2019 Volume 75 Issue 2 Pages I_133-I_138
As an initial survey method after earthquake disasters for mooring facilities, utilization of unmanned aerial vehicles (UAV) was examined. Although it is possible to evaluate the displacement by analyzing the captured image taken by UAV, it is important to set control points to ensure accuracy. In large-scale earthquakes, the residual displacement of the quay wall to the sea must affect the large area of the back ground, and the control points whose coordinates have been measured before the earthquake should also be moving. Therefore, it is necessary to newly set the control points and measure the coordinates after the earthquake for the accurate evaluation, but it is difficult if we cannot enter the facility by tsunami warning. In this study, the limited use of control points after the earthquake was assumed in the image processing. The influence of arrangement of control points on the measurement accuracy of residual displacement in mooring facilities was evaluated in such a situation.
