Issue 63

L. A. Aboul-Nour et alii, Frattura ed Integrità Strutturale, 63 (2023) 134-152; DOI: 10.3221/IGF-ESIS.63.13

Figure 13: Validation load-deflection curve (a) effect of %core variation, (b) effect of a/d variation, (c) effect of RFT variation, (d) effect of connection method variation. Comparison between experimental and numerical results. Tab. 9 explains the comparison between numerical and experimental results attained for all studied slabs and reveals that the analytical method summarized here can be used to simulate LHCS behavior in an acceptable way when there is no material difference. The numerical results were accepted with the experimental results with a difference of less than 10 %. The failure load for the FEM is the last applied load before the starting divergence of the program due to the several cracks. The deflection at ultimate load is the vertical displacement in Y-direction (UY) at the mid-span of the slap for the FEM. Crushing or cracking in concrete elements is illustrated in the ANSYS program by displaying circles at the location. Fig. 14 shows the comparison of numerical and experimental cracking patterns for all the layered hollow-core slabs. The FEM also predicted similar failure modes.

Slab no.

LHCS 1

LHCS 2 LHCS 3 LHCS 4 LHCS 5 LHCS 6 LHCS 7 LHCS 8 LHCS 9

Exp. FEM

8.86 8.17

6.016 5.884 1.023

8.943

7.787 7.542 1.032

10.24 9.332 1.097

35.24

15.049 13.683

39.23

12.642

9.6

36.739

38.772

13.11 0.964

Pcr (kN)

Exp./FEM

1.084

0.932

0.959

1.100

1.011

Exp. FEM Exp. FEM

34.013 30.929 1.100 0.425 0.470

26.051 27.834 0.936 0.219 0.243

37.863 34.547 1.096 0.710 0.652

23.877 24.070 0.992 0.342 0.316

36.754 35.728 1.029 0.742 0.675

61.667 62.473 0.987 0.179 0.163

36.485 33.130 1.101 0.340 0.378

63.375 67.153 0.944 0.242 0.220

36.087 32.900 1.097 0.571 0.635

Pu (kN)

Exp./FEM

Δ cr (mm)

Exp./FEM

0.904 4.551 4.355 1.045 0.260 0.264

0.903 2.643 2.937 0.900 0.231 0.211

1.089 6.220 5.670 1.097 0.236 0.278 8.760 8.696

1.082 3.292 3.063 1.075 0.326 0.313 9.626 9.687

1.099 7.169 6.593 1.087 0.279 0.261 9.662 9.762

1.098 1.206 1.339 0.901 0.571 0.588 6.737 8.212

0.900 2.123 1.937 1.096 0.412 0.413 6.245 5.126

1.099 1.673 1.818 0.920 0.619 0.577 6.912 8.260

0.900 9.058 8.808 1.028 0.350 0.398

Exp. FEM

Δ u (mm)

Exp./FEM

Exp. FEM Exp. FEM

Pcr/Pu

10.707

12.069 12.105

15.863 13.881

Δ u/ Δ cr

9.265

Table 9: Experimental and numerical results for all specimens.

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