depth)—per square yard Item P-304.4 Portland Cement for Cement Treated Base—per hundred weight Item P-304.5 Cement Treated Base Course(12"Depth Mixed In Place)—per square yard Item P-304.6 Cement Treated Base Course(10"Depth Mixed In Place)—per square yare TESTING REQUIREMENTS ASTM C88 Standard Test Method for Soundness of Aggregates by Use of Sodium Sulfate or Magnesium Sulfate ASTM C131 Standard Test Method for Resistance to Degradation of Small-Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine ASTM C136 Standard Test Method for Sieve or Screen Analysis of Fine and Coarse Aggregate ASTM C174 Standard Test Method for Measuring Thickness of Concrete Elements Using Drilled Concrete Cores ASTM D75 Standard Practice for Sampling Aggregates ASTM D558 Standard Test Methods for Moisture-Density (Unit Weight) Relations of Soil- Cement Mixtures ASTM D1633 Standard Test Methods for Compressive Strength of Molded Soil-Cement Cylinders ASTM D6938 Standard Test Method for In-Place Density and Water Content of Soil and Soil- Aggregate by Nuclear Methods(Shallow Depth) ASTM D3665 Standard Practice for Random Sampling of Construction Materials ASTM D3666 Standard Specification for Minimum Requirements for Agencies Testing and Inspecting Road and Paving Materials ASTM D4318 Standard Test Methods for Liquid Limit, Plastic Limit, and Plasticity Index of Soils Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course Alp No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-9 FAA 150/5370-1 OG (7/21/2014)—MODIFIED MATERIAL REQUIREMENTS ASTM C150 Standard Specification for Portland Cement ASTM C309 Standard Specification for Liquid Membrane-Forming Compounds for Curing Concrete ASTM C618 Standard Specification for Coal Fly Ash and Raw or Calcined Natural Pozzolan for Use in Concrete ASTM C989 Standard Specification for Slag Cement for Use in Concrete and Mortars END OF ITEM P-304 Rehabilitate Air Carrier and GA Apron-Ph 2 Technical Specifications Augusta Regional Airport,Augusta,Georgia Item P-304 Cement Treated Base Course AIP No.3-13-0011-042-2018 Modification of Standard-November 14,2018 P-304-10 AUGUSTA RICHMOND COUNTY Hardie Davis,Davis, Jr., Mayor ATTEST: t t t '7, t It , / A !iij /41 gii _. 4/ Jff/ - - -V ',. • ' -•-7 '''' - 0 Lena Bonn/-r, Clerk t -,- : a of s Z1 0 ': s'''11:4WighSgtiet, 4( Approved as to Form: , /(,, hilitekayi 37a/if Andrew Mackenzie, Esq. 1