e.Surface Requirements. The graded earth surface and the finished subgrade surface, after being properly compacted, shall be checked by the use of blue-tops, strings, and template and all portions not within the following tolerances shall be corrected: Variations from the designated grade up to plus 1/2 inch {13 mm} or minus 1 inch {25 mm} will be allowed provided the variation does not increase or decrease more than 1/2 inch {13 mm} in 100 feet {40 m}; however, at bridge structures a plus tolerance will require additional fine grading to prepare a suitable grade tie. The finished surface shall not vary at any point more than 1/2 inch {13 mm} in any 25 foot {7.5 m} section from a taut string applied parallel to the surface and the roadbed centerline, or more than 1/2 inch {13 mm} from a template placed at right angles to the roadbed centerline. The template shall be of a rigid frame, adjustable metal type, accurately set, and at least as long as the width of roadbed being checked up to 30 feet {9 m}. Additional widths may be checked by the use of string and level. The Contractor shall furnish template, string, and necessary personnel to handle same under the direction of the Engineer. No subbase or other layer shall be placed on the roadbed until it meets specified requirements for alignment, grades, cross section, and density. Where a Permeable Asphalt Treated Base (PATB) layer is to be placed (Pay Item 327-E), the finished subgrade elevations shall not vary from design by more than 0.03 feet {10mm} based on rod and level survey readings taken at a minimum of five locations across each lane (edge, outer wheel path, midlane, inner wheel path, and inside edge of lane) at longitudinal intervals not greater than 50 feet {15 m}. Surface irregularities shall not exceed 1/4 inch {7 mm} between two points longitudinally or transversely using a 10-foot {3 m} straightedge.
f.Protection and Maintenance of Roadbed. The Contractor shall be responsible for the protection and maintenance of any existing roadbed or any roadbed constructed during the contract. The roadbed shall be maintained free from ruts and other depressions, in a smooth and compacted condition, and true to lines and grades. Any of the Contractor's hauling and other equipment used in such a way as to cause excessive rutting or raveling of the roadbed material shall either be removed from the work or suitable runways shall be provided to prevent rutting. No payment will be made for the protection and maintenance of the roadbed, such being considered incidental to the work. However, if a contract requires an improved roadbed to be placed on an earth surface constructed under a previous contract, the surface shall be repaired to the extent directed under the requirements of Section 210.
230.04 Method of Measurement.
Measurement and payment for the materials used in the construction of improved roadbed and modified roadbed will be at the contract unit price for unclassified or Borrow Excavation as provided in the contract. No separate measurement will be made for reshaping of a roadbed constructed under a previous contract, such being considered incidental to the work covered by this Section; however, any additional material required to restore the roadbed to the typical section will be measured and paid for under the appropriate item of material ordered used.
a.Item 230-A. Measurement for the item of Roadbed Processing (which is the additional processing over and above that normally required by Section 210) will be in 100 foot {100 m} roadbed stations for each layer processed. The length of roadbed stationing will be in 100 foot {100 m} stations and fractions thereof to the nearest foot {meter} of any main roadbed in accordance with the following: on each roadbed separately for divided highways having more than one roadbed; on each half of a roadbed of a four lane facility constructed with a positive divider between opposing traffic; on ramps; on frontage, connecting, and crossing roads; and on widening work each roadbed as defined above whether widening is on one side or both sides. No measurement will be made for increased widths, lanes, turnouts, spurs, or crossovers when shown on the plans or for variations in widths due to changes in slopes. For additional areas over those shown on the plans, measurement will be allowed in the ratio of the increase in width to the standard width shown on the plans. The total measurement shall be the sum of the lengths measured along the center of the main roadbed or along each separate roadbed of divided highways, plus the measured ramps from where the ramp centerline crosses the edge of shoulders, plus (if any) the lengths of crossroads, connecting roads, and frontage roads. The length of modified roadbed or improved roadbed constructed under a previous contract and actually reprocessed will be measured for payment. SECTION 231 STABILIZED ROADBED
b.Item 230-B. Measurement for the Item of Roadbed Processing (which is the additional processing over and above that normally required by Section 210) will be by the square yard {square meter} for each layer processed.
230.05 Basis of Payment.
a.Unit Price Coverage. Each separate layer of roadbed processed and accepted, and measured as noted above, will be paid for at the contract unit price, which shall be full compensation for the mixing, remixing, watering, and re-processing necessary to obtain and maintain the required grade, section, and density as noted herein in this Section and includes all equipment, tools, labor, and incidentals necessary to complete the work as described herein.
b.Payment will be made under Item No.: 230-A Roadbed Processing - per roadbed station 230-B Roadbed Processing – per square yard SECTION 231 STABILIZED ROADBED
231.01 Description.
This Section shall cover the work of preparing a roadbed for receiving a base and pavement structure by stabilizing it with an approved local or commercial material. The work shall consist of scarifying the roadbed, incorporating the stabilizing material into the roadbed, and compacting the roadbed to the proper grade, section, and density. When stabilizing material is present on the roadway surface, the work shall consist of incorporating the stabilizing aggregate into the roadbed and compacting the roadbed surface to the proper grade, section, and density.
231.02 Materials.
The stabilizing material to be incorporated shall be an approved local or commercial material of the type provided by the plans or proposal,
231.03 Construction Requirements.
a.General. Choice of equipment to perform the work under this Section shall, in general, be that of the Contractor provided such produces the desired results noted herein and does not damage or injure any completed work or facility designated to be incorporated into the work.
b.Preparation of the Roadbed. The roadbed shall have been prepared in accordance with the provisions of Section 210. The designated sections of the roadbed of the width specified on the plans of both cuts and fills shall then be scarified or otherwise loosened for the depth specified by the plans or as directed. Certain equipment capable of mixing the stabilizing material and the material in place without pre-working the in-place material may permit combining this step with the requirements of Subarticle (c) below.
c.Placement and Processing of Stabilizing Material. The approved stabilizing material shall be spread uniformly over the roadbed, at the rate specified on the plans or as directed, by approved spreading equipment. The stabilizing material shall then be mixed with the subgrade material until uniform in color and texture as directed and compacted to the required grade, section, and density.
d.Density and Surface Requirement. Density and surface requirements shall be the same as specified in Subarticle 230.03(d) and (e), respectively.
e.Protection and Maintenance of Roadbed. Protection and maintenance of roadbed shall be the same as specified in Subarticle 230.03(f).
231.04 Method of Measurement.
All accepted stabilizing material ordered and accepted will be measured in cubic yards {cubic meters}, loose measurement, or per ton {metric ton}.
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Source: 2026 Standard Specifications for Highway Construction, 2026 Edition. Pages 152–153 of 826. View official source ↗