Introduction of Conventional Tunneling cutting-edge technologies
The Cutting-Edge Approach
More than 100 years of Obayashi’s engagement in tunnel construction, 50 years since the indispensable NATM (New Austrian Tunneling Method) was introduced in Japan ---- over those years, tunnel technology has improved dramatically. With the experience of more than 600 projects around the world, Obayashi is committed to technical research and development, combining our predecessors’ expertise with the latest technologies.
(Available only in Japanese.)
Exploration Technology
Non-core drilling geological exploration ahead of the tunnel faceTunnel Navi®
Prevents collapse and deformation by predicting the geology ahead of the tunnel face. Exploration costs can be reduced by 90%.
Geological prediction ahead of the tunnel face using hydraulic down-the-hole hammerWater Hammer Navi®
Quick geological exploration 150m ahead of the tunnel face.
Seismic Prediction Method Ahead of Tunnel FaceWater Hammer V-Checker®
Early identification of geologic risk ahead of face using striking vibration of advanced boring.
Prediction and countermeasures for water inflow in tunnelsSystem for water inflow detection ahead of tunnel face and countermeasure selection
Detects fracture and aquifer zones and selects drainage measures to prevent sudden water.
Prediction ahead of tunnel faceDetection of water inflow zone by elastic wave exploration
Prevents collapse by predicting large and sudden water inflow. Minimizes interruptions to excavation work.
Evaluation of heavy metals in tunnelsHeavy metal evaluation with cuttings of non-core drilling
Quickly collects samples for heavy metal and evaluates them in a short time.
Observing the inside of a boreholeSimple intra-hole observation camera
A simple and inexpensive way to observe the inside of a borehole.
Tunneling Technology
Remote erection technology of steel supports for tunnelsQuick Telector®
Improve safety and productivity by eliminating work directly below the tunnel face.
Remote shotocrete technology for tunnelsShotcrete system that synchronizes with the contours of the tunnel wall
Simplifying and Improving the Quality of Shotcrete Work in Tunnel Shoring Technology.
Dedicated remote rock bolting machine in tunnelsRoboltus
Remote operation improves safety and saves labor.
Improving the safety and productivity of mucking for tunnelsSlideloader
Aiming for remote and automated operation with improved operational operability.
Lightweight steel pipes for tunnel forepilingAGF-Toughlight®
Improving work efficiency in forepiling by lightweighting steel pipes using high-strength steel materials.
A drive system for stretchable conveyors for tunnelsNon Cut Drive
Eliminates the need for belt cutting, shortening construction period and improving on-site productivity.
Ground preloading methodContact Bag Method®
Prevents subsidence caused by tunnel excavation with cloth bags filled with ultra-rapid setting mortar.
Ground stabilization methodFooting reinforcement using stepped steel pipes
Increases the bearing capacity of the tunnel footing and prevents subsidence.
Stability measures for tunnel faceTough Tube®
Cost-effective tunnel face reinforcement using high strength steel pipe anchorage.
Continuous belt conveyor system with quick extensionALCS®
For rapid tunnel construction without interrupting the excavation work.
Lining Technology
Concrete lining for tunnelsNeuro-Crete Neo®
High-flow and self-compacting properties without increasing cementitious contents.
Automatic lining concrete placing systemContinuous placing system with an automatic telescoping delivery hose
Reduces labor and improves quality of the lining operation.
Labor saving in lining concrete workFully Automatic Traveling Form Setting System
Reduction of workforce for lining to 1/3 of conventional ones.
Automatic expansion system for long waterproof sheets that conform to the shape of wall surfacesLong-span slack sheet tensioning system
Follows the unevenness of the tunnel wall surface for high quality construction.
Labor saving gable formwork during tunnel liningLabor Saving Bari System
Labor saving formwork fixing work for tunnel lining, ensuring concrete quality and safety.
Anti-adhesive material for tunnel lining jointsSeparate-Coat®
Reduces deficient risk such as cracks and spalling at joints.
Middle-fluidity lining concrete for tunnel liningSmooth-Crete
For high quality tunnel lining with high-flowing concrete.
Concrete lining for tunnelsHigh-compactable concrete
High quality and economical tunnel lining concrete.
Equipment for tunnel liningTelescopic-type traveling formwork with continuous belt conveyer passing through the inside
Improves tunnel lining quality by lengthening the curing time while allowing concurrent tunnel excavation and lining.
Equipment for tunnel liningRail-mounted mobile formwork vibrator
For high quality, economical tunnel lining.
High-performance curing system for tunnel liningMoist-Cure®
Constructs high-quality and highly durable tunnels by preventing cracks during concrete lining curing.
Environmental technology
Dust reduction methodTravel Clean Curtain®
For quick and dramatic improvement of the work environment in the tunnel.
Noise reduction technology for tunnel blastingBlast Silencer®
Hybrid blasting sound countermeasure technology for low-frequency sounds and audible sounds, utilizing the resonance phenomenon and the sound absorption effect.
Measurement Technology
Wireless strain measurement system for steel support in tunnelsHaka-Router®
Real-time strain monitoring ensures a safe working environment.
Tunnel Face Collapse Detection SystemRockfall Finder®
Detects early signs of face collapse.
Labor-saving and manpower-saving of measurement work for tunnels3D cross-sectional measurement system using light-plane-intersecting method
Collaboration between human and robot improves the efficiency of measurement work.
Detection technology for loose rocks in tunnelsTunnel floating rock detection technology using lasers
Prevent disasters caused by rockfall near the tunnel face.
Remote operation for tunnel profile measurement and monitoring work safety at tunnel facesTunnel Profile Measurement and Monitoring UGV
Unmanned directly under the face to ensure safety and control quality.
Labour-saving technology for rock bolt pull-out tests in tunnelsLightweight rock bolt pull-out test system
We are working on lightweighting the rock bolt extraction testing machine and automating the measurement and report generation process.
AI application to monitor real-time progress of work inside tunnelsCyclEye®
Improving productivity by analyzing image and audio data of tunnel face work conditions.
Real-time AI-based system for determining the status of face work in tunnelsTunnel excavation status visualisation system using current value AI analysis
Automatic determination of tunnel excavation status based on power current value fluctuations.
Displacement measurement ahead of tunnel faceTwo-direction preceding displacement meter
Measure underground displacement caused by excavation and monitor impact on nearby structures.
Measurement of settlement ahead of tunnel facePreceding displacement meter
Prevents collapses by predicting face instability in advance.
Ground displacement measurementThree-axis ground displacement gauge
Monitors the effects of tunnel faces passing through nearby structures.
Measurement of tunnel invert heavingInvert Displacement Gauge®
Measures heaving in the tunnel invert and allows for corrective measures.
Face evaluation of tunnels using AITunnel Face Evaluation by AI
High-precision determination of seven evaluation items related to tunnel face based on images of tunnel face.
AI is used to ｊudgement the seven rock types in the tunnel excavated rockRock Type Judgement System
Highly accurate determination from photographs of rocks.
CIM incorporating predictions of the geology ahead of the face of tunnelsTunnel predictive CIM
Integration of design, construction and maintenance data.
Information management technology using 3D modelsCIM (Construction Information
Modeling/Management)
Improves productivity and maintenance management by visualizing the construction process and streamlining the integrated information.
Renovation
Concrete surface protection and reinforcement methodSmooth Board Method®
Reinforces the surface of the tunnel lining with cement boards.
Spray-on repair and reinforcement methodJOT’S-Crete®
Quick, economical repair and reinforcement with fiber-reinforced mortar spray.
Back-fill grouting methodSpace Pack Method®
Fills the void behind the tunnel lining with plastic injection material.
Back-fill grouting method for tunnel lining back cavitySpace Pack Construction Method®（carbon-negative type）
Tunnel renewal technology that reduces CO2 emissions by up to 250%.
Renewal while the tunnel is in serviceRepair-Arch®
Safe renewal of arch lining concrete while securing traffic in road tunnels.
