816.01 General
Provide material consisting of sound, durable particles of gravel or sand which may include limited quantities of fine soil particles as binding material. Use material that is free of any deleterious material or organic material.
816.02 Miscellaneous Aggregates
Supply aggregate that meets the requirements of Table 816- 01. Table 816 -01 Miscellaneous Aggregates Sieve Size Or Testing Method Aggregate Class 2 3 3M 4 5 7 8 13 Percent Passing or Testing Requirement 3 inch 100 1-1/2 inch 100 1 inch 100 100 100 100 3/4 inch 100 80-100 80-100 100 90-100 95-100 70-100 1/2 inch 85-100 3/8 inch 50-95 60-90 No. 4 35-85 35-85 35-85 35-70 15-25 35-80 38-75 No. 8 2-10 22-62 No. 10 0-15 No. 30 0-4 20-50 20-50 10-50 16-40 12-45 No. 200 0-15 4-10 7-17 4-10 0-3 7-15 ND T 113, Shale (max %) 12.0% 12.0% 15.0% 12.0% 8.0% 20.0% 12.0% AASHTO T 96, L.A. Abrasion (max %) 50% 50% 40% 50% NDDOT 4, Fractured Faces1 10% 10% 85% 10% 1 Minimum weight percentage allowable for the portion of the aggregate retained on a No. 4 sieve having at least 1 fractured face for Classes 4, 5, and 13 and at least 2 fractured faces for Class 7. The maximum Plasticity Index (PI) for class 5 aggregate is based on the material gradation and is derived from the following formula: Max PI = 10 − (percent passing the No. 40 sieve ÷ 10) The PI of the material will be determined in accordance with test ND T 90, “Determining the Plastic Limit and Plasticity Index of Soils”.
816.03 Aggregates for Blotter and Seal Coats
Supply aggregate that meets the requirements of Table 816- 02. 417 Table 816 -02 Aggregates for Blotter and Seal coats Sieve Size Or Testing Method Aggregate Class 41 41M 42 43 44 45 Percent Passing or Testing Requirement 5/8 inch 100 3/8 inch 100 100 No. 4 20-70 90-100 85-100 No. 8 0-17 2-20 0-17 No. 16 45-80 No. 50 10-30 No. 200 0-1.5 0-5 0-2 0-20 0-3 ND T 113, Shale (max %) 8.0% 3.0% AASHTO T 96, L.A. Abrasion (max %) 40% NDDOT 4, Fractured Faces1 50% 1 Minimum weight percentage allowable for the portion of the aggregate retained on a No. 4 sieve having at least 1 fractured face for Class 41M.
816.04 Aggregate for Micro Surfacing
A.General. Use aggregate that is manufactured crushed stone such as granite, slag, limestone, or other high quality aggregate or combination thereof. Before stockpiling aggregate, perform the tests specified in Table 816-03. Table 816 -03 Test Test Method Requirement Soundness of Aggregates by Use of Sodium Sulfate AASHTO T 104 15% Max Resistance to Degradation of Small -Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine1 AASHTO T 96 30% Max Deleterious Substances ND T 176 60 or Higher 1 Perform the AASHTO T 96 test on the parent aggregate
B.Mix Design. Develop a mix design using aggregate that meets the requirements of Table 816-04. Establish mix design target values for each sieve and submit the mix design before beginning placement operations. 418 Table 816 -04 Aggregate Gradation for Development of Mix D esign SIEVE SIZE TYPE II %PASSING TYPE III %PASSING 3/8” 100 100 #4 90 – 100 70 – 90 #8 65 – 90 45 – 70 #16 45 – 70 28 – 50 #30 30 – 50 19 – 34 #50 18 – 30 12 – 25 #100 10 – 21 7 – 18 #200 5 – 15 5 – 15
C.Stockpile Tolerances. The mix design target values will be used for acceptance of material. Gradation tests may vary from the mix design target values based on the stockpile tolerance shown in Table 816-
05.The percent passing each sieve for gradation tests may not fall outside the gradation limits specified in Table 816-04. Table 816 -05 SIEVE SIZE STOCKPILE TOLERANCE 3/8” - #4 + 5% #8 +5% #16 +5% #30 +5% #50 +4% #100 +3% #200 +2%
D.Acceptance.
1.Stockpile Testing. Perform a gradation test in accordance with ND T 11 and ND T 27 for every 500 tons of material produced and placed in the stockpile. Also perform test ND T 176 when performing gradation tests. Submit the test results to the Engineer. The Engineer will perform acceptance testing. If the result of the Engineer’s testing lead to rejection of the stockpile, additional material may be blended with the stockpiled material so that the stockpile meets the requirements. The Engineer will resample and retest for both gradation and deleterious substances to determine if the stockpiled material will be accepted. If choosing to blend additional material into the stockpile, use additional material that meets the requirements of Table 816-06. After blending, develop and submit a new mix design. 419 2. Gradation. The Engineer will obtain 5 independent samples from the stockpile and perform a gradation analysis in accordance with ND T 11 and ND T 27. If the average gradation for each sieve is within the stockpile tolerance of the mix design target values, the Engineer will accept the material. If the stockpile is rejected, additional material may be blended with the stockpiled material to obtain the required gradation. The Engineer will resample and retest to determine if the stockpiled material will be accepted. If choosing to blend additional material into the stockpile, use additional material that meets the requirements of Table 816-03. After blending, develop and submit a new mix design.
3.Deleterious Substances. The Engineer will determine the amount of deleterious substances in the aggregate using the same samples obtained in Section 816.04 D.2, “Gradation” . If the average of the test results is 60 or higher, the Engineer will accept the material.
816.05 Aggregate for Slurry Seal
A.General. Use aggregate that is manufactured crushed stone such as granite, slag, limestone, or other high quality aggregate or combination thereof. Use aggregate with 100 percent of the parent aggregate larger than the largest stone in the specified gradation. Before stockpiling aggregate, perform the tests specified in Table 816-06. Table 816 -06 Test Test Method Requirement Soundness of Aggregates by Use of Sodium Sulfate AASHTO T 104 15% Max Resistance to Degradation of Small -Size Coarse Aggregate by Abrasion and Impact in the Los Angeles Machine1 AASHTO T 96 35% Max Deleterious Substances ND T 176 60 or Higher 1 Perform the AASHTO T 96 test on the parent aggregate
B.Mix Design. Develop a mix design using aggregate that meets the requirements of Table 816-07. Establish mix design target values for each sieve and submit the mix design before beginning placement operations. 420 Table 816 -07 Aggregate Gradation for Development of Mix D esign SIEVE SIZE TYPE II %PASSING TYPE III %PASSING 3/8” 100 100 #4 90 – 100 70 – 90 #8 65 – 90 45 – 70 #16 45 – 70 28 – 50 #30 30 – 50 19 – 34 #50 18 – 30 12 – 25 #100 10 – 21 7 – 18 #200 5 – 15 5 – 15
C.Stockpile Tolerances. The mix design target values will be used for acceptance of material. Gradation tests may vary from the mix design target values based on the stockpile tolerance shown in Table 816-
08.The percent passing each sieve for gradation tests may not fall outside the gradation limits specified in Table 816-07. Table 816 -08 SIEVE SIZE STOCKPILE TOLERANCE 3/8” - #4 + 5% #8 +5% #16 +5% #30 +5% #50 +4% #100 +3% #200 +2%
D.Acceptance.
1.Stockpile Testing. Perform a gradation test in accordance with ND T 11 and ND T 27 for every 500 tons of material produced and placed in the stockpile. Also perform test ND T 176 when performing gradation tests. Submit the test results to the Engineer. The Engineer will perform acceptance testing. If the result of the Engineer’s testing lead to rejection of the stockpile, additional material may be blended with the stockpiled material so that the stockpile meets the requirements. The Engineer will resample and retest for both gradation and deleterious substances to determine if the stockpiled material will be accepted. If choosing to blend additional material into the stockpile, use additional material that meets the requirements of Table 816-06. After blending, develop and submit a new mix design. 421 2. Gradation. The Engineer will obtain 5 independent samples from the stockpile and perform a gradation analysis in accordance with ND T 11 and ND T 27. If the average gradation for each sieve is within the stockpile tolerance of the mix design target values, the Engineer will accept the material.
3.Deleterious Substances. The Engineer will determine the amount of deleterious substances in the aggregate using the same samples obtained in Secti on 816.05 D.2, “Gradation” . If the average of the test results is 60 or higher, the Engineer will accept the material. Section 817 422 SECTION 817 SALVAGED BASE COURSE
817.01 Salvaged Base Course
A.General. Salvage base course must include a minimum of 30 percent of one or more of the following materials: − existing bituminous material; − existing concrete material; − stockpiled bituminous material; and − stockpiled concrete material. The remaining portion of the salvage base material may be composed of the following materials: − virgin aggregate; − existing aggregate base; − existing bituminous material; − stockpiled bituminous material; − existing concrete material; and − stockpiled concrete material. The total amount of bituminous material in salvaged base course is limited as specified in Section 817.01 D, “ Salvage Base Course Containing Bituminous Material ”. If seeking to substitute virgin aggregate in lieu of sal vaged base course, submit a written request, including a detailed justification. If the request is approved, the virgin material must meet the requirement of class 5 aggregate as specified in Aggregates” . If the quantity of removed material exceeds the amount of salvaged base course needed for the work, dispose of the excess material in accordance with Section 107.17, “Removed Material” . Produce salvaged base that is free of reinforcing steel, soil, scoria, and other deleterious materials.
B.Salvaged Base Course Gradation. Sieve Size Percent Passing 1-1/2 inch 100 1 inch 90 - 100 No. 4 35 - 85 No. 30 16 - 50 No. 200 0.0 - 12.0
C.Virgin Aggregate for Blending with Salvage Base Course. Provide virgin aggregate meeting the requirements of Class 5 aggregate in Section 816, “Aggregates” when blending with salvage base course.
Source: North Dakota Standard Specifications for Road and Bridge Construction, 2022 Edition. Pages 451–456 of 550.