SUPPLEMENTARY CEMENTITIOUS MATERIALS 702.02 655 SECTION 702
702.01 Fly Ash
A.General Fly ash . A very fine, fluid material with pozzolanic properties and possibly some cementitious properties that is a by -product gathered by dust collection sys tems during the coal burning process at coal fired power plants. Substitution of a portion of the cement in portland cement concrete (PCC) with fly ash in accordance with Subsection 701.01, “Mix Design and Proportioning is allowed.” Use of fly ash to stabilize or modify soils in accordance with OHD L-50 and OHD L-51 is allowed . Provide fly ash for PCC from one source (power plant) and soil stabilization or modification fly ash from one source. Protect fly ash from cont amination and dampness. The Resident Engineer will not accept lumpy, contaminated, or partially set fly ash.
B.Requirements for Portland Cement Concrete Use Provide fly ash for PCC in accordance with AASHTO M 295, Class C or Class F.
C.Requirements for Soil Use Provide fly ash for soil stabilization or modification in accordance with AASHTO M 295, Class C.
702.02 Slag Cement
A.General Slag cement . A glassy granular, non -metallic by -product of iron production that is ground to various degrees of fineness and consists of silicates and aluminosilicates of calcium and other bases. Substitution of a portion of the cement in PCC with slag cement is allowed if in accordance with Subsection 701.01, “MIX DESIGN AND PROPORTIONING.” Provide slage cement from one source only (plant) in the PCC . Protect slag cement from contamination and dampness. The Resident Engineer will not accept lumpy, contaminated, or partially set slag cement .
B.Requirements Provide slag cemen t in accordance with AASHTO M 302, Grade 100 or Grade 120.
702.04 Supplementary Cementitious Materials
656 702.03 CEMENT KILN DUST
A.General Cement kiln dust (CKD). A very fine by -product of portland cement manufacturing, with particle sizes between 6 microns and 100 microns, that is gathered by kiln d ust collection systems during the cement clinker manufacturing process and consists of a particulate mixture of partially calcined and untreated raw feed, clinker dust, and fuel ash, enriched with alkali sulfates, halides, and other volatiles. Use of CKD t o stabilize or modify soils in accordance with OHD L-50 or OHD L-51 is allowed. Provide CKD from one source (plant). Protect CKD from contamination and dampness. The Resident Engineer will not accept lumpy, contaminated, or partially set CKD.
B.Requirem ents Test CKD in accordance with AASHTO T 105 to determine the total calcium oxide (CaO), the alkali equivalent {(0.658×K 2O)+(Na 2O)}, the total sulfates (SO 3), and the loss on ignition. Refer to Table 702:1 for the chemical content limits based on average values of samples from the plant the month before shipment. Table 702:1 Chemical Content of CKD Property Limits, % Total calcium oxide ≥35 Alkali equivalent ≤8 Total sulfates ≤10 Loss on ignition ≤30
702.04 Silica Fume
A.General Silica fume. A very fine pozzolanic by -product of the production of elemental silicon and ferrosilicon alloys, composed mostly of amorphous silica produced by electric arc furnaces; also known as condensed silica fume and microsilica. Substitution of a portion of the cem ent in PCC with silica fume in accordance with Subsection 701.01, “Mix Design and Proportioning ,” is allowed. Provide silica from one source (plant). Protect silica fume from contamination and dampness. If storing in a liquid state, continually mix during storage. The Resident Engineer will not accept lumpy, contaminated, or partially set silica fume.
B.Requirements Provide silica fume in accordance with of ASTM C 1240. BASES AND MISCELLANEOUS AGGREGATES 703.01 657 SECTION 703 BASES AND MISCELLANEOUS AGGREGATES
703.01 Aggregate for Aggreg Ate Base
A.General Requirements Provide aggregate base course material consisting of a mixture of coarse and fine graded aggregate that is free of vegetation and other deleterious materials. Coarse aggregate is the material retained on a No. 10 [2.00 mm] sieve. Provide coarse aggregate consisting of the following durable particles or fragments: Gravel, Stone, Disintegrated granite, Crushed concrete, or A combination of these. Provide fine aggregate made of sand, stone dust, or other inert, finely -divided mineral. Ensure at least 40 percent of the completed Type A or Type B mixture retained on the No. 4 [4.75 mm] sieve contains uniformly graded, mechanically crushed part icles with at least one fractured face. Ensure 100 percent of the completed Type C or Type D mixture retained on the No. 4 [4.75 mm] sieve contains uniformly graded, mechanically crushed particles with at least two fractured faces. Ensure the completed T ype C mixture contains no more than 15 percent natural sand.
B.Physical Properties Ensure the coarse aggregate retained on the ⅜ in [9.5 mm] sieve of the completed mixture has no more than 50 percent wear in accordance with the Los Angeles Abrasion Test i n accordance with AASHTO T 96. Ensure the aggregate has an Aggregate Durability Index of at least 40 in accordance with AASHTO T 210.
C.Gradation and Other Requirements Sample the uniform mixture from the project site before compacting. Ensure samples a re in accordance with Table 703:1 for Gradation, Plasticity Index, and Liquid Limit for the provided aggregate base type.
Source: Oklahoma Standard Specifications for Highway Construction, 2019 Edition. Pages 669–670 of 935.