Review of Inclinometer Errors and Provide Correction Methods for Bias shift Error and Depth Position Error of the Probe

Abstract

The inclinometer is now widely used to measure ground movements and has been used successful in projects associated with proper planning, quality tools, ideal installation of inclinometer casings, committed reading, correct processing of data and intelligent interpretation. When using an inclinometer, a wide range of random or systematic errors can occur. According to previous experiences, in these situations, interpreting data becomes difficult and erroneous conclusions may be drawn about the extent, location, and direction of motion. Errors may be due to equipment defects, improper usage, as well as known system limitations or errors. In this study, the author has reviewed the errors in inclinometer systems. Furthermore, by performing tests on the inclinometer casings of Darian Dam, numbers of common errors were presented such as data bias error, rotation error of sensor axis, and probe positioning error in depth, and in addition, the author tried to find out how to correct the incorrect data. The author also describes the correction method of bias error introduced by Mickelson and provides a method for correcting the depth error of the probe positioning. Based on the proposed method, instead of calculating the amount of correction values due to the depth position error of the probe for each measured dataset, the base data (initial reading) are modified with the relationships provided by the author, and then, the displacements were calculated again. The ability of the proposed method was tested by creating an artificial depth error in one of the inclinometers of Darian Dam, as a result of which the mentioned error was corrected the best.