The planning of new road infrastructure is a challenging task. Accurate alignment and designs are needed to meet safety compliances, environmental requirements, and the regulations laid down by public authorities. The geometric designs of roads are required to follow engineering processes and practices. They include road cross-sections, linear alignments, and the corresponding roadside environment. Regardless of whether the road is constructed in a rural, urban or interurban region, the geometric design and model of all visible features have to be considered well in advance. 

The uniqueness of the designs and models of the roads lies in the amount of data available for processing. The existing roads, buildings, and important features of terrains have to be considered for proper new roads and infrastructure planning. Digital Terrain Models (DTMs), CAD applications, and the data related to the terrain where roads are to be built are providing new possibilities to the design process. 
Read on to know how unlike traditional models and designs, 3D modeling of surface objects and lines are presenting innovative infrastructural capabilities. 

Application of Digital terrain Model in Road Design 

1. Landslide identification

Digital terrain models (DTMs) attained with the help of ground-based laser scans offer high-resolution models of the bare earth. DTMs are applied to curvatures and slopes in complex landslide terrains for landslide identification.
A thorough understanding of the terrain surface is possible using the resultant elevation models. 
The smallest of geomorphological features like back-tilted slope units, irregular topography, lobate accumulation, zones and scraps are put to use for delineating and classifying landslides. Terrestrial DTM data provides helpful methods of landslide mapping through shaded relief models and topographic roughness filters.
2. Forest road mapping and design

Digital terrain modelling fills the gaps of traditional, simple and coarse ALS data.

– The advanced algorithms developed for new age DTMs are well adapted to handle the needs of the minutely detailed terrain descriptions. 
– Nowadays, airborne laser scanning (ALS) is used for generating DTMs for high vegetation, difficult-to-penetrate terrains. 
– The information derived from high-resolution DTMs is useful for diverse geo-related applications like natural hazard process modelling, hydrology, and geomorphological mapping. 
– DTMs depict anthropogenic and terrain features of the kinds of geological lineaments, erosion scarps, walking paths, open spaces and roads

3. Designing highways

DTMs have always been a favorite tool in the hands of engineers specializing in highway designs. They present an array of sequenced values that define the spatial distribution of diverse features on the surface of the earth. DTM-backed detailed object information, economical information, geomorphic information, and the data related to natural resources and the surrounding environment is critical for highway planning and design. In case the DTMs are used for describing and expressing spatial information like elevations and terrain relief, the models are referred to as Digital Elevation Models or DEMs.

4. Road planning in urban congested areas

DTM extraction is most challenging in dense urban areas. Reliable and valuable data has to be derived from tiny open areas.

  • The appropriate algorithms are then put in place for reconstructing the terrain after discarding the existing infrastructures. For instance, aerial photogrammetry and LiDAR are used for determining the relative accuracy of 3D reconstructed surfaces for planning road designs in urban centres.
  • Filters are applied to DTMs in line with the built-structure characteristics to help construction companies figure out the most precise models. 
  • Alongside, Digital Surface Models (DSMs) are used for providing time and cost-efficacy in road designs for urban areas. 
  • LiDAR and digital photogrammetry, combined with aerial/satellite stereoscopic imagery are also helping road design and modelling tasks in congested urban terrains. 

SBL– Geospatial Services 

At SBL, we enable flexible DTM-enabled construction processes for all kinds of infrastructure development projects, road construction included. We help firms discover and exploit reliable geospatial data for further analysis and use. Reach out to our exhaustive range of cost-effective and accurate geospatial services to boost your ROI and functionality. Ask for our result-oriented geospatial strategies and solutions to get the competitive edge. Visit us ( to know about DTMs in road planning and design – right away!