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Three-dimensional laser scanning for geometry documentation and construction management of highway tunnels during excavation.

Gikas V - Sensors (Basel) (2012)

Bottom Line: This paper discusses the use and explores the potential of laser scanning technology to accurately track excavation and construction activities of highway tunnels.Also, it discusses the planning, execution, data processing and analysis phases of laser scanning activities, with emphasis given on geo-referencing, mesh model generation and cross-section extraction.Specific case studies are considered based on two construction sites in Greece.

View Article: PubMed Central - PubMed

Affiliation: School of Rural and Surveying Engineering, National Technical University of Athens, 9 I Polytechniou Str., Zographou, Athens 15780, Greece. vgikas@central.ntua.gr

ABSTRACT
Driven by progress in sensor technology, computer software and data processing capabilities, terrestrial laser scanning has recently proved a revolutionary technique for high accuracy, 3D mapping and documentation of physical scenarios and man-made structures. Particularly, this is of great importance in the underground space and tunnel construction environment as surveying engineering operations have a great impact on both technical and economic aspects of a project. This paper discusses the use and explores the potential of laser scanning technology to accurately track excavation and construction activities of highway tunnels. It provides a detailed overview of the static laser scanning method, its principles of operation and applications for tunnel construction operations. Also, it discusses the planning, execution, data processing and analysis phases of laser scanning activities, with emphasis given on geo-referencing, mesh model generation and cross-section extraction. Specific case studies are considered based on two construction sites in Greece. Particularly, the potential of the method is examined for checking the tunnel profile, producing volume computations and validating the smoothness/thickness of shotcrete layers at an excavation stage and during the completion of excavation support and primary lining. An additional example of the use of the method in the geometric documentation of the concrete lining formwork is examined and comparisons against dimensional tolerances are examined. Experimental comparisons and analyses of the laser scanning method against conventional surveying techniques are also considered.

No MeSH data available.


Related in: MedlinePlus

Working principle for the static (a) and kinematic; (b) terrestrial laser scanners.
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f1-sensors-12-11249: Working principle for the static (a) and kinematic; (b) terrestrial laser scanners.

Mentions: Depending on the type of use, TLS can be operated either from a static position (mounted on a tripod) or from a dynamic platform (attached on a moving vehicle) [14,15]. In the first case, the TLS is used to produce a detailed map of the topographic features of the area around the static location that is occupied by the scanner, whereas in kinematic mode, it facilitates for conducting surveying and inventory maps of the corridor around the moving vehicle. The working principle of static TLS relies on repeated measurements of the slope range taken by an Electronic Distance Measurement (EDM) device at known angular intervals, which are defined at the horizontal and vertical planes passing through the origin of the EDM sensor. The outcome of this process is the spherical polar coordinates of the points in the field of view of the instrument in a local (topocentric) coordinate system. In contrast, in the case of kinematic laser scanning the device changes its position during data capturing. Therefore, a 3D point cloud emerges from the distance measurement, an angle measurement and the motion of the scanner [15]. Figure 1 offers a schematic view of the operation principle for both cases.


Three-dimensional laser scanning for geometry documentation and construction management of highway tunnels during excavation.

Gikas V - Sensors (Basel) (2012)

Working principle for the static (a) and kinematic; (b) terrestrial laser scanners.
© Copyright Policy
Related In: Results  -  Collection

License
Show All Figures
getmorefigures.php?uid=PMC3472883&req=5

f1-sensors-12-11249: Working principle for the static (a) and kinematic; (b) terrestrial laser scanners.
Mentions: Depending on the type of use, TLS can be operated either from a static position (mounted on a tripod) or from a dynamic platform (attached on a moving vehicle) [14,15]. In the first case, the TLS is used to produce a detailed map of the topographic features of the area around the static location that is occupied by the scanner, whereas in kinematic mode, it facilitates for conducting surveying and inventory maps of the corridor around the moving vehicle. The working principle of static TLS relies on repeated measurements of the slope range taken by an Electronic Distance Measurement (EDM) device at known angular intervals, which are defined at the horizontal and vertical planes passing through the origin of the EDM sensor. The outcome of this process is the spherical polar coordinates of the points in the field of view of the instrument in a local (topocentric) coordinate system. In contrast, in the case of kinematic laser scanning the device changes its position during data capturing. Therefore, a 3D point cloud emerges from the distance measurement, an angle measurement and the motion of the scanner [15]. Figure 1 offers a schematic view of the operation principle for both cases.

Bottom Line: This paper discusses the use and explores the potential of laser scanning technology to accurately track excavation and construction activities of highway tunnels.Also, it discusses the planning, execution, data processing and analysis phases of laser scanning activities, with emphasis given on geo-referencing, mesh model generation and cross-section extraction.Specific case studies are considered based on two construction sites in Greece.

View Article: PubMed Central - PubMed

Affiliation: School of Rural and Surveying Engineering, National Technical University of Athens, 9 I Polytechniou Str., Zographou, Athens 15780, Greece. vgikas@central.ntua.gr

ABSTRACT
Driven by progress in sensor technology, computer software and data processing capabilities, terrestrial laser scanning has recently proved a revolutionary technique for high accuracy, 3D mapping and documentation of physical scenarios and man-made structures. Particularly, this is of great importance in the underground space and tunnel construction environment as surveying engineering operations have a great impact on both technical and economic aspects of a project. This paper discusses the use and explores the potential of laser scanning technology to accurately track excavation and construction activities of highway tunnels. It provides a detailed overview of the static laser scanning method, its principles of operation and applications for tunnel construction operations. Also, it discusses the planning, execution, data processing and analysis phases of laser scanning activities, with emphasis given on geo-referencing, mesh model generation and cross-section extraction. Specific case studies are considered based on two construction sites in Greece. Particularly, the potential of the method is examined for checking the tunnel profile, producing volume computations and validating the smoothness/thickness of shotcrete layers at an excavation stage and during the completion of excavation support and primary lining. An additional example of the use of the method in the geometric documentation of the concrete lining formwork is examined and comparisons against dimensional tolerances are examined. Experimental comparisons and analyses of the laser scanning method against conventional surveying techniques are also considered.

No MeSH data available.


Related in: MedlinePlus