GENERAL REQUIREMENTS FOR BASES 301.03
301.01 Description
This section consists of the general requirements for the construction of bases.
301.02 Materials
Make necessary preliminary investigations to locate the proposed source of acceptable material. If available, the Contractor may inspect Department -obtained information related to subsurface investigations in accordance with Subsection 102.06, “Examination of Plans, Specifications, Special Provisions, and the Work Site.” Provide soils and aggregates with maximum and in -place densities in accordance with Subsection 202.0 4.A(5), “Compaction of Fill” unless otherwise required by the Contract.
301.03 Equipment
A.Mixing Equipment
1.Traveling Plants Provide single or multiple -pass traveling plants approved by the Resident Engineer. Ensure the traveling plants are capable o f pulverizing and mixing the material (identified in the job -mix formula) in accordance with Chapter 300, "Bases," and Chapter 700, "Materials." Mount the plant on wheels or on treads that will not damage the subgrade. If used, ensure that a single -pass machine is designed to pick up material from a windrow or blanket and is capable of picking up and mixing the material (separated from the mixing table) during at least half of the mixing cycle. Ensure the plant has equipment for metering and inserting liquids into the mixture in accordance with the specified mixture or mix design. Repair equipment leaks immediately.
2.Stationary Plants Provide stationary plants of the following types: Batch mi xing, that uses a revolving blade or rotary drum mixer, or Continuous mixing. Proportion all the ingredients in the job -mix formula by weight or volume and provide access to the Resident Engineer to verify the proportions in each batch of a batch mixer, or the rate of flow of a continuous mixer. Set the charge and mixing time in a batch mixer, or the rate of feed to a continuous mixer, to completely mix the materials. Ensure both plant types deliver a uniform mixture.
301.04 General Requirements for Bases
176 B. Compactors Use the following equip ment to achieve uniform density across the base or subbase in accordance with Subsection 202.04.A(5), “Compaction of Fill ” unless otherwise specified: Non -vibratory steel -wheeled roller, Vibratory compactor, Pneumat ic tired roller, Tamping type roller, or Any combination of the above equipment.
C.Sprinklers Ensure sprinklers discharge water uniformly and continuously.
D.Distributors and Supply Tanks Ensure distributors and supply tanks meet the requirements of Subsection 401.3.A, "Distributors and Supply Tanks."
301.04 Construction Methods
A.Tolerances Provide the required subgrade, subbase, and base in accordance with the following:
1.Surface Elevation and Smoothness Finish the subgrade, subbase, and base to elevations within ½ in [13 mm] of the elevations shown on the Plans. Ensure the surface smoothness is within ½ in [13 mm] in 10 ft [3 m]. Test for surface smoothness by placing a 10 ft [3 m] straightedge between any two contacts on the finished surface and measuring the distance from the surface to the straightedge.
2.Width and Thickness Finish subbases and bases to the minimum width shown on the Plans or directed by the Resident Engineer. Ensure an average job thi ckness within ¼ in [6 mm] of the thickness shown on the Plans. The Resident Engineer will determine the average job thickness by measuring the completed thickness at intervals of no more than 1,000 ft [300 m] in each driving lane. For individual measurem ents that exceed the plan thickness by more than ½ in [13 mm], the Resident Engineer will use the Plan thickness plus ½ in [13 mm]. For individual measurements of thickness that measure less than the Plan thickness by more than ½ in [13 mm], the Resident Engineer will require the Contractor to correct the thickness and rework the material.
B.Corrections Correct material dimensions that exceed the specified tolerance by methods approved by the Resident Engineer, at no additional cost to the Department. AGGREGATE BASE 303.03
301.05 Method of Measuremen T — Vacant
301.06 Basis of Payment
The Department will consider the cost of water to be included in the contract unit price for the appropriate existing Base pay item. SECTION 303 AGGREGATE BASE
303.01 Description
This work consists of providing and placing one or more layers of aggregates, and specified additives, on a prepared subgrade or subbase using conventional equipment and methods for incorporating water into th e aggregate base material and spreading it onto the subgrade. When plant mixed aggregate base is required by the Contract, the work will be performed by incorporating water into the aggregate base material with specialized equipment and methods away from the subgrade, and using specialized equipment for spreading the aggregate material onto the subgrade.
303.02 Materials
Provide aggregate material for the gradation type shown on the Plans (Type A, Type B, or Type C) in accordance with Subsection 703.01, “Aggregate for Aggregate Base.” Do not change the approved gradation type or source during aggregate production, unless the Engineer approves another gradation type or source in writing.
303.03 Equipment
A.Stationary Plant Provide a central mixing plant of the pugmill type, rotary drum type, or continuous type of mixer. Establish stationary plant location within reasonable proximity to the project in order to deliver the aggregate base material at the proper moisture and consistency requirements.
B.Traveling Plant Provide a traveling plant of the type that picks up the material from a windrow or from a blanket of loose material. The mixer may be of the pugmill or auger type, or of the transverse shaft type that mixes the materials by means of revolving paddles that lift all the loose material from the working area. Ensure the traveling plant has provisions for introducing the water at the time of mixing, through a metering device, or by other approved methods, and can apply the water by means of controls which will supply a uniform ratio of water in the approximate amount required for optimum moisture.
Source: Oklahoma Standard Specifications for Highway Construction, 2019 Edition. Pages 189–190 of 935.