GRID | Roadway diagnostics

IRI coefficient

Longitudinal irregularities in the roadway are measured by the International Roadway Index (IRI), which is determined at each point in the longitudinal profile system at 25 cm intervals. This is a so-called sliding solution in which the calculation is made according to the standard from the section 10 m before and 10 m after this point.

Longitudinal unevenness 4 m

In this case, the unevenness of the roadway is determined by a system of dense longitudinal profiles on a detailed surface model. The modelling of the surface and the subsequent calculation is the basis for the determination of the roughness by simulation of the measuring lath.

Transverse unevenness 2 m – rutted tracks

As in the case of longitudinal roughness, the transverse roughness determination is based on a system of dense profiles on a detailed surface model, this time transverse. The calculation uses a standard geometric problem, using a slice through the surface of a digital surface model.

Droplet flow simulation

From the detailed terrain model of the roadway, we are able to generate a theoretical flow of water during rain, i.e. which way the water moves and to what extent.

Theoretical water depth in the tracks W

The theoretical water depth is determined in a similar way to the road roughness. The result is the water depth values, i.e. the depth of the rut, defined in millimetres. The water depth is then displayed by a colour scale of values.

Slope of the road in the area

This involves marking out areas with critical slopes with regard to water runoff pursuant to ČSN 73 6101 Design of roads and motorways. This is an analysis that identifies risk spots on the roadway.

Concentration of runoff

Based on the detection of water movement and a detailed model, we determine the locations where water accumulates and does not drain, including the area and depth of such locations. This is the detection of crisis locations where there is a risk of aquaplaning.

Relative inequalities

This is a metric for determining local inequality in a local area. Unlike previous analyses, it identifies inequalities in general, regardless of direction. This process assists the assessor in identifying problem areas on the roadway.

DTM elevation change

This is a shaded digital model that is interpreted by contours with a high base interval of usually 5 cm or 10 cm. This density then helps to orientate the roadway in terms of height.

Contour model

Based on the detailed terrain model, we can draw a detailed contour model to determine the level, transverse and longitudinal parameters and roadway geometry.

Roadway diagnostics