02690.00 1136 Section 02690 - PCC Aggregates
Description
02690.00Scope - This Section includes the requirements for C oarse and Fine Aggregates for
portland cement concrete.
02690.01Definitions :
Coating - Foreign or deleterious substances found adhering to the A ggregate particles.
Detrimental Materials - Materials that adversely affect concrete, including but not limited to C lay, shale, mica, Silt, bark, alkali, sticks, organic matter, soft and flaky particles.
Nominal Maximum Size Of Aggregate - One sieve larger than the first sieve that retains more than 10 percent of the material using an Agency specified set of sieves based on cumulative percent retained. Where large gaps in specification sieves exist, intermediate sieves may be inserted to determine nominal maximum size.
Materials
02690.10Mate rials - PCC Aggregates shall consist of natural or crushed R ock that is hard, strong,
durable and free from adherent C oatings or other Detrimental Materials.
Produce, handle and store the Aggregates in a way that will maintain passing material properties and avoid introducing deleterious materials or segregation prior to its use in portland cement concrete.
02690.11Alternate Grading - The Contractor may request appro val to produce C oarse and Fine
Aggregates in sizes other than those stated in 02690.20 and 02690.30. The request shall be in writing, and shall state the proposed target value and specified tolerances for each of the individual sieve sizes of the materials the Contractor proposes to produce.
02690.12Acceptance of Aggregate - Acceptance of A ggregate will be according to Section 00165
and based on the Contractor's quality control testing, if verified, according to Section 00165.
quality lev el for each sieve size calculated according to 00165.40 is equal to or greater than the quality level in Table 00165-2 for a PF of 1.00. Each required sample represents a sublot. When the quality level in Table 00165-2 yields a PF of less than 1.00 for any constituent, the material is non-specification.
non-specification A ggregate gradation will be rejected by the Engineer unless non specification material is removed from the stockpile. Do not add additional material to the stockpile until enough non-specification material is removed so that the quality level for each constituent is equal to or greater than t he quality level in Table 00165-2 for a 1.00 PF.
Reprocessing of non -conforming material and the testing required for acceptance will be at no additional cost to the Agency. Acceptance of reprocessed material will be based on passing test results or accepted visually by the Engineer.
02690.20 1137 02690.20 Coarse Aggregate :
Test Method Percent Test ODOT AASHTO (by Weight)
Lightweight Pieces – T 113 1.0 Material passing No. 200 sieve – T 27 / T 11 1.0 Wood Particles TM 225 – 0.05
sulfate salt, according to AASHTO T 104. The weighted percentage loss shall not exceed 12 percent by weight.
Test Method Test ODOT AASHTO Requirements
Abrasion – T 96 30.0% Max. Oregon Air Aggregate Degradation: Passing No. 20 sieve TM 208 – 30.0% Max. Sediment Height TM 208 – 3.0" Max.
particles retained on the 3/8 inch, 1/2 inch, 3/4 inch, 1 inch, and 1 1/2 inch sieves, as determined by AASHTO T 335.
weight of the material retained on the No. 4 sieve when tested according to ODOT TM 229 with the proportional caliper device set at a ratio of 5: 1.
analysis shall be according to AASHTO T 27 and AASHTO T 11. Provide Aggregates meeting the gradation requirements of Table 02690-1 for structural concrete. Provide a CAgT to perform sampling and testing when required.
02690.30 1138 Table 02690-1 Gradation of Coarse Aggregates Percent passing (by Weight)
02690.30Fine Aggregates :
the same pile. Do not use alternately in the same class of mix, without prior approval.
Test Method Percent Test (AASHTO) (by Weight)
Lightweight Pieces T 113 2.0% Material passing No. 200 s ieve T 27 / T 11 3.0%
according to AASHTO T 104. The weighted percentage loss shall not exceed 10 percent by weight.
organic im purities.
a Sand equivalent of not less than 75 .
according to AASHTO T 27 and AASHTO T 11. Provide Aggregates meeting the gradation requirements of Table 02690- 5 for structural concrete. Provide a CAgT to perform sampling and testing when required.
02690.30 1139 Table 02690 -5 Gradation of Fine Aggregate *
Sieve Size Percent Passing (by Weight) 3/8" 100 No. 4 90 - 100 No. 8 70 - 100 No. 16 50 - 85 No. 30 25 - 60 No. 50 5 - 30 No. 100 0 - 10 No. 200 **
* Determine the fineness modulus according to AASHTO T 27 and AASHTO T 11. Maintain the Fine Aggregate fineness modulus within plus or minus 0.20 from the fineness modulus used in the Contractor's mix design. Fine Aggregates in which the fineness modulus varies by more than 0.20 from the mix design target shall not be incorporated until an assessment is done to determine whether an adjustment in the Aggregate proportions is necessary. Proportion changes must be performed by a CCT according to the provisions of ACI 211. Submit analysis of FM and mix design adjustments to the Engineer for approval.
** See 02690.30(b). Do not evaluate material passing No. 200 sieve according to 00165.40.