Table 3 Parameter calculation results.

From: Roadway rock burst prediction based on catastrophe theory

Stress of primary rock

/\({\text{MPa}}\)

a0

a1

a2

a3

a4

u

v

Δ

Catastrophe discrimination

1.25

1.000

1.000

1.000

1.000

1.000000

0.156

0.156

\(> 0\)

Stabilization

2.50

1.000

1.000

1.000

1.000

1.000000

0.156

0.156

\(> 0\)

Stabilization

3.75

1.000

1.000

1.000

1.000

1.000000

0.156

0.156

\(> 0\)

Stabilization

5.00

1.000

1.000

1.000

1.000

1.000000

0.156

0.156

\(> 0\)

Stabilization

6.25

1.000

1.000

1.000

1.000

1.000000

0.156

0.156

\(> 0\)

Stabilization

7.50

2.510

−0.014

0.045

−0.013

0.000853

−9.331

−18.174

\(> 0\)

Stabilization

8.75

2.339

0.230

−0.064

0.006

−0.000264

16.622

119.524

\(> 0\)

Stabilization

10.00

2.384

0.169

−0.039

0.002

−0.000066

70.417

757.109

\(> 0\)

Stabilization

11.25

2.507

0.017

0.017

−0.006

0.000304

−22.440

−87.427

\(> 0\)

Stabilization

12.50

2.544

−0.026

0.032

−0.008

0.000384

−18.782

−74.623

\(> 0\)

Stabilization

13.75

2.833

−0.344

0.132

−0.020

0.000839

−11.991

−42.417

\(> 0\)

Stabilization

15.00

2.365

0.143

−0.011

−0.004

0.000286

−29.133

−38.695

\(< 0\)

Catastrophic Change