The INDUSE project is motivated by the need of safeguarding the integrity of industrial equipment steel structures (liquid storage tanks, pressure vessels and piping systems), under earthquake loading.
In order to characterize the dynamic behavior of piping systems, Univeristy of Trento performed some pseudo-dynamic tests with dynamic sub-structuring on a typical industrial piping network, Figure 1. This type of test is a novel hybrid method for the dynamic testing of structures or systems.
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| Figure 1-left: Draft of the piping system tested | Figure 1-right: Photo of the piping system realized at University of Trento |
GaMoCap, the multi-camera vision system and a color-coded pattern attached to the structure, Figure 2, was used to evaluate the map of displacements of the pipe structure at elbow during a simulation of a earthquake.
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| Figure 2: Stereo camera system and color-coded marker attached on the elbow of the pipe. |
With respect to commercial systems already available on the market the GaMoCap has a significant advantage because it can recover a high density (50 markers in 100 cm^2) measurement of displacements and deformation of the structure in analysis maintaining high accuracy with respect to dense vision reconstruction methods that can outperform wrt resolution but can achieve a lower level of accuracy making them not suitable for measurement systems.
Below is a video of the 3D points reconstructed during a simulation of a earthquake with color-coded displacements.
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In Figure 3 are reported the key-frames of the video. It is possible to see how the pipe during the trial bend in the middle of the elbow.
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| Figure 3: Key frames of point reconstruction with colour-coded displacement respect time 0. |
Maximum and minimum displacements are compatible with the one obtained from the analysis of the numerical model of the structure.
The measurement campaign were conducted in the framework of INDUSE projects headed as P.I. of Local Unity of INDUSE at Univeristy of Trento by Prof. Bursi Oreste, with the help to Ph.D students Abbiati Giuseppe andMd. Shahin Reza.