Asphalt paved road construction guide

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sampling

Loose asphalt mixture sample to be collect @ every 300 tons or once in a day at least. Checking parameter as follows--

  1. Temperature, minimum 139 degree C.
  2. Asphalt binder content
  3. Mineral aggregate gradation
  4. Theoretical maximum specific gravity
  5. Marshal stability and flow
  6. Air voids in compacted mixture

Compacted core sample of 100 mm dia @ 1 per 300 Rmtr or once in a day at least. Checking parameter as follows—

       a)Thickness of specimen must be within (+-)10 mm for base course and (+-)6mm for wearing course
       b)Degree of compaction 93-95% of max. theoretical specific gravity for base course and 93-96% for wearing course
       c)Bulk specific gravity and bulk density
       d)Air voids in compacted mixture
       e)Marshal stability and flow

Laboratory report for above to be submit within 24 hours from sample taken in accordance with ---

      a)Density voids analysis
      b)Absorption of cement quantity in kg for each mixture
      c)Percent air voids
      d)Percent voids in minerals

execution

Below scenario to be fulfilled before and during asphalt operation--

1.Ambient temperature must be more than 10 degree C
2.Asphalt mix temperature should be minimum 139 degree C
3.Prime coat with MC1 or MC 70 @ 0.65 to 1.75 ltr/SqM. Apply on prepared dirt free base and left for minimum 48 hours to evaporate volatiles and penetration into base.
4.Tack coat with RC2 or RC250 @ 0.25 ltr/SqM. Apply before asphalt mixture laying and accept to dry. Provide 150mm and 600mm minimum lap for longitudinal, transverse joint direction, respectively.asphalt mixture laying and accept to dry. Provide 150mm and 600mm minimum lap for longitudinal, transverse joint direction, respectively.
5.Asphalting with paver or manually with minimum 3 Mtr. Plan to compact layer from lower grade/slope first along centerline. Surface smoothness/undulation tolerance 12mm and 5mm for base course and wearing course.

6.Inert/filler materials may be approved one like lime stone dust, pulverized lime stone or marble dust.

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