PART I DETERMINING DELETERIOUS MATERIAL IN COARSE AGGREGATES

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1 Test Procedure for DETERMINING DELETERIOUS MATERIAL AND DECANTATION TEST FOR COARSE AGGREGATES (BITUMINOUS MIXTURES) Texas Department of Transportation TxDOT Designation: Tex-217-F Effective Date: October SCOPE 1.1 Use Part I to determine the percent by weight of deleterious material in coarse aggregate. 1.2 Use Part II to determine the percent by weight of detrimental fine dust, clay-like particles, and silt present as a coating in coarse aggregate. 1.3 Use Part III to determine the percent by weight of deleterious material contained in processed recycled asphalt shingles. 1.4 The values given in parentheses (if provided) are not standard and may not be exact mathematical conversions. Use each system of units separately. Combining values from the two systems may result in nonconformance with the standard. PART I DETERMINING DELETERIOUS MATERIAL IN COARSE AGGREGATES 2. SCOPE 2.1 Use this procedure to determine the percent by weight of deleterious material in coarse aggregate. 3. APPARATUS 3.1 Balance, class G2 in accordance with Tex-901-K, with a minimum capacity of 4000 g. 3.2 Heating oven, capable of attaining a temperature of at least 200 ± 5 F (93 ± 3 C). 3.3 Sample splitter, quartering cloth, quartering machine, or shovel and a smooth surface. CONSTRUCTION DIVISION 1 8 EFFECTIVE DATE: OCTOBER 2011

2 3.4 Standard U. S. sieves, in accordance with Tex-907-K, in the following sizes: 3/8 in. (9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm). 3.5 Dishpan, or similar container. 3.6 Pans, scoops, trowels, and other normal laboratory supplies and equipment. 4. PROCEDURE 4.1 Obtain a representative sample of aggregate for testing, in accordance with Tex-221-F. Note 1 Select samples of crushed limestone rock asphalt from the processing plant before to the addition of the flux oil. 4.2 Oven-dry the aggregate to a constant weight at a minimum temperature of 200 F (93 C). Oven-dry the limestone rock asphalt aggregates, when used, to a constant weight at a maximum temperature of 140 F (60 C). 4.3 Remove the sample from the oven and allow to cool to room temperature. 4.4 Obtain a minimum laboratory size sample of 2000 g using one of the following methods: Sample splitter Quartering cloth Quartering machine Mix on a smooth clean surface with a large flat scoop or shovel until blended, and quarter with a straight edge. Note 2 When testing aggregates from the hot bins, the sample should consist of aggregates combined in the same proportions used in the mixture being produced. 4.5 Sieve the dried test sample over the No. 4 (4.75 mm) sieve in such a manner as to avoid breaking up any clay or loam lumps that may be present. Test the material retained on the No. 8 (2.36 mm) sieve for compliance with the deleterious material requirements if the sample contains an aggregate that predominately passes the No. 4 (4.75 mm) sieve. 4.6 Weigh the aggregate particles retained on the No. 4 (4.75 mm) sieve to the nearest 0.1 g. Weigh the aggregate particles retained on the No. 8 (2.36 mm) sieve to the nearest 0.1g, if the aggregate size requires this sieve to be used. Record the weight as W in Section Discard the portion of material passing the No. 4 (4.75 mm) sieve. Discard the portion of material passing the No. 8 (2.36 mm) sieve, when it has been determined that this sieve is to be used. CONSTRUCTION DIVISION 2 8 EFFECTIVE DATE: OCTOBER 2011

3 4.8 Spread the aggregate sample (portion retained on the No. 4 [4.75 mm] or No. 8 [2.36 mm] sieve) out on an area of the worktable large enough to examine the individual particles carefully. 4.9 Separate and classify each type of deleterious matter from the remainder of the sample by visual inspection. Material may be wetted, or other suitable methods may be used to aid in identification Dry and weigh all objectionable material removed from the aggregate sample to the nearest 0.1 g and record the weight as D in Section CALCULATIONS 5.1 Calculate the percentage of each or a combination of deleterious materials: P D 100 W Where: P = Percentage of deleterious matter by weight D = Weight of deleterious substances, g W = Weight of total sample (retained on No. 4 [4.75 mm] or No. 8 [2.36 mm]), g. PART II DECANTATION TEST FOR COARSE AGGREGATE 6. SCOPE 6.1 Use this procedure to determine the percent by weight of fine material adhering to the coarse aggregate due to handling or contamination by silt or clay. 7. APPARATUS 7.1 Balance, class G2 in accordance with Tex-901-K, with a minimum capacity of 4000 g. 7.2 Heating oven, capable of attaining a temperature of at least 200 ±5 F (93 ±3 C). 7.3 Sample splitter, quartering cloth, quartering machine, or shovel and a smooth surface. 7.4 Mechanical sieve shaker. 7.5 Standard U. S. sieves, meeting the requirements of Tex-907-K, in the following sizes: 3/8 in. (9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) CONSTRUCTION DIVISION 3 8 EFFECTIVE DATE: OCTOBER 2011

4 No. 200 (75 m). 7.6 Dishpan or similar container. 7.7 Pans, scoops, trowels, and other normal laboratory supplies and equipment. 8. PROCEDURE 8.1 Obtain a representative sample of aggregate for testing, in accordance with Tex-221-F. Note 3 Select the sample of crushed limestone rock asphalt from the processing plant before to the addition of the flux oil. 8.2 Oven-dry the aggregate to constant weight at a minimum temperature of 200 F (93 C). Oven-dry the limestone rock asphalt aggregates, when used, to constant weight at a maximum temperature of 140 F (60 C). 8.3 Remove the sample from the oven and allow it to cool to room temperature. 8.4 Obtain a minimum laboratory size sample of 1500 g using one of the following methods: Sample splitter Quartering cloth Quartering machine Mix on a smooth clean surface with a large flat scoop or shovel until blended, and quarter with a straight edge. Note 4 When testing aggregates from the hot bins, the sample should consist of aggregates combined in the same proportions used in the mixture being produced. 8.5 Stack the 3/8 in. (9.5 mm) and No. 4 (4.75 mm) sieves on a sieve pan. 8.6 Place 1/2 the sample on the top sieve, cover the stack, and shake in the shaker for 3 min. Test the material that is retained on the No. 8 (2.36 mm) sieve for compliance with the specification requirements if the sample contains an aggregate that predominately passes the No. 4 (4.75 mm) sieve. 8.7 Remove any material other than coated particles of aggregate that will slake down during the test. Note 5 The material remaining constitutes the decantation test sample. 8.8 Remove the stack of sieves and empty each into a dry pan, discarding the material passing the No. 4 (4.75 mm) sieve. Discard material passing the No. 8 (2.36 mm) sieve, when using the No. 8 (2.36 mm) sieve in Section Empty all sieves into one pan of convenient size Repeat Sections 8.5 through 8.9 for the remaining material. CONSTRUCTION DIVISION 4 8 EFFECTIVE DATE: OCTOBER 2011

5 8.11 Weigh the material retained on the No. 4 (4.75 mm) sieve to the nearest 0.1 g. Weigh the material retained on the No. 8 (2.36 mm) sieve to the nearest 0.1 g, if the aggregate size requires this sieve to be used. Record the weight as B in Section Place the test sample in the dishpan, cover with water, and let sample soak for at least 12 hr Agitate the contents of the pan vigorously with the hands and immediately pour the wash water over the No. 200 (75 µm) sieve. Agitate vigorously to completely separate all particles finer than the No. 200 (75 µm) sieve from the coarse particles, and to bring the fine material into suspension so that it will be removed by decantation Repeat until the wash water is clear Return all the material retained on the No. 200 (75 µm) sieve to the washed sample Dry the washed aggregate to a constant weight, as indicated in Section Weigh the dried aggregate to the nearest estimated 0.1 g and record the weight as C in Section CALCULATIONS 9.1 Calculate the percent loss by decantation: Percent Loss B C 100 B Where: B = original dry weight, g C = dry weight after washing, g. PART III DETERMINING DELETERIOUS MATERIAL IN RECYCLED ASPHALT SHINGLES (RAS) 10. SCOPE 10.1 Use this procedure to determine the percent by weight of deleterious material in processed recycled asphalt shingles (RAS). 11. APPARATUS 11.1 Balance, class G2 in accordance with Tex-901-K, with a minimum capacity of 5000 g Drying oven, capable of attaining a temperature of at least 140 ±5 F (60 ±3 C). CONSTRUCTION DIVISION 5 8 EFFECTIVE DATE: OCTOBER 2011

6 11.3 Mechanical sieve shaker Standard U.S. sieves meeting the requirements of Tex-907-K, in the following sizes: 3/8 in. (9.5 mm) No. 4 (4.75 mm) No. 8 (2.36 mm) No. 30 (0.6 mm) Rectangular pan, at least 14 in. wide Sample splitter or quartering device Small scoop Metal collection device, a rectangular, nonferrous tray, 12 in. wide, at least 20 in. long, with walls at the two long sides and both short ends open, with a 12 in. x 2 in. magnet fixed under the tray perpendicular to the walls. See Figure 1. Figure 1 Metal Collection Device 12. PROCEDURE 12.1 Obtain a representative sample from the RAS stockpile in accordance with Tex-222-F Oven-dry the sample to constant weight at 140 ± 5 F (60 ± 3 C) Remove the sample from the oven and allow to cool to room temperature. CONSTRUCTION DIVISION 6 8 EFFECTIVE DATE: OCTOBER 2011

7 12.4 Obtain a representative test sample of 1000 g using one of the following methods: Sample splitter Quartering cloth Quartering machine Weigh the sample to the nearest 0.1 g. Record the weight as W T in Section Place a pan on the scale and tare its weight Place the metal collection device on the pan and angle one of the open ends down into the pan Tilt the metal collection device to an angle of 45 degrees or more and pour the sample over the device. Ensure the sample particles pass over the magnet before falling into the pan Gently shake the metal collection device to remove material not retained by the magnet. Remove the device from the pan and discard the metal fragments retained by the magnet Weigh the material in the pan on the tared scale to the nearest 0.1 g. Record as A in Section Save this material for future testing described in Calculate the weight of metal fragments in the sample in accordance with Section Stack the 3/8 in. (9.5 mm), the No. 4 (4.75 mm), the No. 8 (2.36 mm), and the No. 30 (0.6 mm) sieves on a sieve pan Place the sample on the top sieve, cover the stack, and shake in the shaker for approximately 10 min Discard the portion of material passing the No. 30 (0.6 mm) sieve Test the material retained on each sieve for all deleterious content including but not limited to wood, paper, plastic and felt paper Spread the portion of the sample retained on the 3/8 in. (9.5 mm) sieve out in a pan large enough to examine the individual particles carefully Separate and remove the deleterious matter from the remainder of the sample by visual inspection Weigh all objectionable material removed from the RAS sample retained on the 3/8 in. (9.5 mm) sieve to the nearest 0.1 g and record the weight as N 3/8 in Section Repeat Sections through for the material retained on the No. 4 (4.75 mm), the No. 8 (2.36 mm), and the No. 30 (0.6 mm) sieves Record these weights as N 4, N 8, and N 30 respectively in Section CONSTRUCTION DIVISION 7 8 EFFECTIVE DATE: OCTOBER 2011

8 13. CALCULATIONS 13.1 Calculate the weight of the metal fragments in the original sample: M W T A Where: M = weight of material retained by the magnet, g W T = total weight of sample, g A = weight of material not retained by the magnet, g Calculate the percent by weight of deleterious material in the sample: P M N 3 / 8 N 4 W T N 8 N Where: P = percent of deleterious matter by weight M = weight of material retained by the magnet, g N 3/8 = weight of deleterious substance retained on the 3/8 in. (9.5 mm) sieve, g N 4 = weight of deleterious substance retained on the No. 4 (4.75 mm) sieve, g N 8 = weight of deleterious substance retained on the No. 8 (2.36 mm) sieve, g N 30 = weight of deleterious substance retained on the No. 30 (0.6 mm) sieve, g. 14. REPORT FORMS 14.1 Deleterious Materials and Decantation for Coarse Aggregate 15. ARCHIVED VERSIONS 15.1 Archived versions are available. CONSTRUCTION DIVISION 8 8 EFFECTIVE DATE: OCTOBER 2011

9 DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD TXDOT DESIGNATION: TEX-236-F Test Procedure for DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD Texas Department of Transportation TxDOT Designation: Tex-236-F Effective Date: October SCOPE 1.1 Use this test method to determine the asphalt content of hot mix asphalt (HMA) paving mixtures using an ignition oven. Use the remaining aggregate for sieve analysis in accordance with Tex-200-F. 1.2 Use this test method to determine aggregate gradation and asphalt content correction factors before the start of production. The type of aggregate in the mixture may affect the ignition procedure. Establish correction factors by testing a set of samples for each mix type produced to optimize accuracy. 1.3 Use this test method to determine the asphalt content and gradation of reclaimed asphalt pavement (RAP) and recycled asphalt shingle (RAS) stockpiles. 1.4 The values given in parentheses (if provided) are not standard and may not be exact mathematical conversions. Use each system of units separately. Combining values from the two systems may result in nonconformance with the standard. 2. APPARATUS 2.1 Ignition oven, capable of: Maintaining a temperature to cause combustion with an internal balance thermally isolated from the chamber accurate to 0.1 g. The balance must be capable of weighing a 4000 g sample in addition to the sample baskets Providing an audible alarm and indicator light when the sample reaches constant weight. Note 1 The oven door must automatically lock when the test procedure begins and must remain locked until the test procedure is completed Providing initial sample weight, sample weight loss, correction factor, corrected asphalt content (percent), and test time. CONSTRUCTION DIVISION 1 7 EFFECTIVE DATE: OCTOBER 2011

10 DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD TXDOT DESIGNATION: TEX-236-F 2.2 Tempered stainless steel No. 8 (2.36 mm) mesh basket, otherwise perforated basket, or combination of baskets. The basket must incorporate a design that confines the sample during testing. 2.3 Tempered stainless steel catch pan, to fit under the basket assembly. 2.4 Oven, capable of maintaining a minimum temperature of 250 ± 5 F (121 ± 3 C). 2.5 Balance, Class G2, in accordance with Tex-901-K, with a minimum capacity of 17.6 lb. (8 kg) for weighing sample in baskets. 3. SAFETY EQUIPMENT 3.1 Safety glasses or face shield. 3.2 High temperature gloves. 3.3 Long sleeve jacket. 3.4 Heat-resistant surface, capable of withstanding heat from the sample baskets. 3.5 Protective cage, capable of surrounding the sample baskets. 4. MISCELLANEOUS EQUIPMENT 4.1 Pan for transferring samples after ignition. 4.2 Spatulas. 4.3 Bowls. 4.4 Wire brushes. 5. REPORT FORMAT 5.1 The Correction Factor Calculation Report is an automated form containing the following worksheets: Asphalt Content and Combined Aggregate Gradation (Tx236) Summary Sheet (Summary) 5.2 Use the QC/QA worksheets for the 'Ignition Oven Method' in conjunction with the HMA specification. Refer to the 'Help' tab for detailed instructions on how to use this program. CONSTRUCTION DIVISION 2 7 EFFECTIVE DATE: OCTOBER 2011

11 DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD TXDOT DESIGNATION: TEX-236-F 6. CORRECTION FACTORS 6.1 Use the Blank Weigh Up worksheet in the Mix Design Report to prepare two blank samples in the laboratory in accordance with Tex-205-F, Sections Determine the sample size for the blank samples in accordance with Tex-200-F, Table 1. Note 2 Do not add any asphalt binder or any recycled materials to the blank samples. Do not perform the ignition oven procedure with the blank samples. 6.2 Perform a washed sieve analysis on each blank sample in accordance with Tex-200-F, Part II. Note 3 Enter the individual or cumulative weight of aggregate retained on each sieve on the Asphalt Content and Combine Aggregate Gradation worksheet. 6.3 When applicable, enter the gradation of any recycled material used in the mixture design, such as RAP or RAS, in the Asphalt Content and Combined Aggregate Gradation worksheet, under the Recycled Materials Section. Use the gradation of the recycled material determined for the mixture design in accordance with Tex-204-F. Note 4 The Asphalt Content and Combined Aggregate Gradation worksheet calculates the combined gradation of the blank samples and recycled materials, when applicable. Note 5 The combined gradation, including the use of any recycled materials, must fall within the master gradation band of the specification used for the project. 6.4 Prepare a butter batch mix at the design optimum asphalt content and discard before mixing any other samples for determining correction factors. Note 6 A butter batch mix is a trial batch of asphalt and aggregate design mixture used to coat the mixing bowl and whips with asphalt. This helps prevent a loss of asphalt due to adhesion on the bare walls of the bowl or in the mixing whips to ensure an accurate asphalt content of the samples used to determine correction factors. 6.5 Use the 'Weigh Up' worksheet in the Mix Design Report to prepare six samples in the laboratory in accordance with Tex-205-F. Determine the sample size in accordance with Section 7.3. two at the design optimum asphalt content two each at ±0.5% of the design optimum asphalt content. Note 7 Add the recycled material when preparing the samples, if applicable. 6.6 Perform the ignition oven procedure as described under Section 8 with the samples prepared in Section Perform a dry gradation sieve analysis in accordance with Tex-200-F, Part I on the residual aggregate for each ignited sample from Section 6.6. Note 8 Enter the individual or cumulative weight of aggregate retained on each sieve on the Asphalt Content and Combine Aggregate Gradation worksheet. CONSTRUCTION DIVISION 3 7 EFFECTIVE DATE: OCTOBER 2011

12 DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD TXDOT DESIGNATION: TEX-236-F 6.8 Determining Asphalt Content Correction Factor: Determine the asphalt content for each ignited sample in Section 6.6 in accordance with Section Use the Asphalt Content and Combined Aggregate Gradation worksheet to subtract the measured asphalt content for each ignited sample determined in Section from the actual asphalt content. Average the six measured differences to determine the asphalt content correction factor. 6.9 Determining Aggregate Gradation Correction Factors: Use the Asphalt Content and Combined Aggregate Gradation worksheet to subtract the gradation determined in Section 6.7 (ignited samples) for each sieve size from each corresponding sieve size of the combined gradation determined in Section 6.3 (blank samples and recycled material) Average the six measured differences for each sieve size to determine the aggregate gradation correction factor for each sieve size. Report the correction factors in percent passing Use the Summary worksheet to report the asphalt content and aggregate gradation correction factors. 7. SAMPLE PREPARATION 7.1 Hot Mix Asphalt (HMA): Produce a sample in accordance with Tex-205-F or quarter a sample in accordance with Tex-222-F If the mixture is not sufficiently workable to separate with a spatula or trowel, place it in a large flat pan and warm to 250 ± 5 F (121 ± 3 C) for 30 min. Note 9 Do not heat sample for more than one hour The mixture type controls the recommended sample size, as shown in Table 1. CONSTRUCTION DIVISION 4 7 EFFECTIVE DATE: OCTOBER 2011

13 DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD TXDOT DESIGNATION: TEX-236-F Table 1 Recommended Weight of Sample Mixture Type Recommended Weight of Sample, g Type A, SP-A Type B, SP-B Type C, PFC (PG 76), SP-C, CMHB-C, SMA-C, SMA-D, SMAR-C, UTBWC-C, TBPFC (PG 76) Type D, PFC (A-R), SP-D, CMHB-F, SMA-F, UTBWC-B, TBPFC (A-R) Type F, SMAR-F, Microsurfacing, CAM, UTBWC-A Sample sizes should not be more than 400 g greater than the maximum recommended sample mass as shown in Table 1. Large samples of fine mixes tend to result in incomplete ignition of the asphalt. Note 10 When the mass of the sample exceeds the capacity of the equipment used, divide the sample into suitable increments. Appropriately combine the results for calculating the asphalt content (weighted average) Verify that the mixture contains no more than 0.2% of moisture by weight in accordance with Tex-212-F, Part II. Do not use the same sample used for moisture determination as used for asphalt content determination. 7.2 Recycled Materials Samples: Take a representative sample from the recycled material stockpile in accordance with Tex-222-F Oven-dry the sample to constant weight at 140 ± 5 F (60 ± 3 C) Quarter a test sample to the required size shown in Table Verify that the mixture contains no more than 0.2% of moisture by weight in accordance with Tex-212-F, Part II. Do not use the same sample used for moisture determination as used for asphalt content determination. Table 2 Recommended Weight of Recycled Material Sample Recycled Material Type Recommended Weight of Sample, g Reclaimed Asphalt Pavement (RAP) Recycled Asphalt Shingles (RAS) Refer to Table 1 for recommended sample weights. 2. Sample size exceeding the recommended weight above may not completely ignite the asphalt. CONSTRUCTION DIVISION 5 7 EFFECTIVE DATE: OCTOBER 2011

14 DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD TXDOT DESIGNATION: TEX-236-F 8. IGNITION OVEN PROCEDURE 8.1 Pre-heat the ignition oven according to the manufacturer s recommendations. 8.2 Determine and record the weight of the basket assembly to the nearest 0.1 g. 8.3 Place the loose mixture directly into the sample baskets. Note 11 Reheat the sample in a 250 F (121 C) oven for 30 min., if it gets cold. Do not preheat the sample baskets. 8.4 Evenly distribute the sample in the basket assembly, keeping the material away from the edges of the basket. 8.5 Weigh and record the sample and basket assembly to the nearest 0.1 g. 8.6 Calculate and record the initial weight of the sample (total weight minus the weight of the sample basket assembly) and designate as W S in Section Input W S into the ignition oven controller. Verify entry of the correct weight. 8.8 Open the chamber door and place the sample and basket assembly in the ignition oven. Note 12 Failure of the oven scale to stabilize may indicate that the sample basket assembly is contacting the oven wall. If this occurs, adjust the sample basket inside the oven. 8.9 Close the chamber door and start the test. Note 13 This should lock the oven chamber for the duration of the test Allow the test to continue until the stable light and audible stable indicator indicate the test is complete Press the start/stop button. Note 14 This should unlock the oven chamber Open the chamber door, remove the sample, and allow it to cool to room temperature (approximately 45 min.). Note 15 Do not use a fan to assist in cooling the sample to room temperature due to the possibility of losing fines Weigh the sample and basket assembly after ignition to the nearest 0.1 g Calculate and record the final weight of the sample (total weight from Section 8.13 minus the weight of the sample basket assembly) and designate this weight as W A in Section Calculate the asphalt content of the sample according to Section 9.1. Note 16 Asphalt content reported by the ignition oven may be used if proven accurate. CONSTRUCTION DIVISION 6 7 EFFECTIVE DATE: OCTOBER 2011

15 DETERMINING ASPHALT CONTENT FROM ASPHALT PAVING MIXTURES BY THE IGNITION METHOD TXDOT DESIGNATION: TEX-236-F 8.16 Empty the contents of the basket into a flat pan. Use a small wire sieve brush to ensure removal of any residual fines from the basket. Add those fines to the contents in the flat pan Use the remaining aggregate for the sieve analysis in accordance with Tex-200-F. 9. CALCULATIONS 9.1 Calculate the asphalt binder content of the sample: WS WA AC % *100 WS Where: AC% = measured asphalt content W A = total weight of aggregate remaining after ignition, g W S = total weight of the HMA sample prior to ignition, g. 10. ARCHIVED VERSIONS 10.1 Archived versions are available. CONSTRUCTION DIVISION 7 7 EFFECTIVE DATE: OCTOBER 2011