Laboratory Testıng of Effects Caused By Landslıdes Trıggered By Earthquakes Through Utılızıng Fıber Optıc Methods

Abstract

Landslides are one of the most destructive natural disasters in the world and Turkey, causing significant loss of life and economic problems. There are many different applications available today for monitoring landslide and mass movement hazards, such as inclinometers, tiltmeters, extensometers, and ground-based surface digital measurement systems (such as radar, laser scanners, electro-optic, total station, etc.). However, these methods have their advantages and disadvantages and are mainly used to determine and monitor the deformations that occur, rather than being applied to simultaneous monitoring systems, because their temporal resolution depends on the repetition periods. Fiber optic systems are superior to other methods due to their easy and high-speed data transfer, small size and lightweight, sensitivity to unit deformation and temperature changes, ability to work with a wide bandwidth, resistance to environmental and electromagnetic effects, low cost, and ability to perform simultaneous monitoring. These technical features are also important for early warning systems.

This thesis aims to develop a reliable monitoring system for landslides by simultaneously monitoring the movement on the sliding surface caused by any triggering mechanism through the deformations in the fiber optic cable, independently of the lithological unit and failure types, by setting up a landslide simulator in a laboratory environment. To this end, the deformations caused by the dynamic triggering mechanisms produced by the shaking table set up in the laboratory were studied to enable testing of the sensitivity of the fiber optic cables from different perspectives. As a result of these studies, sensitivity analyses considering the selection of the appropriate fiber optic cables for being used in a real-time landslide site were performed. These measurements were validated with those deformation measurements obtained by using a potentiometer in the laboratory environment for evaluating the reliability of the system.