Page 19 - Microsoft Word - 20120528 Unesco study

Clay

Sand

Sandy clay

Figure 2.2: Grain size distribution of different soil types

Using the USCS classification system and a pre study of the occurring soils, four main classes
are determined as follows:
- Soil type 1: Organic clays.
- Soil type 2: Clays.
- Soil type 3: Sandy clays.
- Soil type 4: Sand.

There are maps which show the soil types available in the region. These soil types have to be
classified into the four main classes.

Road infrastructure
The SCT use a classification system for the Road infrastructure in Mexico. In this classification,
the roads are divided into five classes:
- Road type 1: Highways.
- Road type 2: Primary roads.
- Road type 3: Secondary roads.
- Road type 4: Rural roads.
- Road type 5: Access roads.

The Road types are determined on the basis of the expected traffic intensity. For this study the
same classification system is used.

The road infrastructure is partly available via open street maps. The missing roads are drawn
manually using an underlay of Google Earth.

Part of the road infrastructure has already been constructed using the PowerCem Technology.
To validate the final model and to get an impression of the benefits of the PowerCem
Technology these roads have to be specified. The information regarding the PowerCem based
roads is provided by PowerCem Mexico.

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