PSI - Issue 33

Irina A. Bannikova et al. / Procedia Structural Integrity 33 (2021) 357–364 Author name / Structural Integrity Procedia 00 (2019) 000 – 000

361 5

A

B

Fig. 5. PMT signals (yellow) obtained as a result of uniaxial quasi-static loading of quartzite (specimen No. 1). А – single impulses – Stage 1 of damage is the spread of cracks from stress concentrators. B – multiple impulses – Stage 2 is the complete failure of the sample.

A

Vertical cracks

-6

-6

-7

1.24*10

s

1.49*10

s

9.94*10

s

Vertical cracks

-6

-6

-6

-6

2.86*10

s

3.11*10

s

1.86*10

s

4.23*10

s

-6

-6

-6

-6

6.34*10

s

4.68*10

s

4.72*10

s

5.97*10

s

-5

-5

-5

-5

1.29*10

s

3.60*10

s

1.14*10

s

1.59*10

s

Fig. 6. The glow of a quartzite cylinder (sample No.4) under quasi-static loading. The frames indicate the time relative to frame A.

3.2. Dynamic loading Sample No. 3 was destroyed as a result of dynamic loading by Split Hopkinson pressure bar with the strain rate was 1000 s -1 . A detailed description of the setup is given earlier in the work of the authors Davydova and Uvarov (2013). Air is pumped into the high-pressure chamber with the help of a pump. After opening the valve, compressed