IN-SITU CALIBRATION OF BOREHOLE SHEAR STRAINMETER AT TAIAN STATION
泰安台钻孔差应变观测的实地标定

On the basis of operating principle and the observations by borehole shear strainmeter and by use of theoretical earth tide,a new method for in-situ calibration of borehole shear strainmeter at Taian station is presented.The results show that the data of shear strain 2 are reliable because the component 2 and 4 of shear strainmeter work normally.The calibration coefficients of component 3 are considerably fluctuant.The data of shear strain 1 and 2 agree with their theoretical values on the whole after in-situ calibration.The shear strain observations have to be calibrated in different periods of specific issues,as the calibration coefficients change with time.