Picture this scenario: A construction crew arrives ready to begin work only to find that several stubs are located in the wrong place on a freshly poured concrete floor. The error means that thousands, maybe millions of dollars of shop-fabricated steel pipe and other components sit in the laydown yard until concrete is either jackhammered away and stubs are moved to the correct location, or piping modifications are made to address the misalignments. Either way, time and money are lost.
Scenarios like these can move a project budget into the red, idle highly paid trades and put projects well behind schedule.
Advanced Tech Solutions
Thanks to innovative augmented reality (AR) technology, many of those headaches may soon be a thing of the past. AR technology can provide real-time visualizations of structures, piping, conduit stub-up location and all other types of infrastructure. It is quickly transforming the planning, communication and execution of a wide range of construction activities.
These tools can be used both indoors on retrofit projects or outdoors on greenfield sites by overlaying digital 3D models and project data onto the physical site, using mobile devices like smartphones, tablets or AR headsets. A number of use cases are emerging, but the primary benefits are reducing costly schedule delays and damage while improving safety. Features include:
- Comparison of 3D models in real time to align with field conditions as an instant as-built, to detect discrepancies early before final placement.
- Visualization of hidden infrastructure and utilities behind walls or underground, allowing crews to avoid accidental strikes.
- Remote team collaboration through sharing of AR views of the construction site, thus streamlining communication and accelerating decision-making.
Trimble SiteVision technology is being demonstrated on selected Burns & McDonnell project sites to visualize project progress and detect design changes or conflicts. The application enables site personnel to access 3D models from the cloud and visualize them through mobile devices. A global navigation satellite system (GNSS) antenna is used to georeference the model using global positioning system (GPS) data in outdoor environments for centimeter-level accuracy. QR code markers are used to anchor 3D models for use indoors.
Augmented reality technology relies on the accuracy of the 3D model. With this advanced tool available for real-time field verification, design models can be updated to reflect construction progress instantly. By maintaining precise model accuracy with tolerances of a centimeter, the likelihood of errors and rework is greatly reduced. For example, if a flange or pipe support is misaligned, AR displays its digital position on-site, allowing any corrections to be made before installation, eliminating the need for later rework.
The tool can easily integrate with lidar (light detection and ranging) technology, a separate and powerful tool that is commonly used to perform site verification.
AR can augment the process as a simple, lightweight application that may be operated by many users.
When a complex foundation is being formed that contains a large number of anchor bolts and electrical embeds, the AR tool can be used to quickly verify — before any concrete is poured — that all are placed precisely in the correct locations.
If AR reveals that anything is misaligned, a highly specialized individual may come in with lidar technology to perform a 3D laser scan of the area, creating a point cloud for millimeter-level accuracy and verification.
With many more pipe and steel components fabricated in shop environments to reduce construction labor hours, and delivered to the site ready for installation, it is vitally important that accurate dimensions are available from the job site.
The time and cost savings resulting from the use of this next-level technology is likely to soon make it the gold standard for safer and more efficient construction projects.
Construction project spending has reached 13% of global GDP, yet productivity still lags. A mix of technology and proper planning can alleviate this issue.
