PSI - Issue 70

P. Saravana Kumar et al. / Procedia Structural Integrity 70 (2025) 43–50

47

3.1.3 Dynamic Characteristics A beam when subjected to a dynamic loading can be idealized as a system with single degree of freedom. The components of the single degree freedom are 1. Mass of the beam, M 2. Spring with stiffness k due to the flexural stiffness of the beam 3. Dashpot with damping coefficient C The idealized single degree of freedom system is shown in below. During impact loading a large force acts on the system for a very short duration of time, the structure vibrates as a free vibrating system since the force is removed after a short period of time. Hence the beam can be considered as a free vibrating system for dynamic analysis.

Table 3. Energy- Deflection for ISMB 200 Energy(N mm)

Deflection (mm)

0

0

98.1

0.7 1.1 1.8 2.5

196.2 294.3 392.4 490.5

4.73

Table 4. Energy-Deflection for ISMB125 Energy(N mm)

Deflection (mm)

0

0

98.1

1.78

196.2 294.3 392.4 490.5

3.5 5.5 8.8

12.4

Table 5. Energy-Deflection for ISMB100 Energy(N mm)

Deflection (mm)

0

0

98.1

0.15

196.2 294.3 392.4 490.5

0.3

0.65

1.8 4.1

4. Results and discussion 4.1. Experimental Result

Steel beams of three different sections were tested under a gradually increasing load applied at the center of the span. Deflection readings were recorded at regular intervals, and the corresponding load-deflection values were calculated. Load vs. deflection graphs were plotted for each beam section. The experimental results closely matched the theoretical predictions, confirming the reliability of the analytical methods. The stiffness values obtained for