Buy article PDF
The purchased file will be sent to you
via email after the payment is completed.
US$ 35
|
Structural Engineering and Mechanics Volume 39, Number 4, August25 2011 , pages 465-498 DOI: https://doi.org/10.12989/sem.2011.39.4.465 |
|
|
|
Bilinear elastodynamical models of cracked concrete beams |
||
Umesh Kumar Pandey and Gurmail S. Benipal
|
||
| Abstract | ||
| Concrete structures are generally cracked in flexural tension at working loads. Concrete beams with asymmetric section details and crack patterns exhibit different flexural rigidity depending upon the sense of the applied flexural moment. In this paper, three different models, having the same natural period, of such SDOF bilinear dynamical systems have been proposed. The Model-I and Model-II have constant damping coefficient, but the latter is characterized by two stiffness coefficients depending upon the sense of vibration amplitude. The Model-III, additionally, has two damping coefficients as well. In this paper, the dynamical response of Model-III to sinusoidal loading has been investigated and compared with that of Model-II studied earlier. It has been found that Model-III exhibits regular and irregular subharmonics, jump phenomena and strong sensitivity to initial conditions, forcing frequency, system period as well as the sense of peak sinusoidal force. The constant sustained load has been found to affect the natural period of the dynamical system. The predictions of Model-I have been compared with those of the approximate linear model adopted in present practice. The behaviour exhibited by different models of the SDOF cracked elastic concrete structures under working loads and the theoretical and practical implications of the approach followed have been critically evaluated. | ||
| Key Words | ||
| bilinear dynamics; bilinearity ratio; cracked concrete structures; jump phenomena; sensitivity to system parameters; stability portrait; sub-harmonic resonance | ||
| Address | ||
| Umesh Kumar Pandey: Department of Civil Engineering, National Institute of Technology, Hamirpur (H.P.)-177005, India Gurmail S. Benipal: Department of Civil Engineering, Indian Institute of Technology Delhi, Hauz Khas, New Delhi-110016, India | ||