Digital geotechnical twin for control during excavation work and associated mass handling

BackgroundWhen a road, bridge or house is to be built,the geotechnical conditions are needed. All information is collected with geotechnical drill rigs to varying extents depending on the stage of a project.

The results from the field and laboratory investigations are then interpreted for soil types, depth to rock, degree of contamination, etc. and reported as a description of the foundation conditions.All this information can today be managed, visualized and used for further analyzes in the digital tool GeoBIM in Teams, which has been systematically developed since 2013.

A major advantage of having all geotechnical information from the design stage collected in a publicly available tool is that most of players in the civil engineering industry have access to all information without any advanced CAD or GIS licenses.Measuring movements and geotechnical changes in the construction phase is expected to save resourcesThe geomodel interpreted in the design, i.e. the description of the foundation conditions, is used as a basis for the procurement of a contractor who will build the facility, for example a bridge that requires a deep foundation.

All major excavation work requires support structures in the form of sheet piles and often also groundwater lowering.

All excavation work and geotechnical measures lead to changes in the geotechnical conditions and cause stresses and movements in installed geostructures.For all these changes and movements there are demands on continuous measurement and reporting so that they can be reconciled with the demands placed on max/min levels in control programs.

The current project will via standardized delivery specifications, further develop the existing GeoBIM platform with functionality to also be able to read in, visualize and manage so-called streaming data from geotechnical sensors in the construction phase.The main user in need is the contractor, who has an interest in being able to confirm that, for example, the installed sheet pile follows the behavior for which it was designed.

By constantly having control over how soil, groundwater, etc. behave, the contractor has the opportunity to be proactive if modifications need to be made.

In this way, it is expected that unforeseen interruptions in the planned construction process can be avoided and thus large resources can be saved.

Climate declarations require communication of geotechnical information to new playersThe Swedish Transport Administration, Swedish National Board of Housing, Building and Planning and the City of Stockholm are actors that already require that information on the geotechnical properties of excavated masses can be traced throughout the entire construction process.

A central such characteristic is values ​​of the masses´ CO2eq.

The requirement is set because all actors who handle excavated materials, such as transport companies and reception facilities, must be able to make sustainability reports for all material they handle.As a common digital system, the BEAst is chosen, which is a standardized system for the classification of digital objects and adapted for trade between different parties via, among other things, digital waybills.The current R&D project will supplement the digital geotechnical objects handled in the GeoBIM concept with climate-related information adapted to the BEAst system´s delivery specifications, e.g.

CO2eq, for the digital objects delivered from the construction stage, e.g. excavated material.

When a truck leaves the construction site with a flatbed filled with excavated materials, the volume is automatically scanned and its geotechnical and climate-related characteristics are conveyed from the GeoBIM database into the transport company´s BEAst system.

On arrival at the reception facility or another construction site where the masses are to be used, the digital information is forwarded to the receiver´s system without loss of information. In this way, all actors have the opportunity to fulfill the r