The most familiar civil engineering structure is reinforced concrete (RC) structure. Performance of structure undergoes changes during their service life with time. Thus, it is of great concern to monitor the health of RC structure. Structural health monitoring (SHM) is the art of detecting the changes in structure that influences its performance. Various techniques to monitor the health of structure are broadly studied worldwide. PZT based smart aggregate can play an effective role as an advanced tool in the development of structural health monitoring. This research work contributes for proposing a more generous Non-Destructive Evaluation (NDE) technique for structural health monitoring by using smart materials. If performance of a structure deviates from the design parameters with time, appropriate and effective maintenance is required. Considering the relevant need of RC structures, a more sensitive and cost-effective approach by using Electro-Mechanical Impedance (EMI) technique has been proposed for implementation in real-life situations. In general, surface bonded PZT transducer is used for SHM. Since PZT transducers are of very small dimension and brittle in nature, for consistent characteristics, they should be protected from severe environmental condition and other external interruptions. For this reason, PZT transducer is embedded in structure at the time of construction and manufacturing of the embedded transducer is simple. The proposed EMI technique assesses the health of RC structures more rationally by embedding PZT transducer in the structure, whose health is to be monitored over the user specified preset frequency range. The conductance and susceptance signatures are acquired by using LCR meter. At any future point of time, when it is desired to assess the health of structure, the conductance and susceptance signatures are acquired and further utilized for damage detection and quantification. The Root Mean Square Deviation (RMSD) is used to specify damage severity.

The transient dynamic elastoplastic bending analysis of plates is investigated. Higher-order shear deformation theory is employed for the purpose, so as to have more realistic transverse shear representation. The formulation requires C 0 continuity for nodal variables. Isoparametric parabolic finite element discretization is adopted. The yield criteria incorporated are von Mises and Tresca along with associated flow rules. The isotropic hardening is also included. Equations of motion are satisfied at discrete time intervals using direct integration method and central difference scheme. A special mass lumping scheme is adopted. As critical time step is very important in explicit integration scheme, precaution has been taken so as to have the time step smaller than the critical one. Numerical examples are solved and compared with solutions from literature. The formulation is shown to be superior in comparison to previous formulations, being more generic in all respects.

Damped transient dynamic elasto-plastic analysis of plate is investigated. A finite element model based on a C 0 higher order shear deformation theory has been developed. Nine noded Lagrangian elements with five degrees of freedom per node are used. Selective Gauss integration is used to evaluate energy terms so as to avoid shear locking and spurious mechanisms. Von Mises and Tresca yield criteria are incorporated along with associated flow rules. Explicit central difference time stepping scheme is employed to integrate temporal equations. The mass matrix is diagonalized by using the efficient proportional mass lumping scheme. A program is developed for damped transient dynamic finite element analysis of elasto-plastic plate.Several numerical examples are studied to unfold different facets of damping of elasto-plastic plates.

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