823SOIL AGGREGATE MATERIALS

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Chert-sand shall meet the same general requirements provided in the Subarticle 820.02(c) for chert, except that it is an artificial mixture composed of chert and sand.

Float gravel shall be a varying stream deposit of worn and weathered coarse aggregate containing varying amounts of sand and soil. Oversized rock and boulders are frequently encountered and require reduction in size if used or elimination from the desired material. If provided by the plans, sand or binder soil shall be combined to provide for an artificial mixture.

Industrial waste shall be a mixture of foundry sand and fragments of slag or other materials of a durable nature. This is a waste material occurring as a result of processing iron and steel, and due to chemical actions therein, the stockpile must be approved by the Materials and Tests Engineer before it may be used.

Red Dog-sand is an artificial mixture of red dog and sand. Red dog (or red ash) is a burned waste material from mining or industrial operations, and in general is a fragmentary, tile-like material with varying amounts of binder and fines which will not be permitted unless specified on the plans or in the proposal.

Soft sand rock - any aggregate shall be an artificial mixture consisting of soft sand rock as defined by Subarticle 821.02(e) combined with (1) any aggregate or (2) other base materials which in general is predominantly coarse aggregate.

Stone, gravel, and slag aggregate shall meet the general requirements provided by Articles 801.03,

801.04, and 801.05 respectively. This classification is an artificial mixture of stone, gravel, or slag

aggregate and (1) binder soil, or (2) clay gravel, chert, float gravel, or other natural soil-aggregate material.

Limerock shall be crushed or processed as a part of the mining operations. Limerock shall not have chert or other deleterious substances. Limerock shall have a carbonate (calcium or magnesium) content of at least 90 %. At least 97 % (by weight) of the material shall pass a 3.5 inch sieve and the material shall be graded uniformly down to dust. The fine material shall consist entirely of dust of fracture. The liquid limit shall not exceed 35 and the crushed limerock material shall be non-plastic. Limerock shall have an LBR of at least 100 % according to ALDOT-427 "Procedure for Limerock Bearing Ratio." Producers of Limerock shall participate in ALDOT-249, "Procedure for Acceptance of Fine and Coarse Aggregates." PROCESSED REEF SHELL BASE MATERIALS 693

823.03Specific Requirements

GENERAL COMPOSITION Sieve Requirements Percentage Passing By Weight {Mass} TYPE A B C 2.5 inches {63 mm} 100 100 2 inches {50 mm} 100 85-100 85-100 1 inch {25.0 mm} 85-100 50-100 50-100 3/4 inch {19.0 mm} 35-95 No. 4 {4.75 mm} 50-85 30-75 25-58* No. 8 {2.36 mm} 35-75 25-70 22-50 No. 10 {2.00 mm} 30-74 22-69 20-49 No 40 {425 µm} 12-68 6-67 6-48 No. 200 {75 µm} 4-28 3-29 3-23 Clay 2-15 2-14 2-12 Liquid Limit (LL) 26 Max. 26 Max. 26 Max. Plasticity Index (PI) 6 Max. 6 Max. 6 Max. * Retained portion must contain a minimum of 25% crushed particles. 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 base will meet the above requirements. PROCESSED REEF SHELL BASE MATERIALS

824.01Description

Processed Reef Shell Base for the purpose of these Specifications is classified as a composite base course material which contains a large percentage of Processed Reef Shell blended with portions of Selected Soil, Granular Soil, Soil Aggregate, or other approved materials.

824.02General Requirements

Processed Reef Shell furnished for use shall comply with the requirements of Article 827.02 and, when combined with other material, shall produce the material complying with the designated type noted in the specific requirements provided in Article 824.03. Gradation may be obtained by the proper blending of local or other commercial materials and approximately 40% of reef shell by weight {mass} for Type A and approximately 60% reef shell by weight {mass} for Type B. Special note is made of the fact that, should the gradation run on the extreme fine or coarse side, difficulty can be expected in obtaining the modified proctor density.