Fiber Bragg Grating Earth Pressure Gauge

Model：ZZ-FBG-SP5

1、Summary

The Nanjing Zhunzhi ZZ-FBG-SP5 fiber optic grating earth pressure gauge is a sensor used to measure soil stress or soil structural pressure. Two flat plates are welded together along their circumference, leaving a gap between them. The function of soil pressure is to press the two plates together, so that the pressure sensor in the plate groove can sense the pressure and measure the pressure value of the soil from the surface. This is only true when the deviation of the sensing plate from the zero position is kept to a minimum, so the robustness of the earth pressure gauge is important。

Many research experiments (such as Dunnicliff's 1988 report) have shown that introducing a plane stress gauge into soil will affect the change in soil stress field, depending on the relative stiffness of the soil pressure gauge to the soil, as well as the aspect ratio, that is, the ratio of the width of the soil pressure gauge to its thickness. Thick soil pressure gauges can better change the stress state of the soil than thin ones. Therefore, using a thin rigid soil pressure gauge is the best option。

2、Performance Index

Project	Company	Reference Value
Pressure Range	Mpa	0.5/1/2/5/10
Accuracy		0.5%F·S
Sensitivity	nm/FS	0.1%F·S
Temperature Range	℃	-20 to +80
Wavelength Range	nm	1527 to 1568
Pressure sensing plate size	mm	130
Shell material		316L
Tail fiber size	mm	3
Fiber Length	m	1.5
Interface Type		FC/APC
Protection Level		IP68