DEVELOPMENT OF THE SYSTEM TO MEASURE THREE-DIMENSIONAL DEFLECTION OF LARGE CONCRETE STRUCTURES USING A LASER DIODE AND A QUADRANT PIN PHOTO DIODE

In this study the system to measure three-dimensional static and dynamic deflection with 0.5mm accuracy from the distance of 50m to 150m away using a laser beam has been developed. The measuring system consists of two sets of theodolite with the launcher of a laser and the device which receives the laser. The system enables to measure the deflection along z axis as well as x and y axes. The deflection of a concrete arch dam caused by solar heat during a daytime is measured by this system, and the obtained results were discussed.