Structural Health Monitoring (SHM) is an emerging field in civil engineering that offers the potential for continuous and periodic assessment of the safety and integrity of civil infrastructures. Based on previous structure condition knowledge, certain preventive measures can be adopted to prolong the service life of the structure and prevent catastrophic failure. Global Positioning System (GPS) is one of the major methods utilized in SHM. However, as the technical feasibility of using GPS for recording relative displacements has been proven, the challenge issue for users is to determine how...