Division 600 Miscellaneous Construction Section 601 Structural
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601.02 DIVISION 600 MISCELLANEOUS CONSTRUCTION SECTION 601 STRUCTURAL CONCRETE DESCRIPTION 601.01 This work consists of furnishing and placing portland cement concrete in accordance with these specifications and in conformity with the lines, grades and dimensions as shown on the plans or established. This work includes preparing concrete surfaces designated in the Contract and applying an approved colored Structural Concrete Coating to them. 601.02 Classification. The classes of concrete shown in Table 601-1 shall be used when specified in the Contract. Table 601-1 CONCRETE TABLE Cementitious Material Air Required Field Water/Cementitious Concrete Content: Content: Compressive Material Ratio: Class Minimum or % Range Strength (psi) Maximum or Range Range (Total) (lbs/yd3) B 4500 at 28 days N/A 5 - 8 0.45 BZ 4000 at 28 days 610 N/A 0.45 D 4500 at 28 days 615 to 660 5 – 8 0.45 DT 4500 at 28 days 700 5 – 8 0.44 E 4500 at 28 days 520 4 – 8 0.44 G 4500 at 28 days N/A 5 – 8 0.45 H 4500 at 56 days 500 to 640 5 – 8 0.42 - 0.44 HT 4500 at 56 days 500 to 640 5 – 8 0.42 - 0.44 P 4500 at 28 days 520 4 – 8 0.44 S35 5000 at 28 days 615 to 720 5 – 8 0.42 S40 5800 at 28 days 615 to 760 5 – 8 0.40 S50 7250 at 28 days 615 to 800 5 – 8 0.38 Shotcrete 4500 at 28 days N/A 7-10 * 0.45 * Prior to pumping for wet process. Class B concrete is an air entrained concrete for general use. Class D, H or P concrete may be substituted for Class B concrete. Additional requirements are: The coarse aggregate shall have a nominal maximum size of 1½ inches or smaller. Class BZ concrete is concrete for drilled shafts. Additional requirements are: Entrained air is not required unless specified in the Contract. When entrained air is specified in the Contract, the air content shall be 5 to 8 percent. Slump shall be a minimum of 6 inches and a maximum of 9 inches. The coarse aggregate size shall be AASHTO M43 size #8 unless otherwise approved by the Engineer. A minimum of 6 inches slump shall be maintained during the anticipated pour period. The use of retarders and mid-range water reducers is allowed to extend the slump life of the concrete. When the Contractor elects to use SCC, the slump requirement for Class BZ Concrete does not apply. Class D concrete is a dense medium strength structural concrete. Class H may be substituted for Class D concrete. Additional requirements are: An approved water reducing admixture shall be incorporated in the mix. The concrete mix shall be made with AASHTO M 43 sizes No. 57, No. 6, or No. 67 coarse aggregate. When placed in a bridge deck, the concrete mix shall consist of a minimum 55 percent AASHTO M 43 size No. 67 coarse aggregate by weight of total aggregate. 6-1 601.02 Class DT concrete may be used for deck resurfacing and repairs. Class HT may be substituted for Class DT concrete. Additional requirements are: An approved water reducing admixture shall be incorporated into the mix. The concrete mix shall consist of a minimum 50 percent AASHTO M 43 size No. 7 or No. 8 coarse aggregate by weight of total aggregate. Class E concrete is used for fast track pavements needing early strength in order to open a pavement to service soon after placement. Class E concrete shall meet the requirements of Class P concrete. ASTM C150 Type III or ASTM C1157 Type HE cement may be used. Accelerating admixtures may be used. Class G concrete is a low shrinkage macro fiber-reinforced structural concrete. Class G concrete may be substituted for Class B or Class D concrete. Additional requirements are: (1) The concrete shall include a minimum of 4 pounds per cubic yard of Macro Fiber-Reinforcement. (2) Shrinkage reducing admixtures may be incorporated into the mix. (3) The unrestrained shrinkage shall be less than 0.030 percent when tested by CP-L 4103. (4) The permeability of the mix shall not exceed 2,500 coulombs at an age of not more than 56 days when tested in accordance with ASTM C1202. (5) The mix may contain more than 30 percent fly ash by weight of the total cementitious material. (6) The mix may use an optimized gradation. The mix shall have a nominal maximum aggregate size of ¾ inch if an optimized gradation is not used. (7) An expansive cement additive may be added to an ASTM C150 Type I/II cement and fly ash to produce an ASTM C845 Type K cement. Approximately 15 to 20 percent by weight of the cementitious content of the concrete will be the expansive cement additive. The proportion of the expansive cement additive will be determined by testing the cementitious material blend in accordance with ASTM C806. The blended material shall have an expansion of 0.04 to 0.10 percent at 7 days when tested in accordance with ASTM C806. When an expansive cement is used the w/cm ratio shall be 0.45 to 0.55, and the expansion of the laboratory trial mix shall be 0.05 to 0.09 percent at 7 days when tested in accordance with ASTM C878. Class H concrete is used for bare concrete bridge decks. Additional requirements are: (1) Type A or dual rated Type A and F chemical admixtures may be used. (2) Set retarding and accelerating admixtures shall not be used. These include Type B, C, D, E, and G chemical admixtures. (3) The concrete mix shall consist of a minimum of 55 percent sizes No. 57, No. 6, or No. 67 coarse aggregate by weight of total aggregate. (4) The permeability of the laboratory trial mix shall not exceed 2000 coulombs at 56 days when tested in accordance with ASTM C1202. (5) The cracking tendency of the laboratory trial mix shall not exhibit a crack before 15 days when tested in accordance with AASHTO T334. (6) Class H concrete shall contain a minimum of 20 percent pozzolan by weight of total cementitious material. (7) The sulfate exposure is Class 0 except when substituted for Class B or D concrete. Class HT concrete is used for deck resurfacing and repairs on bare concrete bridge decks. Additional requirements are: (1) Type A or dual rated Type A and F chemical admixtures may be used. (2) Set retarding and accelerating admixtures shall not be used. These include Type B, C, D, E, and G chemical admixtures. (3) The concrete mix shall consist of a minimum of 50 percent size No. 7 or No. 8 coarse aggregate by weight of total aggregate. (4) The permeability of the laboratory trial mix shall not exceed 2000 coulombs at 56 days when tested in accordance with ASTM C1202. (5) The cracking tendency of the laboratory trial mix shall not exhibit a crack before 15 days when tested in accordance AASHTO T334. (6) Class HT concrete shall contain a minimum of 20 percent pozzolan by weight of total cementitious material. (7) The sulfate exposure is Class 0. Class P concrete is used in pavements. Additional requirements are: The Required Field Flexural Strength shall be 650 psi when flexural strength acceptance is specified. The laboratory trial mix shall produce a minimum average 28 day flexural strength of 6-2 601.02 700 psi. The concrete mix shall consist of a minimum 55 percent AASHTO M 43 size No. 357 or No. 467 coarse aggregate by weight of total aggregate. If all transverse joints are doweled, the concrete mix shall consist of a minimum 55 percent AASHTO M 43 sizes No. 57, No. 6, No. 67, No. 357, or No. 467 coarse aggregate by weight of total aggregate. Class S35 concrete is a dense high strength structural concrete. Additional requirements are: An approved water reducing admixture shall be incorporated in the mix. The concrete mix shall be made with AASHTO M 43 sizes No. 57, No. 6, No. 67, No. 7 or No. 8 coarse aggregate. When placed in a bridge deck, the concrete mix shall consist of a minimum 55 percent AASHTO M 43 size No. 67 coarse aggregate by weight of total aggregate. Class S40 concrete is a dense high strength structural concrete. Additional requirements are: An approved water reducing admixture shall be incorporated in the mix. The concrete mix shall be made with AASHTO M 43 sizes No. 57, No. 6, No. 67, No. 7 or No. 8 coarse aggregate. When placed in a bridge deck, the concrete mix shall consist of a minimum 55 percent AASHTO M 43 size No. 67 coarse aggregate. Class S50 concrete is a dense high strength structural concrete. Additional requirements are: An approved water reducing admixture shall be incorporated in the mix. The concrete mix shall be made with AASHTO M 43 sizes No. 57, No. 6, No. 67, No. 7 or No. 8 coarse aggregate. When placed in a bridge deck, the concrete mix shall consist of a minimum 55 percent AASHTO M 43 size No. 67 coarse aggregate by weight of total aggregate. The laboratory trial mix shall not exhibit a crack before 15 days in the cracking tendency test (AASHTO T334). Deviations from the Standard Class B, Class BZ, Class D, Class DT, Class E, and Class P concrete may be made under the following conditions: (1) The minimum cement content may be reduced from that specified in Table 601-1 if lab test results show that the permeability of the mix does not exceed 2,500 Coulombs at an age of not more than 56 days as determined by ASTM C1202.The maximum cement content may be increased from that specified in Table 601-1 if lab test results show that the unrestrained shrinkage is less than 0.050 percent when tested by CP-L 4103.