Structural health monitoring (SHM) is a process based on damage identification algorithms to provide an economical and possibly more reliable solution to infrastructure condition assessment. The main principle of SHM is based on using vibration data that are acquired by dynamic tests. Ambient loads are one of the useful and applicable vibration forces that are widely used in the civil infrastructure. The main objective of this study is to compare some numerical methods including state space method (SSM), linear Newmark method (LNM), and central difference method (CDM) for the simulation of acceleration time history caused by applying the ambient vibration. In order to demonstrate the results of numerical simulation, a numerical model of the reinforced concrete beam is constructed based of finite element modelling. Caughey damping model is applied rather than Rayleigh model due to considering two more modes in the dynamic behaviour of structure. To excite the structure, different Gaussian white noises are subjected to all the transitional degree of freedoms that virtually equipped with sensors. Numerical results show that both SSM and LNM one can reliably simulate the acceleration responses; however, the state space method obtains more accurate responses. In contrast, the CDM cannot provide meaningful and trustworthy results.

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