The concept of Pseudo load is introduced and explained in this thesis. A methodology based on Pseudo load has been developed that can reliably simulate the damage response of structures with realistic noise and uncertainties observed in the field. The method is applied and tested on numerical examples with field captured vibration data having realistic noise and uncertainties as well as on random data. It is shown that the Pseudo load method is effective in preserving the influences of noise and uncertainties in the simulated damage vibration response of the example structures. The limitations in the developed Pseudo load methodology are identified and resolved. The methodology is implemented on the Confederation Bridge to obtain simulated field damage responses of the bridge for further research on the development of vibration based structural health monitoring algorithms and tools.