The latest version of Trimble Access, v2021.20, introduces new scanning functionality and 3D design visualization for tunneling users. Trimble Access Tunnels v2021.20 was released November 10, 2021.
The latest version of TBC v5.60, introduces several new functions and enhancements to the existing toolset. TBC Tunneling v5.60 was released November 15, 2021.
Data Prep? No Problem with the Multiple Set Outs Tool
One of the primary tasks for tunnel survey and construction professionals is to set out key construction locations such as blast holes, rock bolts, anchors, and many others. Preparing this information for stake out in the field is crucial for ensuring the success of the survey crew. Trimble Business Center introduces a new tool for automatically creating multiple set out points reducing time for office technicians to prepare design data for the field. Prior to this feature, set out points needed to be created individually, one at a one. With TBC v5.6, creating multiple set outs is a breeze.
Enhanced Tunnel Analysis and Reporting
The most important deliverable for tunnel surveyors is as-built reports to provide quality control and verification of the construction activities. TBC provides a wide range of customizable reports for survey data. With this new version of TBC Tunneling, the as-built report has been enhanced to include key statistics on survey data such as over and underbreak volumes, maximum out of tolerance points, and the ability to remove outlier points. The outlier feature is key for removing ‘noisy’ data such as machinery, equipment, and other non-tunnel features from the as-built report providing more accuracy on the end deliverable.
TBM Tunnels and Scanning
During TBM (Tunnel Boring Machine) construction, surveyors are tasked with creating as-built reports on the final position of TBM rings and subsequently the as-built center line of the tunnel. This is important for designers to ensure other elements that will be installed in the tunnel, such as rail tracks, electrical conduits, piping, are placed in the proper location relative to the finished tunnel structure. TBC v5.6 introduces a customizable TBM as-built report which includes a variety of statistics on the finished TBM ring as well as a best-fit routine to calculate the final position of the tunnel alignment. This data is automatically translated into a series of 3D points which can be used with TBC’s best-fit line tool to create a finished as-built alignment. This function can be used with point cloud or total station data. The resulting deliverables provide an out-of-the-box report for stakeholders on the TBM ring positions and streamline the process for providing design and engineering team with as-built CAD data.
Back in the Field: Visualize Tunnel Designs in 3D in the Context of Scan and Survey Data
It can be difficult to visualize a tunnel design while in the field. Trimble Access Tunnels now shows tunnel designs (TXL) in 3D making it easier to perform fast infield verification of construction processes with scan and total station data. In conjuntion with the scan inspection tool, perform shotcrete or excavation checks in full 3D while in the field in 5 minutes.
Cut Scanning Time in Half With New Half-Dome Scanning
For tunnel surveyors, efficiency is everything. While laser scanning offers high quality, comprehensive data, reducing collection time is a high priority for underground surveyors. Typically, tunnel surveyors will only require a scan in the forward direction, collecting as-built data of newly excavated areas, while the data behind them is irrelevant. The requirement to perform a Full Dome scan (scanning 360° around) can be time consuming, especially when only half the data is needed.
With the release of Trimble Access v2021.20 mine surveyors can now limit the focus of their SX12 scan to the forward direction only by utilizing the new Half-Dome Scan option. This new scanning method provides a critical boost for productivity, cutting scanning time by 50%. As the graphic above suggests, you can set the direction of your scan by aiming toward the face of the tunnel advance, and then scan only that which is in front of you. This time savings enables you to be far more efficient, both in the field and in the office. By capturing only that data which matters most to your workflow, you can save precious time in the field and make decisions in real-time. Back in the office with TBC, the more focused dataset reduces processing time and provides a streamlined point cloud, perfect for fast delivery to stakeholders.
Making 3D Tunnel Meshes More Accurate
Every tunnel project is different. Whether it is a TBM, SEM, or other type of tunnel construction method, surveyors need to create accurate as-built reports. In TBC v5.60, the 3D as-built mesh has been enhanced to support a closed vs. open option. For projects where the tunnel is being constructed in stages (top heading, invert, etc.), the open mesh is extremely valuable for accurate volume and over/underbreak analysis as it removes the tunnel floor from the analysis. For closed meshes, TBM tunnel as-built can be visualuzed properly with no openings in the mesh.
To learn more about how the Trimble Tunnel survey system can benefit you on your next underground project, fill out our contact form here.