Quality Assurance Handbook for Rural Roads Volume-I - pmgsy

B. Quality Control Requirements
1. Materials
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Quality Assurance Handbook for Rural Roads
(i) The quality control requirements for the materials in the subgrade, 100 mm GSB and 75 mm
WBM (Grading 2) Base as given in Sub-section 303. 401 & 405 shall apply.
(ii) The Stone sets should be rectangular in shape, 250-300 mm in length, 150- 200 mm in
width and 150 mm in depth, with tolerance of (±) 12 mm.
(iii) Edge stones should be 350 – 400 mm in length, 150-200 mm in width and not less than 350
mm in depth
(iv) The Stone set should meet the following physical requirements.
(a) Aggregate Impact Value (IS:2386 Part 4) not more than 30
(b) Water Absorption (IS:2386 Part 3) not more than 2%
(c) Polished Stone Value (BS:812 Part 114) not less than 55
(v) Stones normally used are Granite, Basalt, Sandstone and Limestone. Stones from Sedimentary
rock should not be used.
(vi) The stone sets should be hammer-dressed on top to the extent that the maximum depression
of the dressed surface from a straight edge applied across any part of the surface does not
exceed 20 mm. The dressing on the sides should be similarly carried out so as to obtain a
mortar joint not exceeding 20 mm in width.
2. Horizontal Alignment
The edges of the stone set pavement should be correct within a tolerance limit of (±)20 mm in
plain and rolling terrains and (±) 30 mm in hilly terrain.
3. Surface Levels
The tolerance in surface levels of a Stone Set Pavement will be restricted to (±) 15 mm. A grid of 10
m x 2.5 m may be formed to check the surface level.
4. Surface Regularity
The maximum permitted difference between the Stone Set Pavement and 3 m straight edge should
be 12 mm for longitudinal profile and 10 mm for cross profile.
C. Do’s and Don’ts
Do’s Don’ts
1. The Stone sets should not only be tested for AIV and
water absorption, but also for the Polished Stone
Value.
2. The types of Stones normally found suitable are
Granite, Basalt Sand-stone or Limestone.
3. Make sure that the bedding layer is a properly
graded coarse sand with a compacted thickness of
40 mm.
1. Do not use any Sedimentary stone in the Stone Set
Pavement.
2. Do not open the road immediately to traffic if sandcement
mortar is used for filling joints.
3. Do not leave the stone sets uncompacted into the
bedding layer.