RESEARCH ON THE APPLICATION OF CONSTRUCTION HISTORY DATA OF GRAB DREDGER TO FINISHED FORM MANAGEMENT FOR FLOOR DIGGING

Abstract

 The present finished form measurement for floor digging is mainly conducted by single beam or multibeam echo sounding. However, echo sounding takes considerable time for setting of equipment, navigation, and data processing. This study aims to improve work efficiency by utilizing the construction history data of a grab dredger for the finished form measurement. The location and depth of floor digging are estimated at each grid by the horizontal coordinate of the top of a crane boom and the length of hoisting wire rope. Field experiments are carried out at three different construction sites of floor digging to compare the finished form measurement between construction history data and echo sounding. The result shows that the finished form measurement by construction history data is in good agreement with echo sounding and the design depth. At over 90% of all the grids with 1 m by 1 m size, the finished form measurement by construction history data satisfies the shape control criteria for floor digging.