Nowadays, the remote acquisition and mapping of physical parameters of soils and road surfaces has gained importance in the field of road engineering, as it facilitates the collection of large-scale data, which, unlike conventional methods, which provide results from specific sites, allows real-time parameter estimates to be obtained over large areas. This allows for a more comprehensive and accurate analysis of crucial characteristics such as moisture, bulk density, salinity or surface roughness, which are essential for road design, maintenance and rehabilitation.

ACCIONA is at the forefront in the development of smart highways and roads, having built more than 5,000 kilometres of roads in more than 25 countries, reflecting its commitment to sustainable progress and technical innovation. Mapping road parameters using non-intrusive methods will enable real-time collection of critical data in the management of roads and other linear works. Conventional soil and pavement parameter measurement systems such as moisture, density and salinity provide results at specific, point locations, acquisition is slow over large areas, results are not always representative of a section under study.

These conventional methods require an operator to measure manually with a nuclear densimeter, a conductivity meter or other equipment at individual points directly on the road, or to take samples and proceed to their analysis in the laboratory, which means taking as many samples as necessary to characterise a section, carrying out the laboratory tests and waiting several days to obtain the result. They do not allow massive data collection and it is not possible to have a mapping of soil moisture that would allow a complete picture to be obtained. In the case of surface roughness, it is not currently being measured.

Real-time mapping of road parameters enables instantaneous collection and analysis of critical data for road infrastructure management. Real-time monitoring improves operational efficiency, optimises resource allocation, and raises safety and sustainability standards. Determining soil moisture, density, salt content and surface roughness with remote systems that allow homogeneous measurement is a competitive advantage in large linear works, with large extensions, compared to the current conventional system.

ACCIONA launches this challenge to identify a solution for mapping the physical parameters of soils and pavements in road layers by means of massive and instantaneous data acquisition by indirect methods. The solution must allow:

• Estimate parameter values in road section layers, from soils to cement-treated and asphalt-bound materials (i.e. embankments, sub-bases and bases).
• Determine the moisture, bulk density, salinity and surface roughness of material in road pavements and other linear structures.
• Know the distribution of moisture, bulk density, salinity or surface roughness in the soil, differentiating between different types of soil.
• Acquire data in a non-intrusive way without affecting the line of work, reducing the time needed for data collection.