Popis: |
Occurrence of damage is inevitable in structural system during the service life and this gets compounded with age of the structure and unanticipated loadings and environments the structure is subjected to. So it becomes important as part of maintenance to assess the current strength and this is gaining importance as rehabilitation is necessary for the upkeep of the infra-structure and also more economical than demolition. The design of structures is generally based on their virgin state omitting most damage processes that might happen and consequent structural stiffness degradation. Because structural failure could be catastrophic not only in terms of the loss in economy and life, but also in terms of the subsequent social and psychological impacts, accurate condition assessment of civil engineering structures has become increasingly important and hence it is necessary to simplify the approach for the damage analysis to effect immediate action on rehabilitation. The present study involving FE analysis includes damage by assessing reduction in properties like Young's modulus, Moment of inertia and area of cross section which need number of analysis for different levels of damage. Keeping attention only on grid system used in bridges, a MATLAB (7.0) -code was developed for analysis using grid elements. Damage is incorporated within the program through interaction, which could be used when damage analysis is to be done. In this study, the central nodal damage and non central nodal damage of the grillage is studied and its effects on the structure are being highlighted, with different design parameters like Bending Moment, Torsion moment, Deflection. Another important parameter is the skew angle of the grid and the response of the system in terms of stiffness and design aspects for mild and moderate nodal damage is the focus of current. � 2013 CAFET-INNOVA TECHNICAL SOCIETY. |