Tack Rate Problem # CRS-2 Tack (Specific Gravity=.00) was applied to the roadway. The temperature measured from the tack distributor was 25 F. The length of the application was 000 feet. The width of the roadway was 2 feet. 75 gallons of tack were used to cover this section. What is the adjusted tack rate? Does this meet the SCDOT specifications? Tack application rate is NOT calculated using residual asphalt content. Step Calculate the square feet of roadway covered with tack,000 ft. x 2 ft. = 2,000 square feet Step 2 Calculate the square yards 2,000 square feet 9 sq. ft./sq. yd. = 333.33 sq. yd. Step 3 Correct number of gals. for temperature Reference CRS-2 (from table in SC-T-86) from a temperature of 25 F to 60 F M = 0.98375 75 Gallons x 0.98375 = 72.2 gallons of tack @ 60 F Step 4 Calculate the application rate gals./sq. yd. 72.2 333.33 sq. yds. = 0.29 gals./sq. yd. Answer Gals. / Sq. Yd. of emulsified asphalt at 60 F Answer: Yes or No Now, round off to 0.3 gals. sq. yd. Meet specs? Yes Tack Rate Problem #2 CRS-2 Tack will be applied to 2 foot wide roadway. The application will begin at Station 4+20 and end at Station 3+00. The temperature of the tack distributor is 40 F. How many gallons of CRS-2 are needed for an application rate of 0.05 gals/sq yd? Express answer in gallons to be applied by distributor. Answer Gallons @ 40º F Step Calculate the square feet of roadway covered with tack (300-420 ft.) x 2 ft. = 20,60 square feet Step 2 Calculate the square yards 20,60 square feet 9 sq. ft./sq. yd. = 2240 sq. yd. Step 3 Calculate number of gallons needed for 0.05 gals/sq yd application rate 0.05 2240 sq. yds. = 2 gallons (this is @ 60º F) Step 4 Correct number of gals. for temperature Reference CRS-2 (from table in SC-T-86) from a temperature of 60 F to 40 F M = 0.98000 2 gallons 0.98000 = 4.29 gallons Now: Round off to 4.3 gals of tack @ 40 F
HOMEWORK PROBLEM Tack Application Rate and Quantity Determine the tack application rate and the number of tons of tack used on this project. Use the following project information: ) Type of emulsion - SS- 2) Starting gallons 4,25 3) Ending gallons - 964 4) Length of roadway covered in tack 2. miles @ 26 feet wide 5) Temperature of tack - 40º F 7) Unit weight of SS- - 8.35 lbs./gals. (Round application rate to nearest 0.0 gals./sq. yd. and tons to 0.0 tons) Tack Application Rate and Quantity SOLUTION Step. Calculate # gals. of emulusifed asphalt used 4,25-964 = 3,287 gals. Step 2. Convert gals. to 60º F 3,287 x 0.98 = 3,22.3 gals. Step 3. Calculate sq. yds. of roadway tacked [2. (5280) x 26] / 9 = 32,032 sq. yd. Step 4. Calculate application rate (gals./sq. yd.) 3,22 / 32,032 = 0.006 or 0.0 gals. / sq. yd. Step 5. Calculate total tons of emulsified asphalt used (gals. used x unit wt.) / 2000 lbs./ ton (3,22 x 8.35) / 2000 = 3.45 tons 2
Asphalt Mix Rate # Asphalt mix was placed from station 0+00 to station 0+00. The lane width is 2 feet. How many tons of mix are needed to cover this section of roadway if the mix is placed at a rate of 50 pounds per square yard? Step Calculate the number of linear feet,000.0 0.00 = 000 linear feet Answer: Tons of mix Step 2 Calculate the sq. yds. of roadway (,000 ft. x 2 ft.) 9 sq. ft./sq. yd. = 333.33 sq. yd. Step 3 Calculate the pounds of asphalt mix needed to cover,333.33 sq. yd. x50 lbs./sq. yd. = 99,999.5 lbs. of mix Step 4 Calculate the tons of asphalt mix 99,999.5 lbs. 2000 lbs./ton = 99.99975 round off = 00.0 Tons Asphalt Mix Quantity # 2 Taper Section A lane that is 800 feet in length is 0 feet wide at the beginning and goes to 4 feet in width a the end. If you ran a rate of 25 pounds per square yard, how many tons would be needed to cover this section? Answer: Tons of mix Step Calculate the average width of the roadway (0 ft. + 4 ft.) 2 = 2 ft. average width Step 2 Calculate the sq. yds. of roadway (800 ft. x 2 ft.) 9 sq. ft./sq. yd. =,066.67 sq. yd. Step 3 Calculate the pounds of asphalt mix needed to cover,066.67 sq. yd. x 25 lbs./sq. yd. = 33,337.5 lbs. of mix Step 4 Calculate the tons of asphalt mix 33,337.5 lbs. 2000 lbs./ton = 66.7 Tons 3
Asphalt Mix Rate #3 You have determined that you have placed 5.7 tons of mix from Station 36+50 to Station 46+50. The width of paving is 2 feet. Your contract shows that the specified mix application rate is 50 pounds/sq. yd. What is your calculated mix application rate? What changes, if any, should be made to the paving operation? Answer: lbs./sq. yd. of mix Step Calculate the number of linear feet 4,650.0 3,650.0 =,000 linear feet Step 2 Calculate the sq. yds. of roadway (,000 ft. x 2 ft.) 9 sq. ft./sq. yd. = 333.33 sq. yd. Step 3 Calculate the pounds of asphalt mix placed 5.7 x 2,000 = 23,400 lbs. Step 4 Calculate the mix application rate 23,400 lbs.,333.33 sq. yd. = 73.55 lbs./sq.yd. Changes should be made to the paving operation since mix application rate is too high. Reduce thickness of mix placed by paver until calculated mix application rate is equal to 50 lbs./sq. yd. Roller Pattern st 00-ft Section (300-400 ft): Passes with Breakdown Roller until the mat breaks If more than 4, contact AME unless it is pneumatic rubber tire roller 3 passes each with Intermediate and Finish Rollers 4
Form 400.02 Field Determination Of Target Density For Asphalt Unique ID: Status: Date: 5/25/202 File No.: Road No.: Road Info: Southbound Contractor: Quality Pavers Inspector: R.U. Goode Operator: Tess Wright Offset: Distance: Station No: 3+00 to 4+00 Type of Mix: Surface Type B Thickness: 2" (220 psy) Lift: Standard Count: Control Strip No: SCDOT Gauge No: Roller / Mode Density Site Site 2 Site 3 Average Passes Density Temp. Density Temp. Density Temp. Density Remarks 39.4 38.6 40.2 39.4 2 40.9 40. 4.7 40.9 3 4.5 40.7 42.3 4.5 Use 4 4.4 40.6 42.2 4.4 Broke 42.2 4.5 43. 42.3 2 42.9 42.2 43.8 43.0 3 43.6 42.9 44.5 43.7 44.0 43.3 44.9 44. 2 44.4 43.7 45.3 44.5 3 44.3 43.6 45.2 44.4 Twelve Random Readings: 2 3 4 5 6 Note:Omit highest and lowest reading when calculating Target Density Established Target Density: Roller Pattern: Remarks: 5
Roller Pattern 2 nd 00-ft Section (400 500 ft): # Passes for Breakdown Roller determined on previous 00-ft section Passes with Intermediate Roller until the mat breaks If more than 4, contact AME unless it is pneumatic rubber tire roller 3 passes with Finish Roller Roller Pattern 3 rd 00-ft Section (500 600 ft): # Passes for Breakdown and Intermediate Rollers determined on previous two 00-ft sections Passes with Finish Roller until the mat breaks If more than 4, contact AME unless it is pneumatic rubber tire roller 6
Form 400.02 Field Determination Of Target Density For Asphalt Unique ID: Status: Date: 5/25/202 File No.: Road No.: Road Info: Southbound Contractor: Quality Pavers Inspector: R.U. Goode Operator: Tess Wright Offset: Distance: Station No: 4+00 to 5+00 Type of Mix: Surface Type B Thickness: 2" (220 psy) Lift: Standard Count: Control Strip No: SCDOT Gauge No: Roller / Mode Density Site Site 2 Site 3 Average Passes Density Temp. Density Temp. Density Temp. Density Remarks 40.4 39.6 4.2 40.4 2 4.9 4. 42.7 4.9 3 42.5 4.7 43.3 42.5 43.2 42.4 44.0 43.2 2 43.9 43. 44.7 43.9 3 44.6 43.8 45.4 44.6 Use 4 44.4 43.6 45.2 44.4 Broke 45.0 44.2 45.8 45.0 2 45.4 44.6 46.2 45.4 3 45.3 44.5 46. 45.3 Twelve Random Readings: 2 3 4 5 6 Note:Omit highest and lowest reading when calculating Target Density Established Target Density: Roller Pattern: Remarks: 7
Form 400.02 Field Determination Of Target Density For Asphalt Unique ID: Status: Date: 5/25/202 File No.: Road No.: Road Info: Southbound Contractor: Quality Pavers Inspector: R.U. Goode Operator: Tess Wright Offset: Distance: Station No: 5+00 to 6+00 Type of Mix: Surface Type B Thickness: 2" (220 psy) Lift: Standard Count: Control Strip No: SCDOT Gauge No: Roller / Mode Density Site Site 2 Site 3 Average Passes Density Temp. Density Temp. Density Temp. Density Remarks 39.9 39. 40.7 39.9 2 4.4 40.6 42.2 4.4 3 42.0 4.2 42.8 42.0 42.7 4.9 43.5 42.7 2 43.4 42.6 44.2 43.4 3 44. 43.3 44.9 44. 44.5 43.7 45.3 44.5 2 44.9 44. 45.7 44.9 Use 3 44.8 44 45.6 44.8 Broke Twelve Random Readings: 2 3 4 5 6 Note:Omit highest and lowest reading when calculating Target Density Established Target Density: Roller Pattern: Remarks: 8
Setting Target Density (600 900 ft): Use roller pattern just established 2 random density gauge readings Discard highest and lowest reading Target density is average of remaining 0 readings Example 2: Setting Target Density (600 900 ft): Between 300 and 600 feet, you just set a 3-4- 3 roller pattern For 600 to 900 feet, use roller pattern you just determined 9
Form 400.02 Field Determination Of Target Density For Asphalt Unique ID: Status: Date: 5/25/202 File No.: Road No.: Road Info: Southbound Contractor: Quality Pavers Inspector: R.U. Goode Operator: Tess Wright Offset: Distance: Station No: 6+00 to 9+00 Type of Mix: Surface Type B Thickness: 2" (220 psy) Lift: Standard Count: Control Strip No: SCDOT Gauge No: Roller / Mode Density Site Site 2 Site 3 Average Passes Density Temp. Density Temp. Density Temp. Density Remarks 40.2 39.4 4.0 40.2 2 4.7 40.9 42.5 4.7 3 42.3 4.5 43. 42.3 43.0 42.2 43.8 43.0 2 43.7 42.9 44.5 43.7 3 44.4 43.6 45.2 44.4 44.8 44.0 45.6 44.8 2 45.2 44.4 46.0 45.2 2 3 4 5 6 Twelve Random Readings: 45.9 44.8 44.9 45.5 44.2 45.8 46.2 44.6 45.6 44.4 43.9 45.2 Note:Omit highest and lowest reading when calculating Target Density Established Target Density: Roller Pattern: 3-3 - 2 45. Remarks: 0
Form 400.02 Field Determination Of Target Density For Asphalt Unique ID: Status: Date: 4/25/202 File No.: Road No.: Road Info: Northbound Contractor: Quality Pavers Inspector: R.U. Goode Operator: Tess Wright Offset: Distance: Station No: 6+00 to 9+00 Type of Mix: Surface Type B Thickness: 2" (220 psy) Lift: Standard Count: 2568 Control Strip No: SCDOT Gauge No: Roller / Mode Density Site Site 2 Site 3 Average Passes Density Temp. Density Temp. Density Temp. Density Remarks 39.2 38.8 39.4 2 40.6 40. 40.8 3 40.6 40.2 40.9 4.3 40.9 4.6 2 4.9 4.5 42.2 3 42.5 4.9 42.6 4 42.6 42.2 42.9 43.6 43.2 43.8 2 44.2 43.8 44.4 3 44.3 44.9 44.4 Twelve Random Readings: 44. 7 44.5 2 44.5 8 45.2 3 43.9 9 44. 4 44.2 0 43.8 5 44.9 44.2 6 44.3 2 44.4 Note:Omit highest and lowest reading when calculating Target Density Established Target Density: Roller Pattern: Remarks:
Example 2 Solution: Setting Target Density (600 900 ft): Take 2 random density gauge readings Discard highest and lowest reading Target density is average of remaining 0 readings Nuclear Gauge Locations You are placing Surface Course Type D in mainline paving at a width of 2 feet. At the beginning of the day, paving begins at Station 3+75 and ends at Station 47+05. The SCDOT Inspector randomly chooses to use the st set of random numbers. Determine the locations of your nuclear gauge readings in each sublot in accordance to SC-T-0 procedures. Step. Determine paving distance: 47+05 3+75 = 3,330 feet Step 2. Sublot size is 500 ft. Take one nuclear gauge reading for every 500 ft paved. 3,330 ft 500 ft = 6.66, so at least 6 nuclear gauge readings required; may need to take 7 Step 3. Determine the random locations of nuclear gauge readings in each sublot based on the selected random number table in SC-T-0 2
Form 400.02 Field Determination Of Target Density For Asphalt Unique ID: Status: Date: 4/25/202 File No.: Road No.: Road Info: Northbound Contractor: Quality Pavers Inspector: R.U. Goode Operator: Tess Wright Offset: Distance: Station No: 0+00 to 9+00 Type of Mix: Surface Type B Thickness: 2" (220 psy) Lift: Standard Count: 2568 Control Strip No: SCDOT Gauge No: Roller / Mode Density Site Site 2 Site 3 Average Passes Density Temp. Density Temp. Density Temp. Density Remarks 39.2 38.8 39.4 39. 2 40.6 40. 40.8 40.5 3 40.6 40.3 40.9 40.6 4.3 40.9 4.6 4.3 2 4.9 4.5 42.2 4.9 3 42.5 4.9 42.6 42.3 4 42.6 42.2 42.9 42.6 43.6 43.2 43.8 43.5 2 44.2 43.8 44.4 44. 3 44.3 44.9 44.4 44.5 Twelve Random Readings: 44. 7 44.5 2 44.5 8 45.2 3 43.9 9 44. 4 44.2 0 43.8 5 44.9 44.2 6 44.3 2 44.4 Note:Omit highest and lowest reading when calculating Target Density Established Target Density: Roller Pattern: 3-4 - 3 44.3 Remarks: 3
3,330 ft. 3+75 500 ft SUBLOT # st random number is 0.7 (longitudinal) st random number is 0.573 (transverse) Need to calculate if 7 th nuclear gauge shot needed; section less than 500 ft. 47+05 0.7 500 feet = 58.5 feet (or 3+75 + 59 = Station 4+34) [0.573 (2-2)] + = 6.73 feet from right edge SUBLOT #2 2nd random number is 0.724 (longitudinal) 2nd random number is 0.362 (transverse) 0.724 * 500 feet = 362 feet (or 3+75 + 500 + 362) = Station 22+37) [0.362 * (2-2)] + = 4.62 feet from right edge SUBLOT #3 3rd random number is 0.03 (longitudinal) 3rd random number is 0.5 (transverse) 0.03 500 feet = 6.5 feet (or 3+75 + 500 + 500 + 7) = Station 23+82) [0.5 * (2-2)] + = 6. feet from right edge POTENTIAL SUBLOT #7 7th random number is 0.493 (longitudinal) 7th random number is 0.20 (transverse) 0.493 * 500 feet = 246.5 feet (or 3+75 + (500 x 6) + 247) = Station 46+22) [0.20 * (2-2)] + = 3.0 feet from right edge Since we paved all the way to Station 47+05, we DO need to take the 7 th nuclear gauge shot. 4
CORE & DENSITY READING LOCATION WORK SHEET Date July 7 2025 Random Number Set Core/Gauge? Gauge Jane Doe Inspector File # 32B Sublots Length 500 Lane Width 2 Type Mix Surface D SUBLOT STA # RANDOM #'S FEET TO SAMPLE SAMPLE LOCATION rt or left lane 2 rt or left lane 3 rt or left lane 3+75 0.7 ( 0.7 ) ( 500 ft) = 58.5 3+75 + 59 = 4+34 Begin STA a a Sublot length c Begin STA c Core STA Location 8+75 0.573 ( 0.573) ( 2-2 ) + = 6.73 6.73 ft From Right Edge or Center Line End STA b b (lane width - 2) d d 8+75 0.724 ( 0.724) ( 500 ft) = 362 8+75 + 362 = 22+37 Begin STA a a Sublot length c Begin STA c Core STA Location 23+75 0.362 ( 0.362 ) ( 2-2 ) + = 4.62 4.62 ft From Right Edge or Center Line End STA b b (lane width - 2) d d 23+75 0.03 ( 0.03 ) ( 500 ft) = 6.5 23+75 + 7 = 23+82 Begin STA a a Sublot length c Begin STA c Core STA Location 24+25 0.5 ( 0.5 )( 2-2) + = 6. 6. ft From Right Edge or Center Line End STA b b (lane width - 2) d d 7 rt or left lane 43+75 0.493 ( 0.493) ( 500 ft) = 246.5 43+75 + 247 = 46+22 Begin STA a a Sublot length c Begin STA c Core STA Location 47+05 0.20 ( 0.20)( 2-2 ) + = 3.0 3.0 ft From Right Edge or Center Line End STA b b lane width - 2 d d Cores Nuclear Gauge Requirements apply to Intermediate B Special at rates < 300 psy; Intermediate A and B; Surface A and B Requirements apply to Base A, B, C and D; Intermediate B Special at rates > 300 psy; Intermediate C; Surface C and D per,500-ft sublot per 500-ft sublot Shawn Salley, SCDOT Resident Maintenance Engineer; Saluda County Revised /5/8 5
Core Locations (QA Specifications) You are placing Surface B in mainline paving at a width of 2 feet. Paving begins at Station 36+75 and ends at Station 90+90. The SCDOT Inspector randomly chooses to use the 2 st set of random numbers. Determine the locations of your roadway cores in accordance to SC-T-0 procedures. Step. Determine paving distance: 90+90 36+75 = 5,45 feet Step 2. Determine sublot distance. For mainline paving with Surface B mixes, the sublot distance is,500 feet, so there will be at least three cores taken, possibly four. Step 3. Determine the core locations based on random numbers. CORE # st random number is 0.853 (longitudinal) st random number is 0.6 (transverse) 0.853 *,500 feet =,280 feet (or 36+75 +,280 = Station 49+55) [0.6* (2-2)] + = 7. feet from right edge CORE #2 2nd random number is 0.489 (longitudinal) 2nd random number is 0.547 (transverse) 0.489 *,500 feet = 734 feet (or 36+75 +,500 + 734 = Station 59+09) [0.547 * (2-2)] + = 6.47 feet from right edge CORE #3 3rd random number is 0.800 (longitudinal) 3rd random number is 0.37 (transverse) 0.800 *,500 feet =,200 feet (or 36+75 +,500 +,500 +,200 = Station 78+75) [0.37 * (2-2)] + = 4.7 feet from right edge 6
CORE & DENSITY READING LOCATION WORK SHEET Date July 6 205 Random Number Set 2 Joe Blow Inspector File # A Sublots Length,500 Lane Width 2 Type Mix Surface B SUBLOT STA # RANDOM #'S FEET TO SAMPLE SAMPLE LOCATION rt or left lane 2 rt or left lane 3 rt or left lane 4 rt or left lane 36+75 0.853 ( 0.853) (,500 ft) =,280 36+75 +,280 = 49+55 Begin STA a a Sublot length c Begin STA c Core STA Location 5+75 0.6 (0.6)(2-2) + = 7. 7. ft From Right Edge or Center Line End STA b b lane width - 2 d d 5+75 0.489 (0.489) (,500 ft) = 734 5+75 + 734 = 59+09 Begin STA a a Sublot length c Begin STA c Core STA Location 66+75 0.547 (0.547)( 2-2 ) + = 6.47 6.47 ft From Right Edge or Center Line End STA b b lane width - 2 d d 66+75 0.8 (0.800) (,500 ft) =,200 66+75 +,200 = 78+75 Begin STA a a Sublot length c Begin STA c Core STA Location 8+75 0.37 ( 0.37 )( 2-2 ) + = 4.7 4.7 ft From Right Edge or Center Line End STA b b lane width - 2 d d 8+75 0.643 (0.643)(,500 ft) = 965 Station 9+40 past end of paving NO CORE Begin STA a a Sublot length c Begin STA c Core STA Location 96+75 0.85 ( )( ) + = NO CORE End STA b b lane width - 2 d d Cores Nuclear Gauge Requirements apply to Intermediate B Special at rates < 300 psy; Intermediate A and B; Surface A and B Requirements apply to Base A, B, C and D; Intermediate B Special at rates > 300 psy; Intermediate C; Surface C and D per,500-ft sublot per 500-ft sublot Shawn Salley, SCDOT Resident Maintenance Engineer; Saluda County Revised /5/8 7
CORE #4 4th random number is 0.643 (longitudinal) 4th random number is 0.850 (transverse) 0.643 *,500 feet = 965 feet (or 36+75 + (,500 x 3) + 965 = Station 9+40) [0.850 * (2-2)] + = 9.50 feet from right edge Fourth core will NOT be taken. However, if the station number for the fourth core had been before the ending station, the fourth core WOULD have been taken. Number of Cores (QA Specifications) The table below shows mainline paving distances for a given week. The type of mixture is Intermediate Type A. For each day, determine the number of cores required. Step. Determine sublot distance: For mainline paving with Intermediate A mixes, the sublot distance is,500 feet. So, for every,500 feet, you are guaranteed to cut a core. Step 2. Determine the number of cores required for each day in accordance with SC-T-0. 8
Monday 7,25 /,500 = 4.8 So, you are guaranteed to cut 4 cores required for each day in accordance with SC-T-0. Possibly cut 5 th core. Find the 5 th random number for longitudinal distance for the 43 rd set of random numbers. 5 th random number is 0.47 0.47 *,500 = 220.5 feet (meaning that you would have paved 220.5 feet into the 5 th sublot in order to cut the 5 th core. Check to see if a fifth core is needed. (4 *,500) + 220.5 feet = 6,220.5 feet from the beginning Station; Since 6,220.5 < 7,25, 5 th core will be taken. 5 cores will be taken on Monday Tuesday,360 /,500 = 7.57 So, you are guaranteed to cut 7 cores required for each day in accordance with SC-T-0. Possibly cut 8 th core. Find the 8 th random number for longitudinal distance for the 6 th set of random numbers. 8 th random number is 0.575 0.575 *,500 = 862.5 feet (meaning that you would have paved 862.5 feet into the 8 th sublot in order to cut the 5 th core.) Check to see if an eighth core is needed. (7 *,500) + 862.5 feet =,362.5 feet from the beginning Station; Since,362.5 >,360, 8 th core will not be taken. 7 cores will be taken on Tuesday 9
Wednesday 4,295 /,500 = 2.86 So, you are guaranteed to cut 2 cores required for each day in accordance with SC-T-0. Possibly cut 3rd core. Find the 3 rd random number for longitudinal distance for the 37 th set of random numbers. 3 rd random number is 0.30 0.30 *,500 = 465.0 feet (meaning that you would have paved 465.0 feet into the 3 rd sublot in order to cut the 3 rd core.) Check to see if a third core is needed. (2*,500) + 465.0 feet = 3,465.0 feet from the beginning Station; Since 3,465.0 < 4,295, 3 rd core will be taken. 3 cores will be taken on Wednesday Thursday Since 975 ft is less than,500 ft, no cores will be taken. 0 cores will be taken on Thursday 20
Friday 2,475 /,500 =.65 So, you are guaranteed to cut one core required for this day in accordance with SC-T-0. Possibly cut two cores. Find the 2 nd random number for longitudinal distance for the 22 nd set of random numbers. 2 nd random number is 0.243 0.243 *,500 = 364.5 feet (meaning that you would have to pave 364.5 feet into the 2 nd sublot in order to cut the 2 nd core.) Check to see if second core is needed. ( * 500) + 364.5 =,864.5 feet from the beginning Station; Since,864.5 < 2,475, 2 nd core will be taken. 2 cores will be taken on Friday Calculations on Cores # Based on the information given calculate the volume, bulk specific gravity and bulk density. Then calculate the average bulk density of the cores. Given: Core # Core #2 Weight in air Weight in air SSD Weight in water 90 9 679 Weight in air Weight in air SSD Weight in water 96 98 682 Core # 90 = 90 = 2.324 x 62.4 = 45.02 lbs./cu. ft. 9 679 52 Note: Water = 62.4 lbs./cu. ft. 52 is the volume of core # (cu. Cm.) 2.324 is the bulk specific gravity 45.02 is the bulk density Core #2 96 = 96 = 2.38 x 62.4 = 44.64 lbs./cu. ft. 98 682 56 Average Bulk Sp. Gr. = (2.324 + 2.38) 2 = 2.32 Average Bulk Density = (45.02 + 44.64) 2 = 44.83 lbs./cu. ft. A B C A B-C 2
Calculations on Cores From the information below, calculate the percent of compaction of the roadway cores. The average daily maximum Specific Gravity = 2.445 Given: Core # Core #2 Weight in air Weight in air SSD Weight in water 258.0 264.0 227.8 Weight in air Weight in air SSD Weight in water 2228.0 2323.0 324.7 Core # 258 = 258 = 2.305 Bulk Specific Gravity 264-227.8 936.2 (2.305 2.445) x 00 = 94.27 or 94.3% of average max. Sp. Gr. Core #2 2228 = 2228 = 2.232 = Bulk Specific Gravity 2323-324.7 998.3 A B C A B-C (2.232 2.445) x 00 = 9.29 or 9.3% of average Max. Sp. Gr. 22
Asphalt Roadway Technician Slope Problems: Examples ) You are resurfacing a roadway that currently has 0% slope and a width of 2 feet. You are going to make a slope correction to 2%. Calculate the difference in elevation from the lower edge of the pavement to the upper edge. Step One: Convert feet to inches 2 x 2 = 44 inches Step Two: Calculate 2% of 44 inches.02 x 44 = 2.88 inches 2.88 in. 2) The current roadway has a slope of 48:, but needs to be corrected for a curve section that needs to be 24:. The width of the pavement is 0 feet. Calculate the necessary elevation change for this section. Step One: Convert feet to inches 2 x 0 = 20 inches Step Two: Calculate elevation at 48: [(/48) x 20] = 2.5 inches Step Three:Calculate elevation at 24: [(/24) x 20] = 5.0 inches Step Four: Calculate elevation change: 5.0 in. 2.5 in. = 2.5 inches 24: slope 5.0 in. 2.5 in. 48: slope 3) The roadway is 4 feet in width, and the road requires a 48: slope, what should be the change in elevation (height)? Step One: Convert feet to inches 4 2 = 68 in. Step Two: Calculate elevation at 48: [(/48) 68] = 3.5 inches 3.5 in. 23