PSI - Issue 63

Stanisław Majer et al. / Procedia Structural Integrity 63 (2024) 51–57

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was located at half the height of the sample. The following procedure was applied in the Elastic modulus test (Fig. 3, Fig. 4):  the sample was loaded up to compressive stress of  b = 0.05 MPa and the resulting strain  b0 was measured  the test load was increased up to  a =1/3 f c , maintained for 60 s at that level, and after the next 30 s  a0 was measured  the sample was unloaded to stress level  b , which was maintained for 60 s and after the value of  b1 was measured (Fig 3),  this procedure was repeated at least 2 times,  when all the required values had been determined, load was increased up to failure of the sample (Fig 4). The elastic modulus of CBM materials was investigated using the stress-strain relationship of the mixture from the test. The elastic modulus (E) is calculated by equation below: ܧ ൌ ఙ ఢ (1)

Fig. 3. Load increase over time during the E-modulus test.

Fig. 4. Stress-strain plot of one of the tested mixes.