Field immediate calibration method for earth pressure cell

Abstract

The invention discloses a field immediate calibration method for earth pressure cells. The technical scheme is as follows: when calibration is conducted, a computer, data connecting wires, a stain acquisition instrument, a sandbox, a bearing plate, a plurality of weights and earth pressure cells to be calibrated are brought to a field with earth pressure that needs to be calibrated, the earth pressure cells are buried in the center of the sandbox through undisturbed soil and connected with the strain acquisition instrument, the surface of the sandbox is flattened by the undisturbed soil in the field and is covered by the bearing plate, the bearing plate is loaded step by step, micro strain values are acquired by the strain acquisition instrument every time, acquired micro strain values and corresponding loading values are inputted to the computer, the computer adopts a regression formula for fitting a straight line, and the accurate relation between the strain and the stress of the earth pressure cells is finally obtained. According to the invention, the computer is adopted for data processing, and the quantitative relation between an input quantity and an output quantity can be obtained intuitively and rapidly; when the calibration is completed, the earth pressure can be measured by calibrated earth pressure cells, so that the calibration is convenient and accurate.

Description

technical field [0001] The invention relates to an earth pressure cell calibration method. Background technique [0002] In the pressure monitoring of geotechnical engineering, the earth pressure cell is mostly used as the pressure sensor, and the earth pressure cell needs to be calibrated after being used many times before it can be reused. The existing calibration method is to use the gas pressure generated by the pressure device for calibration, and use the endpoint method to determine the sensitivity coefficient. However, there are two main problems in this method: (1) The coefficient determined by the endpoint method is too simple, which is prone to test errors; (2) There are differences between the gas medium and the test soil (or sand), because the internal structure materials of the sensor have different Medium compatibility. The sensitivity coefficients in different media are not the same. The sensitivity coefficients obtained in gas or liquid media should not be d...

AI Technical Summary

Problems solved by technology

[0004] In order to solve the technical defects of cumbersome operation and long calibration time in the above earth pressure cell calibration method, the present invention proposes an on-site instant calibration method for earth pressure cell

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