Boldly Pioneering SHM
HART Rail - In Honolulu Hawaii, SMS is providing a new fiber optic sensor acoustic technology that allows 20-years of monitoring. This was made as a response to HART having three tendon failures on this new bridge or guideway. “Engineer: Failed Tendons Could Lead to Catastrophic Collapse of Rail Line” https://www.khon2.com/always-investigating/hart-wants-deeper-look-into-critical-rail-construction-problems/
In this monitoring situation, a traditional acoustic sensor would require two to three times the number of sensors, especially on a noisy rail line, which would mask a wire break on a typical system. And a typical monitoring system would require tens of power drops due to voltage drops. Electric sensors must have short cables because the DC voltage signal decays. SMS’s only used 3 power drops and less than 6 miles of fiber optic cable to cover the 6.2 miles of concern. The overall cost of the system was much less than an electrical based system. Newly developed installation technologies will allow in faster and lower-cost solutions for projects like HART.