High-range and high-precision tensiometer based on fiber grating and use and saturation method thereof

Abstract

The invention provides a high-range and high-precision tensiometer based on a fiber grating and a saturation method thereof. The tensiometer comprises a high air inlet value pottery clay head, whereinthe high air inlet value pottery clay head is arranged in an upper nested ring and is directly contacted with soil to establish hydraulic connection, an elastic membrane sheet is arranged at the upper part of a lower base, a water storage cavity is formed in the upper nested ring, in a gap between the elastic membrane sheet and a high air inlet value pottery clay plate, and a pressure measuring grating is fixed on the elastic membrane sheet through two grating fixing columns which are symmetrically arranged. The tensiometer is suitable for long-term monitoring and can also be applied to a region affected by a magnetic field, the fiber grating is adopted as a sensing strain element, the tensiometer is easily expanded to a positive pressure part, the height of the water storage cavity is reduced, the measuring range of the tensiometer is improved, an 'O'-shaped sealing ring is arranged, the interference of external stress is reduced, a temperature compensation fiber grating is arranged,and the influence of temperature difference fluctuation of the surrounding environment of the soil body on a measurement result can be avoided; the saturation method of the tensiometer is simple to operate and good in saturation effect.

Description

technical field [0001] The invention relates to a fiber grating sensing instrument, in particular to a fiber grating-based high-range and high-precision tensiometer and a saturation method thereof. Background technique [0002] The shallow soil in nature is in an unsaturated state. Due to the existence of pore air in unsaturated soil, there is suction in the soil, and suction is a core factor affecting the properties of unsaturated soil. Therefore, suction measurement becomes an unsaturated A core issue in the study of soil mechanics. In the existing measurement technology, there are many methods for suction measurement, including direct methods, such as tensiometer method and axis translation technology; indirect methods, such as filter paper method. Among these methods, the axial translation technique is generally suitable for indoor tests, the filter paper method is greatly affected by the external environment, and requires a high operating level of testers, and the tens...

AI Technical Summary

Problems solved by technology

However, the design of most tensiometer saturation devices is complicated, and the use process is time-consuming and laborious; some saturation devices even have fatal defects such as air leakage and water leakage, which affect the saturation effect of the tensiometer

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