Page 143 - RoadCem Manual - PCT BV

5.7 Determination of Stabilized (Bound) Material Properties 5.7.1 General
Once the mix design is chosen, the amount of material, cement, fly-ash and RoadCem, are known and a new composite material is created. This new material will have certain properties, depending on the composition. These properties will determine the pavement structure design. For example, the layer thickness and lifespan of the pavement structure are based on these properties as well as the stresses and strains that occur in the final pavement structure.
The material properties that need to be determined are shown in the figure 5.32:
Figure 5.32 Determine most important physical material properties for road dimensioning.
When material properties have higher values compared to the traditional materials then a better pavement structure will be built. Before actual construction takes place the properties of each project must be examined and checked. The reason is that each sub-base is unique and there is always a possibility that the properties of the material deviate from the general recommendations discussed previously. If any of the properties show unacceptable values then the mixture composition needs to be changed. The methods used for the measurement of the different material properties are given next.
5.7.2 Comressive strength
Compressive strength is measured by applying a known pressure (or a loadin) to a sample speciment and observing the pressure needed to cause the failure of the specimen. Special testing equipment is needed. The rate at which pressure is applied is also controled.
A minimum value for compressive strength of 2 MPa is needed after 48 hours and 4,2 MPa after 28 days. These are higher values in comparison with the values obtainable with all traditional hydraulic materials with the exception of concrete.
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