306.01 306-1 SECTION 306 RECONDITIONING DESCRIPTION
306.01 This work consists of blading, shaping, wetting, and compacting the existing subgrade
with moisture and density control. CONSTRUCTION REQUIREMENTS
306.02 The top 6 inches of the existing subgrade shall be reconditioned by blading and rolling.
Sufficient water shall be added to meet the density requirements as specified in the Contract. The reconditioned surface shall not vary above or below the lines and grades as staked by more than 0.08 foot. The surface shall be tested for smoothness and density before the application of any base course material. Where asphalt -surfacing materials are to be placed directly on the subgrade, the subgrade plane shall not vary more than 0.04 foot. All irregularities exceeding the specified tolerance shall be corrected to the satisfaction of the Engineer at no additional cost to the Department. The surface shall be satisfactorily maintained until base course has been placed. METHOD OF MEASUREMENT
306.03 Reconditioning will be measured by the square yard of subgrade, including auxiliary
lanes, and shall include blading, shaping, scarifying, compacting the subgrade, finishing, and maintenance of the finished surface. BASIS OF PAYMENT
306.04 The accepted quantities of reconditioning will be paid for at the contract unit price for
reconditioning. Payment will be made under: Pay Item Pay Unit Reconditioning Square Yard Water will not be measured and paid for separately but shall be included in the work. 306.04 306-2 THIS PAGE INTENTIONALLY LEFT BLANK 307.01 307-1 SECTION 307 LIME TREATED SUBGRADE DESCRIPTION
307.01 This work consists of treating the earth subgrade by combining lime and water with the
pulverized soil subgrade material to the specified depth and compaction requirements as shown on the plans. MATERIALS
307.02 Lime. Lime for lime treated subgrade shall be applied in slurry form. Dry application
of lime will not be allowed unless otherwise approved by the Engineer. Commercial lime slurry shall be a pumpable suspension of solids in water. Lime for lime treated subgrad e shall conform to the requirements of ASTM C977 and rate of slaking test for moderate reactivity per ASTM C110 and shall be the product of a high -calcium limestone as defined by ASTM C51.
307.03 Water. Water used for mixing or curing shall be per subsection 712.01, with the
additional requirement that the sulfate content shall be less than 500 ppm. CONSTRUCTION REQUIREMENTS
307.04 General. The Contractor shall construct one or more compacted courses of treated
material, to the depth specified in the Contract. The treated material shall be a uniform blend of soil, lime, and water, free from loose or segregated areas. It shall have uniform density and moisture content and be void of all vegetation and other organic or man -made material. The subgrade shall be well bound for its full depth and width wit h a smooth surface suitable for placing subsequent courses. The Contractor shall re gulate the sequence of the work to accurately apply and uniformly blend the lime at the designated rate and rework the courses as necessary to meet the above requirements. The Contractor shall submit a mix design to the Engineer for approval, before constructing the test section. The Contractor shall mix hydrated or quicklime with water to produce lime slurry at the job site with equipment specifically manufactured for this purpose. Excessive aeration of lime slurry will not be permitted. The lime- treated subgrade shall not be mixed when it is raining, or when the subgrade material is frozen. The lime- treated subgrade shall not be mixed or compacted if the temperature of the lime or soil is below 35 °F.
307.05 Preparation of Subgrade . Before beginning any lime treatment, the subgrade shall be
constructed and finished to smooth and uniform surfaces conforming to the grades and typical sections specified. Variation from the subgrade plane elevations specified shall not be more than plus or minus 0.1 foot. The subgrade shall also be proof rolled per subsection 307.07. Soft or otherwise unsuitable subgrade disclosed by proof rolling shall be over -excavated and replaced to a compacted stable state. The in -place density shall be at least 95 percent of AASHTO T 99 density within 0- 3 percent of optimum moisture content.