VIBRATION MONITORING CASE STUDY:
L.A. Subway Expansion Project
Vibration Monitoring Beneath Beverly Hills
Constellation Boulevard. Century Plaza. Avenue of the Stars. Rodeo Drive. When tunneling beneath such American icons, the need to protect them from harm takes on a heightened level of importance.
So the geotechnical engineering team at Analysis and Solutions Consultants (ASC) turned to Inzwa to provide vibration monitoring of station sites at these high-profile locations during a five-year excavation and tunneling subway expansion project. They chose the Veva III for four key reasons:
Ease of installation
No external power required
Easy and fast configuration & activation
Easy data acquisition and display
Inzwa vs. Traditional Vibration Monitoring Systems: Fast and Easy Installation
Unlike traditional geophone-based systems that require cobbling several external components together, the Veva III vibration monitors came ready to install and activate right out of the box. “You just take the device, drill into the wall, and it’s done,” ASC's lead engineer said. “It took about five minutes.”
Inzwa vs. Traditional Vibration Monitoring Systems: No Power Challenges
The long battery life of the Veva III also helped ASC to sidestep another drawback inherent to traditional systems: where to get power. Several vibration monitoring site locations had no ready power source, and being below ground made solar panels not an option. Traditional systems in these locations might have required approaching building owners and negotiating for access to power. “All these problems were not an issue with Inzwa,” ASC's lead engineer explained. “No external power source was needed.” With its robust integrated Lithium battery and the project’s monitoring requirements, battery life was estimated to be up to a year or more.
Inzwa vs. Traditional Vibration Monitoring Systems: Up and Running in Minutes
Traditional geophone-based systems often require several steps and multiple hours to set up, test, connect and retest. “The back-end work [to configure and activate] legacy systems, there are like four or five steps involved in setting up and displaying the data,” ASC's lead engineer explained. “Here, with Inzwa, you basically don’t need to do any of that. You just turn it on and that’s it. Also, the backend work in setting up alarms and notifications is minimal.”
Inzwa vs. Traditional Vibration Monitoring Systems: Huge Time Savings
All told, Inzwa saved ASC significant labor hours vs. traditional systems. “We can set up a legacy system in half a day, with another half a day for configuring,” their lead engineer estimated. “With Inzwa, it took about 15 minutes.”
Results: Inzwa Monitoring for the Long Haul
ASC installed a total of eight Veva III vibration monitors at various sites throughout the 1.5-mile-long project. With annual calibrations, these devices are slated to provide continuous monitoring for the life of the project, projected to be five years or more.