AASHTO T 191-2014 Standard Method of Test for Density of Soil In-Place by the Sand-Cone Method.pdf

1、Standard Method of Test for Density of Soil In-Place by the Sand-Cone Method AASHTO Designation: T 191-14 American Association of State Highway and Transportation Officials 444 North Capitol Street N.W., Suite 249 Washington, D.C. 20001 TS-1b T 191-1 AASHTO Standard Method of Test for Density of Soi

2、l In-Place by the Sand-Cone Method AASHTO Designation: T 191-14 1. SCOPE 1.1. This method is intended for determining the in-place density of soils. The apparatus described herein is restricted to tests in soils containing particles not larger than 50 mm (2 in.) in diameter. 1.2. The following appli

3、es to all specified limits in this standard: For the purposes of determining conformance with these specifications, an observed value shall be rounded off to “the nearest unit” in the last right-hand place of figures used in expressing the limiting value, in accordance with the rounding-off method o

4、f ASTM E29. 2. REFERENCED DOCUMENTS 2.1. AASHTO Standards: M 231, Weighing Devices Used in the Testing of Materials T 19M/T 19, Bulk Density (“Unit Weight”) and Voids in Aggregate T 99, Moisture-Density Relations of Soils Using a 2.5-kg (5.5-lb) Rammer and a 305-mm (12-in.) Drop T 217, Determination

5、 of Moisture in Soils by Means of a Calcium Carbide Gas Pressure Moisture Tester T 265, Laboratory Determination of Moisture Content of Soils 2.2. ASTM Standards: D4643, Standard Test Method for Determination of Water (Moisture) Content of Soil by Microwave Oven Heating D4959, Standard Test Method f

6、or Determination of Water (Moisture) Content of Soil By Direct Heating E29, Standard Practice for Using Significant Digits in Test Data to Determine Conformance with Specifications 3. APPARATUS 3.1. Density Apparatus with Base PlateThe density apparatus shall consist of a 4-L (1-gal) jar and a detac

7、hable appliance consisting of a cylindrical valve with an orifice 12.7 mm (1/2in.) in diameter and having a small funnel connecting to a standard G mason jar top on one end and a large funnel on the other end. The valve shall have stops to prevent rotating the valve past the completely open or compl

8、etely closed positions. The base plate shall be made of metal and sufficiently rigid. The plate shall have a flanged center hole to receive the large funnel. The apparatus shall conform to the requirements shown in Figure 1. The apparatus described here represents a design that has proven satisfacto

9、ry. Other apparatus of similar proportions will perform equally well so long as 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1b T 191-2 AASHTO the basic principles of the sand-volume determination

10、are observed. The base plate is required for calibrations and testing. Metric Equivalents in. mm in. mm 0.50 12.7 6.50 165.1 0.75 19.1 6.75 171.5 1.125 28.6 12 304.8 5.375 136.5 Figure 1Density Apparatus 2015 by the American Association of State Highway and Transportation Officials.All rights reserv

11、ed. Duplication is a violation of applicable law.TS-1b T 191-3 AASHTO 3.2. Calibration ContainerA sturdy cylindrical container of known volume (Vc). The container shall be dimensionally approximate to the largest test hole that will be dug. The container shall be calibrated according to T 19M/T 19.

12、Note 1The internal diameter of the container shall be equal to or slightly less than the diameter of the opening of the base plate used with the sand-cone. The 944-cm3(1/30-ft3) and 2830-cm3(1/13.33-ft3) molds specified in T 99 and T 180 are suitable. 3.3. SandAny clean, dry, free-flowing, uncemente

13、d sand having few, if any, particles passing the 0.075-mm or retained on the 2.00-mm sieves. In selecting a sand for use, several bulk density determinations should be made using the same representative sample for each determination. To be acceptable, the sand shall not have a variation in bulk dens

14、ity greater than 1 percent. 3.4. BalancesA balance conforming to the requirements of M 231, Class G 20. Also, a balance conforming to the requirements of M 231, Class G 2. 3.5. Drying EquipmentStove or oven or other suitable equipment for drying moisture content samples. 3.6. Miscellaneous Equipment

15、Small pick, chisels, or spoons for digging test hole; 254 mm (10 in.) frying pan or any suitable container for drying moisture samples; buckets with lids, canvas sacks, or other suitable containers for retaining the density sample, moisture sample, or density sand, respectively; small paintbrush, sl

16、ide rule, and notebook. 4. CONE CORRECTION AND BULK DENSITY FACTORS 4.1. Filling the apparatus: 4.1.1. Fill the apparatus with sand that is dried and conditioned to the same state anticipated during testing. Note 2The apparatus may be filled either with or without the metal funnel being attached. Th

17、e funnel may be removed and reattached as needed in order to fill the apparatus with the funnel detached. 4.1.2. Determine and record the mass of the apparatus filled with sand (m1). 4.2. Determine the mass of sand required to fill the funnel and base plate (cone correction). 4.2.1. Place the base p

18、late on a clean, level, plane surface. Invert the sand-cone filled with sand and seat the funnel in the recess of the base plate. 4.2.2. Open the valve fully, and allow the sand to flow until it stops (Note 2). 4.2.3. Close the valve sharply, remove the apparatus, and determine the mass of the appar

19、atus and the remaining sand (m2). 4.2.4. The mass of sand required to fill the cone and base plate is calculated by the difference between the initial mass (Step 4.1.3) and final mass (Step 4.2.3). Record this mass as the cone correction (Cc= m1 m2). (See Section 4.4.) 4.3. Determine the bulk densit

20、y of sand (DB) to be used in the field test. 4.3.1. Replace the sand removed in the funnel determination according to Section 4.1, close the valve, and determine the mass of the apparatus and sand (m3). 2015 by the American Association of State Highway and Transportation Officials.All rights reserve

21、d. Duplication is a violation of applicable law.TS-1b T 191-4 AASHTO 4.3.2. Position the calibration container on a clean, level, plane surface. Place the base plate on the calibration container (Note 1). Invert the apparatus and seat the funnel in the recess of the base plate. 4.3.3. Open the valve

22、 fully and keep open until the sand stops flowing (Note 2). 4.3.4. Close the valve sharply, remove the apparatus, and determine the remaining mass of the apparatus and sand (m4). 4.3.5. Calculate the mass of the sand needed to fill the container, funnel, and base plate. Subtract the final mass (Step

23、 4.3.4) from the initial mass (Step 4.3.1). 4.3.6. The mass of the sand needed to fill the container only is determined by subtracting the mass of the cone correction (Step 4.2.4) from the total mass required to fill the container with the funnel and base plate (Step 4.3.5). 4.3.7. Determine the bul

24、k density of the calibration sand (sand calibration factor). Determine the mass of the sand needed to fill the container three times and average the results. Divide the mass of the sand needed to fill the container (Step 4.3.6) by the volume of the calibration container as determined according to T

25、19M/T 19. DB= (m3 m4 Cc)/Vc4.3.8. Record this factor for future reference. (See Section 4.4.) 4.4. Each container/bag of sand will have a unique cone correction and sand calibration factor. Each sand-cone and matched base plate set will also have unique cone corrections and bulk sand densities. Cons

26、equently, each sand-cone and base plate should be marked and the associated correction/density factors recorded. 5. PROCEDURE 5.1. Determine the density of the soil in place as follows: 5.1.1. Fill the apparatus with sand according to Section 4.1. Record the total mass (m5). 5.1.2. Prepare the surfa

27、ce of the location to be tested so that it is a level plane. 5.1.3. Seat the base plate on the prepared surface. Dig the test hole inside the opening of the base plate, being very careful to avoid disturbing the soil that will bound the hole. Soils that are essentially granular require extreme care.

28、 Place all loosened soil in a container, being careful to avoid losing any material. Care must be taken to avoid moisture loss during excavation. 5.1.4. Place the apparatus on the base plate and open the valve. After the sand has stopped flowing, close the valve (Note 2). 5.1.5. Weigh the apparatus

29、with the remaining sand (m6) and record. 5.1.6. Weigh the moist material that was removed from the test hole. 5.1.7. Mix the material thoroughly and secure and weigh a representative sample for moisture determination. 5.1.8. Dry and weigh the soil sample for moisture content determination in accorda

30、nce with T 265 or in accordance with rapid methods such as T 217, ASTM D4959, or ASTM D4643. The results 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1b T 191-5 AASHTO obtained using these or other

31、 rapid test methods must be corrected to the values obtained in accordance with T 265. Calculate the moisture content to the nearest 0.1 percent. 5.1.9. The minimum test hole volumes suggested in determining the in-place density of soil mixtures are given in Table 1. This table shows the suggested m

32、inimum mass of the moisture content sample in relation to the maximum particle size in soil mixtures. Table 1Minimum Test Hole Volumes and Minimum Moisture Content Samples Based on Maximum Size of Particle Maximum Particle Size Minimum Test Hole, Volume Minimum Moisture Content Sample, g mm Alternat

33、e cm3ft34.75 No. 4 Sieve 710 0.025 100 12.5 1/2in. 1415 0.050 250 25.0 1 in. 2125 0.075 500 50.0 2 in. 2830 0.100 1000 6. CALCULATIONS 6.1. Calculate the volume of the test hole (VH): VH= (m5 m6 Cc)/DB(1) where: VH= volume of the test hole, m5= initial mass of the apparatus and sand, m6= final mass

34、of the apparatus and sand, Cc= cone correction, and DB= bulk density of the sand. 6.1.1. Calculate the volume of the test hole to the nearest 1 cm3(0.0001 ft3). 6.2. Calculate the dry mass of the material removed from the test hole as follows: MDS= (MWS/ (1 + (w/100) (2) where: MDS= dry mass of the

35、material removed from the test hole, MWS= moist mass of the material removed from the test hole, and w = percentage of moisture, in material removed from the test hole. 6.2.1. Calculate the dry mass of the material to the nearest 1 g (0.01 lb). 6.3. Calculate the in-place dry density of the material

36、 removed from the test hole as follows: DD= MDS /VH(3) where: DD= in-place dry density of the material removed from the test hole, MDS= dry mass of the material removed from the test hole (Section 6.2), and VH= volume of the test hole (Section 6.1). 2015 by the American Association of State Highway

37、and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.TS-1b T 191-6 AASHTO 6.3.1. Calculate the in-place dry density to the nearest 1 kg/m3 (0.1 lb/ft3). (See Notes 3 and 4.) Note 30.001 g/cm3= 1 kg/m3Note 4It may be desired to express the in-place density as

38、 a percentage of some other density, for example, the laboratory maximum density determined in accordance with T 99. This relationship can be determined by dividing the in-place density by the maximum density and multiplying by 100. 2015 by the American Association of State Highway and Transportation Officials.All rights reserved. Duplication is a violation of applicable law.