This article describes the practical aspects of creating an effective fiber-optic system of monitoring the load-bearing constructions of engineering structures operating in the Far North. Taking into account the actual operating conditions on a real object, the design of the measuring device was developed; fiber Bragg gratings were used as sensitive elements of fiber-optic strain sensors and a temperature compensator. Taking into account the design parameters of the researched pile foundation, a spatial topology and a switching circuit for measuring devices were developed, and the monitoring process was launched. It is shown that the developed system is an effective tool for monitoring the stress-strain state of the monitored object online.