Inclinometer tests are carried out in order to locate the depth at which the slip surface is located and for monitoring possible horizontal ground movement, especially after heavy rainfall. Inclinometer casings are installed inside drilled boreholes. These are plastic pipes with 70 mm external diameter and 10 mm thick, that have four internal grooves arranged in equal distances at the inner perimeter of the casing. The inclinometer casings are installed inside the drilled borehole down to the desired depth and the space between the walls of the borehole and the casing is grouted using appropriate grout mixture. The grouting is carried out from bottom to top of the borehole using a flexible water leveling plastic hose that for this purpose is lowered to the bottom of the borehole. The type of grout mixture varies depending on the ground conditions in each borehole. On the surface, in order to protect the casings, a protective head is installed, with a cap with a lock at the top.
The inclinometer tests are carried out with a GEOCONSULT Ltd. owned inclinometer manufactured in the USA by SLOPE INDICATOR. The main parts of the equipment are the probe that is lowered inside the borehole, the digital readout unit and the control cable that connects the probe to the digital readout unit. The probe has micro sensors at the top and the bottom, that measure with grate accuracy angular divergence between them. The reading is carried via the control cable to the digital readout unit at the surface. The probe has wheels at the top and the bottom, that are placed in the grooves of the casing, and connected via the control cable it is lowered inside the borehole. The readings are taken every in 0.50 m vertical increments. Comparing the readings of consecutive inclinometer tests, that are carried out in regular intervals, possible ground horizontal micro-movements are recorded in reference to depth.