301.01 Description. This item shall consist of treating the
existing subgrade with water and lime according to these specifications and in substantial conformity with t he lines, grades, compacted thickness, and cross section shown on the plans.
301.02 Composition. The mixture shall be composed of the soil
in the existing subgrade, lime, and water. The mix ture shall contain not more than 8% by weight of lime. At least 30 da ys before the beginning of lime treatment, adequate quantities of soil and lime shall be supplied to the Materials Division for det ermination of lime requirements. The Engineer will specify, based on laboratory tests, the exact percentage of lime to be used. The type of lime used shall be either quicklime or hydrated lime as shown in the Contract.
301.03 Materials. The materials shall comply with the following
requirements:
a.Water. All water used in mixing shall be clean and free from injurious amounts of oil, salt, or other deleteriou s substances, and shall be free of vegetable matter or other foreign materials.
b.Lime. The lime shall comply with AASHTO M 216.
c.Soil. The soil shall be the soil in the existing subgra de.
301.04 Construction Requirements. (a) Preparation o f
Subgrade. Before beginning the lime treatment, the subgrade shall be shaped to the required grade and section and com pacted to sufficient density to prevent rutting under normal operation of construction equipment. Soft areas shall be correc ted to provide uniform stability before lime application. Any mat erial in temporary cross roads, bridge approaches, or other areas that extends above the elevation of the proposed subgrad e shall be removed and disposed of, as directed.
b.Preparation of Soil. The proposed roadbed shall be scarified to the depth and width indicated on the plans for t he subgrade treatment. The scarified material shall be partial ly pulverized. The depth of scarification shall be carefully controlle d and operations 188 DIVISION 300 BASES AND GRANULAR SURFACES
Source: , Edition.