As per IRC SP 20 guideline, a powerpoint presentation on specification and requirements in the design of special pavement has been made.

1. Design of special
Pavements
(as per IRCSP 20-2002)
Presented by: RUOKUOMENUO RIO
M.Tech HT , 1st Semester
Rural Roads
Lecture-in-charge: Mrs.Ranjitha J

2. Special pavements
DOUBLE HERRINGBONE (pattern adopted)

3. Design criteria
1. Materials for special pavement
i.e Concrete Block Pavement
(CBP)/Interlocking Concrete Block
Pavement(ICBP)
2. Concrete mix
3. Specifications
4. Stone-sett pavement or bridge on edge
pavement

4. 1.Materials for special pavement
Concrete Block Pavement (CBP)
 Concrete blocks are used
which are non-interlocking
when paved.
Interlocking Concrete block
Pavement (ICBP)
 Blocks with curved vertical
faces are used.

5. CBP/ICBP
 Produced from Block Making Machines (BMM)
 Blocks are allowed to self cure under ambient
temp. i.e 24 hours during mild season and 12 to 18
hours during summer.
 Transferred to curing tanks or gunny bags- cured
for 28 days to achieve full strength
 When BMM’s are unavailable, manual or semi-automatic
hydraulic presses are utilised.
 Manual or power driven mixers are used for
preparation of concrete mix.
 Curing is done either in curing tanks- capacity for
holding 2 weeks’ production of blocks or else by
wet gunny bags or hessian cloth.

6. Fig 1: Block Making Machine
Produces ICBP, building blocks, kerb stones etc.
High standard and meets international quality
requirements.
ISO certified

8. Fig 2: Curing tanks

9. Paving block curing

10. Gunny bags/hessian cloth

11. Curing being done in columns using gunny bags (inset)

12. General features and
requirements:
Consists of surface layer
of brick-sized concrete
blocks paved on thin,
compacted bedding sand
layer of specified grading.
Spread over profiled
base course bounded by
edge restraints .
Joints are sealed with
joint filling sand.
 A good drainage layer is
provided over compacted
sub-grade for satisfactory
performance of CPP/ICBP.

13. Edge restraints

14. 2.Concrete mix
 Ordinary Portland cement/ Portland Pozzolana
Cement/Portland Slag Cement are used as
binders.
Good quality natural coarse and fine aggregates
as per IS:383-1970 should be used in concrete.
 Industrial waste material such as fly ash ,slag etc.
can be used as additives.
Potable water should be used for making
concrete mix.
Blocks so produced should have equivalent 28-
days strength as per design requirements.

15. Grading of concrete mix
Serial no Blocks meant for Grade
1. Paving rocks carrying
traffic
M-30 or higher
grade
2. Non-traffic area like
footpaths
M-25 or higher
grade (60mm thick
block)
3. Precast edge
restraints
M-25 or higher
grade (1:1:2)

16. 3.Dimension and Thickness
Serial no Type Specification (as per
IS:SP20-2002)
1 Precast edge restraint 150X150X300 mm
2. Top surface area of
blocks
200-500cm²
3. Breadth-to-length ratio
of rectangular blocks
1:2
4. Length of rectangular
blocks
200 to 220mm
5. Width of rectangular
blocks
100 to 110 mm
6. Colour of block Natural cement or
special colour by using
organic or inorganic
pigments.

17. Serial no Type Specification
7. Cement treated
marginal agg. as base
course
67 per cent of the
granular base course.
8. Lime fly ash bound
macadam and lime fly
ash concrete as base
layer
67 per cent of the base
course.
9. Bedding sand Thickness of 30mm
10. Base course Minimum thickness
100mm

18. Natural sandstone used for paving.

19. Design chart for granular base i.e Thickness of granular base layer
Eg: For 54 CVPD, and CBR=4%
thickness=250mm

20. Recommended grading for bedding
and joint filling sand.
Serial
no
IS Sieve size (mm) Zone- II (IS:383-1970)
(for bedding sand)
Per cent passing
Zone- IV (IS:383-1970)
(for joint Filling Sand)
Per cent passing
1. 10.00 100 100
2. 4.75 90-100 95-100
3. 2.36 75-100 95-100
4. 1.18 55-90 90-100
5. 0.60 35-59 80-100
6. 0.30 8-30 15-50
7. 0.15 0-10 0-15
8. 0.075 0-3 0-5

21. 4. Stone-sett pavement/brick on edge
pavement
 It is used only
for areas
having very
poor drainage
and pedestrian
pathway.
 Cobblestone
available from
river beds can
also be used
for paving.
Brick on edge pavement
Cobble stones

22. Type of stones normally used for
stone-sett pavements are:-
Granite Basalt

23. Sandstone Limestone

24. Bricks are laid on edge over bedding
sand.

25. Specification of stone-sett/ brick on
edge pavement.
 Stone cut to regular sizes should normally have dimension
of 100 to 150mm diameter and 90 to 100mm thickness.
 For brick pavement, burnt clay or bricks having minimum
28 days compressive strength of 7MPa.

26. Availability of Concrete Block Pavements in various shapes and sizes.

27. Reference:
IRC SP 20:2002
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