PSI - Issue 28

N.A. Kosheleva et al. / Procedia Structural Integrity 28 (2020) 1883–1891 Author name / Structural Integrity Procedia 00 (2019) 000–000

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ASTRO A322 interrogator (6) was used for data acquisition from FBGs during the entire formation process. The data obtained from FOSs during 720 hours with a sampling rate of 1 time per second were recorded into the database on a separate personal computer (7) as well as data from other sensors. The ambient temperature during the experiment varied in the range from 25 to 27˚С, and the humidity from 48 to 55%.

Fig. 1. Experimental stand.

To investigate the effect of sample geometry on the shrinkage, two types of samples were created. The first type is a cylinder with a diameter of 150 mm and a height of 400 mm (see Fig. 2 a). The molds for this sample were made of polypropylene. The second type of samples has prismatic shape with dimensions of 150  150  400 mm, and molds made of moisture-resistant plywood (see Fig. 2 b). Formation and hardening of all types of samples is carried out in the molds with a free upper surface.

a

b

Fig. 2. The scheme of samples with embedded fiber-optic sensors: sample 1 – cylinder (a); sample 2 – prism (b).