302FULL DEPTH RECLAMATION WITH PORTLAND CEMENT

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No full depth reclamation shall be constructed when the ambient temperature is below 40 ⁰F without written permission of the Engineer. Working on full depth reclamation construction will not be allowed when it is raining or the possibility or rain is imminent. The Engineer will decide base on weather reports if the possibility of rain exists.

The Engineer will prohibit the use of any piece of equipment that will not, or does not, produce acceptable results. The Contractor shall not begin the distribution of the cement until the Engineer informs the Contractor that the proposed equipment and method of monitoring cement placement is adequately described in the quality control plan. Equipment shall include a mechanical cement spreader of a type that has an adjustable rate of flow and will distribute the cement uniformly at the required rate in one pass. Pneumatic distribution of cement is prohibited. A mechanical mixer shall be used that is capable of pulverizing and mixing the existing pavement, base and sub-grade to the required depth. The mechanical mixer shall be capable of pulverizing the material so that 100 % passes a 2-inch sieve. The mixer shall have a metered water system for adding water directly into the mixing chamber. Water shall not be applied from equipment that is not a part of the mixer.

Except by written permission of the Engineer, the length of roadbed pulverized at any time shall not exceed the length that can be completely pulverized, mixed and compacted in the same working day.

The width and depth of the required pulverizing and mixing will be shown on the plans. The depth of pulverizing shall be controlled to ensure that the finished thickness will be within the required tolerance limits. The pulverizing and mixing shall break up the existing roadbed to the extent that 100 % by weight passes a 3-inch sieve, a minimum of 95 % passes a 2-inch sieve and a minimum of 50 % passes the No. 4 sieve. The moisture content shall be maintained within ± 2 % of the theoretical optimum moisture content unless approved otherwise by the Engineer. The Engineer will check the gradation at least once for each 2000 linear feet or fraction thereof of each lane. Preliminary pulverization and mixing of the roadbed materials will be allowed prior to final pulverization and mixing of the roadbed materials and cement to ensure uniformity of the mixture. The Engineer will monitor the pulverization in accordance with BMT-80, “Rate of Spread and Pulverization of Cement Stabilized Soil”.

Spreading of the cement shall be done to produce a uniform distribution. The amount of cement placed shall not vary more than 5 % by weight from the approved Job Mix Design. Cement dust shall be controlled by the Contractor so that dust is kept within the confines of the construction limits. Spreading of the cement when the wind or other weather conditions are unfavorable will not be permitted. Spreading of the cement by motor grader will not be acceptable. Cement shall be applied in a limited area so that all the operations including compaction, finishing, and curing can be continuous and completed in daylight hours, within three hours of the application of the cement. Only the equipment that is used in spreading and mixing will be allowed to pass over the spread cement before it is mixed into the existing materials. Cement that has been displaced shall be replaced before mixing is started.

Water shall be mixed into the mixture of cement and pulverized roadbed materials. The addition of water and the mixing shall be completed in one continuous pass. The mixture of the water, cement, and pulverized roadbed materials shall be within the tolerance limits of theoretical optimum moisture content and shall be suitable for immediate compaction without further mixing or grading. A gage or gages shall be provided to allow the continuous monitoring of the amount of water that is applied. FULL DEPTH RECLAMATION WITH PORTLAND CEMENT 171

When the mixer will handle only a part of the roadbed width within a single lane, the successive increments shall be limited in length so that a cold joint will not be formed within the lane being constructed and the full width of lane of treated material will be promptly mixed, compacted, and finished. When the moisture content of the uncompacted mixture exceeds the specified tolerance for compaction, the entire affected section shall be reconstructed at the Contractor’s expense.

The pulverizing, mixing, and compaction shall be a continuous operation. The compaction of the mixture of water, cement, and roadbed materials shall begin within 30 minutes after the final mixing. The mixture shall be compacted to 96.0% of theoretical maximum density as established in the approved Job Mix Design in accordance with AASHTO T 134. The in-place density will be measured in accordance with the requirements given in AASHTO T 310, Direct Transmission Method only. The in-place density will be measured at least once for each 1000 linear feet or fraction thereof of each lane. Compaction and finishing shall be completed within a period of two hours after the initial mixing of the cement. After the mixture has been compacted, the surface shall be shaped to the required lines, grades, and cross sections and within the required tolerances. During the shaping, light scarifying may be necessary to prevent the formation of compaction planes. Broom dragging or clipping of the surface may be required as a part of the process of shaping the surface during compaction. The surface material shall be maintained at the specified moisture content during finishing operations. At the end of each day’s construction, a clean, straight, vertical, transverse construction joint shall be formed by cutting back to the full width and thickness of completed work.

Areas of the full depth reclamation that are not within the required tolerances of thickness, density, and surface finish shall be reconstructed as directed by the Engineer without additional compensation. The amount of cement required for reconstruction will be in accordance with the approved Job Mix Design.

The Contractor shall furnish and use a square piece of canvas that is one square yard in size for checking the spread rate. The canvas shall be weighed prior to cement placement each time placement rates are checked. After weighing, the canvas shall be placed ahead of the spreading operation. The canvas and cement shall be weighed after the spreader has passed over the canvas. The Contractor shall perform this measurement in the presence of the Engineer and report the measured spread rate to the Engineer. Adjustments shall be made and repeated testing will be required to ensure that the required rate is being placed. The cement spread rate shall be checked each day before beginning production placement and for each 2000 linear feet or fraction thereof of spreading in each lane. The Engineer will record the amount of cement placed in accordance with BMT-80, "Rate of Spread and Pulverization of Cement Stabilized Soil".

The thickness of the reconstructed roadbed will be checked by the Engineer at intervals of one test per 200 feet or fraction thereof of lane, or more often if necessary. The thickness of the entire reconstructed layer or layers shall not vary by ± 1 inch from that shown on the plans. Any section deficient by more than 1 inch shall be immediately reconstructed in accordance with all of the requirements given in this Section for full depth reclamation. Any section out of tolerance shall have additional cement added to correct the composition of the full depth reclamation mixture and shall be remixed and recompacted to the required depth, width and density.

The Contractor shall be responsible for roadbed grade controls. The finished surface shall not vary more than 1/4 of an inch from a 16-foot straightedge placed anywhere on the surface parallel to the centerline of the roadbed. The finished surface shall not vary more than ¼ of an inch from a 10-foot straightedge placed anywhere on the surface perpendicular to the centerline of the roadbed. The cross slope shall not vary by ± 0.50 % from the required slope as shown on the plans. The surface finish shall be checked at least twice within an intervals not to exceed 100 feet along the roadway. High spots in the finished surface may be corrected by motor grader or planer SOIL AND AGGREGATE MATERIALS FOR MISCELLANEOUS USE 172

without additional compensation, provided the resulting thickness is within the allowable tolerances.

The Contractor shall cover the finished surface with a prime coat within 24 hours from completion of compaction. The prime coat shall be maintained until a pavement layer or additional surface treatment is applied. The prime coat shall be as specified in the plans and shall be placed and paid in accordance with the requirements given in Section 401.

Any subgrade deficiencies shall be determined by the Engineer. The Contractor will be given a specific time to repair any deficiencies without any additional compensation.

Completed sections of the full depth reclaimed roadbed may be opened when necessary to lightweight local traffic, provided the surface has hardened sufficiently to prevent marring or distorting of the surface, and provided the curing is not impaired. Construction equipment shall not operate on the full depth reclamation sections except as necessary to discharge into the spreader during paving operations. If the full depth reclaimed roadbed is impaired by premature opening to traffic, the entire affected section shall be reconstructed at the Contractor’s expense.

302.04Method of Measurement

Full Depth Reclamation will be measured in units of square yards. The length of a lane will be measured along the center of the lane. The width of a lane will be the width shown on the plans. Additional areas required for crossovers, turnouts, etc., will be determined by the measurement of the length and width along the surface of the reclaimed area. Cement will be measured in units of tons.

302.05Basis of Payment

The contract unit price for Full Depth Reclamation shall be full compensation for furnishing all materials (except Portland cement and Bituminous Treatment for curing) equipment, tools, labor, and incidentals necessary to complete the work. The contract unit price for Portland cement for Roadbed Reclamation shall be full compensation for furnishing and applying the cement to complete the work of Full Depth Reclamation. Payment will only be made for the actual amount of cement applied to the reclaimed roadbed. Additional soil or aggregate material required to construct the roadbed to the required plan grade and section, and any unsuitable material excavated, will be measured and paid for under the appropriate item of Unclassified Excavation or Borrow.

302-A Full Depth Reclamation, ___ inches Thick - per square yard 302-B Portland Cement for Full Depth Reclamation - per ton SOIL AND AGGREGATE MATERIALS FOR MISCELLANEOUS USE

305.01Description

This Section shall cover the work of furnishing and incorporating a soil or aggregate material of the type specified into the work at the locations shown on the plans or designated by the Engineer. The type of material may be a local material, such as borrow or selected soil, or commercial material, such as crushed aggregate, or any combination thereof to produce a material consistent with the requirements of the type material specified. The intent of this Section is to provide material for use in localized areas for patching, leveling, or minor widening work. Layers of material of nominal depth and width should be placed under the appropriate Section of the Standard Specifications.