Literature for SHM can be divided according to their solution domains.

• Static Domain
• Modal Domain
• Frequency Domain
• Impedance domain

Static domain

In the presence of damage, stiffness matrix of a structure changes causing changed displacement of the structure due to static load. This change is one of the criteria used for the detection of damage. Jenkins et al [1997] have introduced a static deflection based damage detection method. Zhao and Shenton [2005] have presented a novel damage detection method based on best approximation of dead load stress redistribution due to damage. For self-equilibrating static load (usually generated by smart actuator) the effect of load on the static response becomes negligible far away from the actuator even in the presence of damage. Hence, the change of structural properties distant from the actuator cannot be sensed through static self-equilibrating load and the use of smart actuator for SHM in static domain is limited.