820SELECTED MATERIALS FOR BASES

689

SELECTED MATERIALS FOR BASES

820.01Description

Selected materials for the purpose of these specifications shall be of the kind and general character of sand-clay, chert, clay-gravel, sand, local stone, stone screenings, etc., or combinations thereof, with or without commercial aggregate meeting the requirements noted in this Section.

820.02General Requirements

The material shall meet the general requirements for the respective material noted in this Article and the special and specific requirements noted in Article 820.03. The following terms are defined for general use. Artificial Mixture . The term "Artificial Mixture" is defined as a mixture, resulting from combining as indicated on the plans or as directed, of two or more base course materials, including binder soils suitable for the purpose intended and sands of the same or different kind generally from separate sources. Coarse Aggregate and Binder Soil (Binder). The coarse aggregate for base courses shall be all material retained on the No. 8 {2.36 mm} sieve; binder shall be all materials passing the No. 8 {2.36 mm} sieve. Blends. Blends shall be an artificial mixture of (1) two or more materials of the kind and/or character described in this Section or similar materials; (2) one or more soils plus stabilizer aggregate or either local stone, commercial coarse aggregate meeting the provisions of Section 801 with size number designated on the plans, or processed reef shell meeting provisions of Section 827.

Sand clay shall be a natural material or artificial mixture, consisting largely of a mixture of sand and clay in proper proportions, that occurs in natural deposits of varying depths or a blended mixture of sand and clay.

Chert shall be a metamorphic, fragmentary, flint or silica formation interspersed with varying quantity and quality of clay binder. Chert in its natural formation may require blasting to facilitate loading and manipulation.

Clay gravel shall be composed of gravel and sand with clay binder. The coarse aggregate (gravel) shall be clean, hard, tough, durable, and reasonably free from thin, elongated, soft, or laminated pieces. The binder, consisting of material passing the No. 8 {2.36 mm} sieve, shall be a good grade of sand clay or other approved material. Clay gravel in its natural formation may require blasting to facilitate loading and manipulation.

Local sand shall consist of grains of hard, sound material, predominantly quartz or other hard, durable rock, including friable, loosely bound deposits of sandstone conglomerate normally found in natural deposits in the project vicinity.

Local sand-gravel shall be hard, sound, durable rock, including friable, loosely bound sand-stone conglomerate, with varying amounts of coarse aggregate and sand normally found in natural deposits in the project vicinity. The coarse aggregate and the sand shall be free from a coating of injurious material, lumps of clay, loam, organic matter, or other foreign material. If necessary, gradation and/or other requirements will be provided in the plans and/or proposal form.

Approved local source-run stone shall consist of tough, durable fragments and sand, clay, or other binder type materials. If necessary, gradation and/or other requirements will be provided in the plans or proposal. GRANULAR SOIL MATERIALS 690

Commercial aggregates shall meet the appropriate requirements of Sections 801 and 802.

Stone screenings shall consist of crushed stone fragments, all passing the No. 4 {4.75 mm} sieve with the fines down to and including dust, but not more than 30 percent by weight {mass}, passing the No. 100 {150 µm} sieve. The stone shall meet the general requirements of Section 801.

Pond ash shall consist of a combination of bottom ash and fly ash produced as a by-product of burning coal.

820.03Specific Requirements

General COMPOSITION Sieve Requirements Percentage Passing By Weight {Mass} TYPE A A-1 B B-1 C* 3 inch {75 mm} 100 100 100 100 100 No. 8 {2.36 mm} 60-100 42-100 22-75 20-70 20-50 No. 200 {75 µm} 7-45 5-45 3-38 3-46 3-35 Liquid Limit (LL) 28 Max. 35 Max. 28 Max. 35 Max. 45 Max. Plasticity Index (PI) 8 Max. 15 Max. 8 Max. 15 Max. 20 Max. * CBR of 40 + with swell of less than 5%

Material placed on the road found not meeting the above requirements may in lieu of removal and replacement be stabilized with approved materials in such proportions that the finished layer will meet the above specified requirements. GRANULAR SOIL MATERIALS

821.01Description

Granular Soil for the purpose of these Specifications shall be of the kind and general character of sand-clay, topsoil, sand, soft sand rock, etc., or combinations thereof meeting the requirements noted in this Section.

821.02General Requirements

The material shall meet the general requirements for the respective material noted in this Article and the specific requirements noted in Article 821.03. Reference is made to Subarticle 820.02(a) for definition of terms for coarse aggregate, binder, artificial mixture, and blends.

See Subarticle 820.02(b).

Topsoil base material shall consist of a natural material or artificial mixture, sometimes pebbly in character, that occurs in surface deposits of limited depth and in general on elevated areas.

Foundry sand shall be a waste material consisting of burned sand with or without slag fragments. In general, this material is waste or by-product material from foundry operations.

Soft sand rock shall be a friable natural material, generally sandy in character and occurring as a partially disintegrated sandstone with occasional hard strata, in sub surface formations of varying thickness and in general on elevated areas. Blasting is usually required to facilitate loading with power shovels. Pulverizing by use of rollers, tractors, or other equipment is usually necessary.