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Indexed by:Journal Papers

Date of Publication:2015-07-04

Journal:INSTRUMENTATION SCIENCE & TECHNOLOGY

Included Journals:SCIE、EI

Volume:43

Issue:4

Page Number:429-445

ISSN No.:1073-9149

Key Words:deformation; digital image processing; bidirectional dynamic triaxial instrument; hydraulic servosystem; earthquake simulation

Abstract:This article reports the development of a novel bidirectional dynamic triaxial instrument. According to the seismic analysis of soil mechanics for major geotechnical engineering projects, there is an absence of instrumentation to simulate level and horizontal earthquake loads and hence a new design is reported here. The bidirectional dynamic triaxial instrument was built using a hydraulic servo system, which had excellent dynamic response and generated bidirectional excitation force/stress with designed amplitude ratios, phases, and waveforms. Advanced digital image measurement was used to characterize the dynamic deformation of soil in three dimensions. The application of the digital image processing is described in detail. The axial average length, radial average diameter, average cross-sectional area, and volume of soil were easily determined. This non contact measurement is an innovation showing that bidirectional excitation with varying amplitude and phase were satisfactory. The deformation of the soil was readily obtained. The bidirectional dynamic triaxial instrument provides advanced measurements of the characteristics of soil under strong earthquake or complex stress conditions.