Table 6 Thermal critical buckling load \({\mathcal{T}}_{cr}\) of square perfect and imperfect FG plates exposed to linear thermal loading for various values of plate thickness ratios \(a/h\), porosity parameter \(\tau\) and volume fraction indices \(\mathfrak{r}\).

From: The porosity effect on the buckling analysis of functionally graded plates under thermal environment using a Quasi-3D theory

\(\mathfrak{r}\)

\(a/h\)

Theory

\(\mathcal{q}\)

Perfect

Imperfect I (even)

Imperfect II (uneven)

Imperfect III (logarithmic-uneven)

\(\tau =0\)

\(\tau =0.1\)

\(\tau =0.2\)

\(\tau =0.1\)

\(\tau =0.1\)

\(\tau =0.1\)

\(\tau =0.2\)

0

5

HPT18

\(=0\)

11159.22

14046.50

18946.93

12555.54

14274.56

12518.32

14096.82

Present

\(=0\)

11156.80

14043.45

18942.82

12553.96

14274.27

12516.72

14096.39

Present

\(\ne 0\)

11744.80

14783.46

19940.81

13211.59

15017.18

13172.50

14830.50

10

HPT18

\(=0\)

3227.50

4064.41

5484.84

3643.99

4158.39

3632.87

4105.13

Present

\(=0\)

3227.36

4064.23

5484.60

3643.93

4158.46

3632.81

4105.18

Present

\(\ne 0\)

3278.75

4128.90

5571.82

3701.77

4224.26

3690.48

4170.16

20

HPT18

\(=0\)

833.07

1051.01

1420.91

942.47

1077.71

939.54

1063.70

Present

\(=0\)

833.07

1051.00

1420.89

942.46

1077.72

939.54

1063.71

Present

\(\ne 0\)

836.59

1055.44

1426.87

946.44

1082.25

943.50

1068.18

1

5

HPT18

\(=0\)

5001.89

5474.11

6019.52

5341.39

5711.79

5332.82

5675.72

Present

\(=0\)

5000.95

5473.12

6018.49

5341.07

5712.37

5332.48

5676.19

Present

\(\ne 0\)

5365.35

5899.26

6530.35

5735.74

6141.16

5726.37

6101.61

10

HPT18

\(=0\)

1413.02

1539.29

1681.31

1514.01

1624.97

1511.45

1614.13

Present

\(=0\)

1412.96

1539.23

1681.26

1514.01

1625.05

1511.45

1614.20

Present

\(\ne 0\)

1473.78

1615.64

1780.54

1582.32

1702.19

1579.57

1690.45

20

HPT18

\(=0\)

358.71

390.86

426.74

385.24

414.45

384.57

411.59

Present

\(=0\)

358.71

390.85

426.73

385.24

414.46

384.57

411.60

Present

\(\ne 0\)

370.96

407.02

448.74

399.31

430.69

398.59

427.61

5

5

HPT18

\(=0\)

3902.54

3949.18

3624.56

4037.93

4122.04

4035.12

4117.49

Present

\(=0\)

3908.08

3956.99

3634.52

4048.61

4141.72

4045.63

4136.07

Present

\(\ne 0\)

4190.70

4284.42

4014.10

4347.69

4454.78

4344.32

4448.01

10

HPT18

\(=0\)

1160.21

1170.98

1057.33

1218.81

1269.84

1217.45

1265.62

Present

\(=0\)

1160.75

1171.71

1058.23

1219.85

1271.79

1218.47

1267.46

Present

\(\ne 0\)

1219.95

1250.28

1162.30

1287.90

1350.29

1286.29

1344.91

20

HPT18

\(=0\)

298.67

301.50

270.71

315.74

331.60

315.33

330.22

Present

\(=0\)

298.70

301.55

270.77

315.81

331.74

315.40

330.357

Present

\(\ne 0\)

311.98

320.42

297.24

331.66

350.80

331.18

349.07