In bridge health monitoring, tiltmeters have been used for measuring rotation and curvature; however, their application in dynamic parameter identification has been lacking. This study installed fiber Bragg grating (FBG) tiltmeters on the bearings of a bridge and monitored the dynamic rotational angle. The dynamic features, including natural frequencies and mode shapes, have been identified suc...

Abstract We report the tilt sensitivity reached by ARCHIMEDES tiltmeter in 2–20 Hz frequency region, where seismic noise is expected to give an important limitation next future Gravitational Waves detection, particularly through Newtonian noise. The level $$\tilde{\theta }(f)$$ θ ~...

General methods of displacement measurement are to use LVDT, tiltmeter, or laser deflection meter. But these methods can’t be applied effectively if bridge height is so high that the installation of sensor is difficult. So the great part of in these cases, the reliability and accuracy of measured results are uncertain usually. To overcome this problem, in this paper, the two techniques for calc...

[1] An Earth tide signal at the lunar tidal period of 12 hours 25 min has been detected in the Sagnac frequency record of the C-II ring laser 30 m underground at Christchurch, New Zealand. Its amplitude, one part per million of the Earth rotation signal, is much greater than the value of 40 parts per billion expected. Tiltmeter records show that a substantial part of this amplification is geoph...