Determination of monitoring systems and installation location to prevent debris flow through web-based database and AHP

Various monitoring systems have been applied to warn regarding debris flow; however, the information regarding the selection sensors and determination of the installation area is deficient. The objective of this paper is to propose an appropriate monitoring system to prevent debris flow and a method for determining the installation location. A web-based database is used to find the applied frequency of sensors, and the sensors are grouped into eight parts with consideration of the performance, including rainfall, debris flow velocity, displacement, fluid pore pressure, ground vibration, image processing, impact force, and peak flow depth. Through the statistical technique, the rain gage and geophone sensors are revealed as hugely selected sensors among various systems to provide an alarm. The analytic hierarchical process (AHP) is also used to analyze experts’ opinion through pairwise comparison with consideration of eight geotechnical parameters, including the fine content, void ratio, shear strength, elastic modulus, hydraulic conductivity, saturation, soil thickness, and water content. The weighting factors of every parameter are deduced through AHP and the installation area is chosen with calculated values using the weighting factor. The suggested analyses are helpful to select appropriate sensors and determine the installation location of a monitoring system.