CHAPTER 5 CONCRETE PAVEMENTS - TU Delft

In some case gravel may be used as coarse aggregate in the concrete mix. For
heavily trafficked pavements however crushed stone shall be used to improve the
skid resistance. Because of the difference in costs between gravel and crushed stone
in those cases the concrete pavement is sometimes constructed in two sub-layers
(‘wet in wet’, i.e. by means of two slipformpavers closely behind each other), i.e. a
bottom layer of gravel concrete and a 60 to 80 mm thick upper layer of stone
concrete. The alternative of course is to use stone concrete over the whole concrete
pavement thickness, in this case only one slipformpaver is required.
The most important properties (with respect to the design of concrete pavement
structures) of some Dutch concrete qualities are shown in table 5.1.
Generally on heavily loaded concrete pavements, such as motorways and airport
platforms, the concrete quality B45 is used. On lightly loaded pavements (bicycle
tracks, rural roads, etc.) mostly concrete quality B35 and sometimes B45 is applied.
The concrete quality B55 is used for precast elements such as concrete blocks, tiles
and edge restraints (kerbs).
concrete quality
Property B25 B35 B45 B55
Mean cube compressive strength
(N/mm²) after 28 days
33 43 53 63
Characteristic* cube compressive
strength (N/mm²) after 28 days
25 35 45 55
Characteristic* compressive
strength (N/mm²) of cylinders taken
from the pavement after 28 days
20 28 36 44
Characteristic* splitting strength
(N/mm²) after 28 days
Characteristic* flexural tensile
strength (N/mm²):
2.25 2.75 3.25 3.75
after 28 days
3.5 4.2 4.9 5.6
after 90 days
3.9 4.6 5.3 6.0
Dynamic modulus of elasticity
(N/mm²)
30500 32500 34500 36500
Density (kg/m 3 ) 2300 – 2400
Poisson’s ratio 0.15 – 0.20
Coefficient of linear thermal
expansion (°C -1 )
1 x 10 -5 – 1.2 x 10 -5
* 95% probability of exceeding
Table 5.1: Mechanical properties of (Dutch) cement concrete for concrete pavement
structures (2,3).
Extensive information about the manufacturing of the concrete mix and the
construction of concrete pavements can be found in (4,5,6).
Immediately after construction the fresh concrete has to be protected against drying
through a curing compound, wet jute bags or a roof structure.
In plain concrete pavements furthermore joints have to be realized within 12 to 24
hours after construction of the pavement. This is necessary to prevent uncontrolled
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