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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

View of the formwork from the north portal abutment. The location of TLS stationing in the south abutment is denoted by a circle (a); The raw point cloud data recorded from the south portal abutment (b).
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f14-sensors-12-11249: View of the formwork from the north portal abutment. The location of TLS stationing in the south abutment is denoted by a circle (a); The raw point cloud data recorded from the south portal abutment (b).

Mentions: After tunnel excavation has been completed a permanent lining is installed. In the case of Tempi T1 tunnel, permanent support consists of cast in-situ concrete lining using formwork. The concrete lining process involves the use of a 12 m long metallic arch formwork travelling along the tunnel on temporary rails (Figure 14(a)). After the form is set into position a timber bulkhead is constructed at its open ends and concrete is pumped through openings (hatches) in the sides and top. Once lining is complete and concrete is sufficiently solidified, the form moves 12 m ahead and the same process is repeated.


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

Gikas V - Sensors (Basel) (2012)

View of the formwork from the north portal abutment. The location of TLS stationing in the south abutment is denoted by a circle (a); The raw point cloud data recorded from the south portal abutment (b).
© Copyright Policy
Related In: Results  -  Collection

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

f14-sensors-12-11249: View of the formwork from the north portal abutment. The location of TLS stationing in the south abutment is denoted by a circle (a); The raw point cloud data recorded from the south portal abutment (b).
Mentions: After tunnel excavation has been completed a permanent lining is installed. In the case of Tempi T1 tunnel, permanent support consists of cast in-situ concrete lining using formwork. The concrete lining process involves the use of a 12 m long metallic arch formwork travelling along the tunnel on temporary rails (Figure 14(a)). After the form is set into position a timber bulkhead is constructed at its open ends and concrete is pumped through openings (hatches) in the sides and top. Once lining is complete and concrete is sufficiently solidified, the form moves 12 m ahead and the same process is repeated.

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