The Helical segmental lining is an invention in tunneling industry wherein segments are designed in helical shape that are connected by interlocking system. The proposed helical tunnel lining method allows for segment erection and excavation to be completed concurrently and continuously by Tunnel Boring Machine (TBM) which will result in increasing the tunneling speed. The segments have tongue projection on the two trailing sides (circumferential and radial) and similar groove recess in the opposite two leading sides. This forms a tongue-and-groove joint at both circumferential and radial joints. The system allows for optional post-tensioning (PT) strand to be inserted into the leading circumferential side of the segments. The optional PT strand is fitted into a continuous groove located at the leading circumferential side of the segments. The system has solutions for the alignment curves and turning of the helical segmental lining, sealing of the system as well as terminating the strand and beginning another due to limitation of the strand length. The method is eliminating bolt connection between segments and increase tunnel advancement rate. The system allows for using typical (identical) segments.

The Helical segmental lining is an invention in tunneling industry wherein segments are designed in helical shape that are connected by interlocking system. The proposed helical tunnel lining method allows for segment erection and excavation to be completed concurrently and continuously by Tunnel Boring Machine (TBM) which will result in increasing the tunneling speed. The segments have tongue projection on the two trailing sides (circumferential and radial) and similar groove recess in the opposite two leading sides. This forms a tongue-and-groove joint at both circumferential and radial joints. The system allows for optional post-tensioning (PT) strand to be inserted into the leading circumferential side of the segments. The optional PT strand is fitted into a continuous groove located at the leading circumferential side of the segments. The system has solutions for the alignment curves and turning of the helical segmental lining, sealing of the system as well as terminating the strand and beginning another due to limitation of the strand length. The method is eliminating bolt connection between segments and increase tunnel advancement rate. The system allows for using typical (identical) segments.

The Helical segmental lining is an invention in tunneling industry wherein segments are designed in helical shape that are connected by interlocking system. The proposed helical tunnel lining method allows for segment erection and excavation to be completed concurrently and continuously by Tunnel Boring Machine (TBM) which will result in increasing the tunneling speed. The segments have tongue projection on the two trailing sides (circumferential and radial) and similar groove recess in the opposite two leading sides. This forms a tongue-and-groove joint at both circumferential and radial joints. The system allows for optional post-tensioning (PT) strand to be inserted into the leading circumferential side of the segments. The optional PT strand is fitted into a continuous groove located at the leading circumferential side of the segments. The system has solutions for the alignment curves and turning of the helical segmental lining, sealing of the system as well as terminating the strand and beginning another due to limitation of the strand length. The method is eliminating bolt connection between segments and increase tunnel advancement rate. The system allows for using typical (identical) segments.

The Helical segmental lining is an invention in tunneling industry wherein segments are designed in helical shape that are connected by interlocking system. The proposed helical tunnel lining method allows for segment erection and excavation to be completed concurrently and continuously by Tunnel Boring Machine (TBM) which will result in increasing the tunneling speed. The segments have tongue projection on the two trailing sides (circumferential and radial) and similar groove recess in the opposite two leading sides. This forms a tongue-and-groove joint at both circumferential and radial joints. The system allows for optional post-tensioning (PT) strand to be inserted into the leading circumferential side of the segments. The optional PT strand is fitted into a continuous groove located at the leading circumferential side of the segments. The system has solutions for the alignment curves and turning of the helical segmental lining, sealing of the system as well as terminating the strand and beginning another due to limitation of the strand length. The method is eliminating bolt connection between segments and increase tunnel advancement rate. The system allows for using typical (identical) segments.