| Author | Sirodom Somboon |
| Call Number | AIT Thesis no.ST-18-27 |
| Note | A thesis submitted in partial fulfillment of the requirements for the degree of Master of Engineering in Structural Engineering, School of Engineering and Technology |
| Publisher | Asian Institute of Technology |
| Abstract | This study presents a new method of the Structural Health Monitoring Technique (SHM) by the normalized modal strain approach (NMS). A physical model of a 3-continuous span reinforced concrete bridge was constructed in AIT laboratory. The model was scaled down from prototype bridge located in Thailand with scale factor 1/20, followed the similitude law to obtain the similar characteristics as the prototype. Two different types of strain gage including metal foil gage and semi-conductor gage were installed on transverse and longitudinal reinforcement along the span length to monitor the strain level during the vibration of the model. The dynamic excitation was applied to the specimen while strain responses of structure were simultaneously recorded. Free-decay of the strain signal was computed in frequency domain by Fast Fourier Transform (FFT) to establish the modal frequency and modal strain of undamaged and damaged stages. The comparison of the NMS was carried out to evaluate the damage location on the structure. The changes in frequency and NMS were observed at some locations, meanwhile, cracks were noticed at the same locations as the NMS indicated. Moreover, the capability for damage detection of metal foil gage and semi-conductor gage was compared. Several observations were discovered during the test. Lastly, it can summarize that the NMS is applicable for the damage identification on bridge structure. |
| Year | 2018 |
| Type | Thesis |
| School | School of Engineering and Technology (SET) |
| Department | Department of Civil and Infrastucture Engineering (DCIE) |
| Academic Program/FoS | Structural Engineering (STE) /Former Name = Structural Engineering and Construction (ST) |
| Chairperson(s) | Punchet Thammarak ; |
| Examination Committee(s) | Pennung Warnitchai;Thanakorn Pheeraphan ; |
| Scholarship Donor(s) | Royal Thai Government Fellowship ; |