Noise effects on Monitoring of Rock Slope Deformations by a High-Resolution borehole Tiltmeters in an Open Pit Limestone Mine

A high-resolution borehole tiltmeter introduced in this paper, is a diagnostic tool for a rapped assessment of limestone slope stability. It is used to measure the deflection of rock slope in an open pit limestone mine. The highresolution tilt-meter measurements are disturbed by different types of noises which arise from different sources. Tilt-signal is affected by various cultural and natural noises. The surface noises, environmental noises, earthquakes and the earth tide are significant, as well as the noises due to quarrying operation. Among the noises due to quarrying operation, the ground vibration due to blasting with ANFO explosives is of importance. Environmental noise sources consist of ground temperature, rainfalls, change of water table and so on. The noise effects must be separated from the tilt data to obtain the movements being in question. For this reason the noise elimination procedure is discussed by presenting the tilt-time records obtained at the toe line of the operating pit. Subsequently, the time-dependent behavior of limestone slopes remained after the excavation bench-cut excavation is analyzed to make clear the significant influence of rainfalls on tilt data.

Keywords:

High-Resolution Tilt-meter , Tilt signal , ground vibration , cultural noises , natural noises , environmental noises , quarrying operation