Composite bridge design optimisation using HFMI-treatment: Design and optimisation of composite bridges using high frequency mechanical impact (HFMI) treatment
| dc.contributor.author | Englund , Cecilia | |
| dc.contributor.author | Dagduk, Saffa | |
| dc.contributor.department | Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE) | sv |
| dc.contributor.department | Chalmers tekniska högskola / Institutionen för arkitektur och samhällsbyggnadsteknik (ACE) | en |
| dc.contributor.examiner | Al-Emrani, Mohammad | |
| dc.date.accessioned | 2024-07-02T10:55:06Z | |
| dc.date.available | 2024-07-02T10:55:06Z | |
| dc.date.issued | ||
| dc.date.submitted | ||
| dc.description.abstract | Bridges are structures that are usually subjected to repetitive loading which can cause fatigue damage. Welds are specifically sensitive when considering fatigue problems. Thus, a post-weld treatment called High Frequency Mechanical Impact treatment (HFMI-treatment) is one solution that has the potential to increase fatigue resistance. It can lead to reduced stress concentrations by improving the geometry and introducing counteracting stresses by the weld. Further, it can be useful to use high strength steel to increase the improvement even more. The effect of using HFMI-treatment on new bridge design is still not thoroughly studied. Therefore, HFMI-treatment is investigated by optimising a steel bridge design using higher strength steel and also reducing material usage. A structural design of a road bridge is performed considering the effect of HFMI-treatment of the different welded joints. Additionally, the effect of implementing HFMI-treatment on site when the bridge already has been erected is studied and compared to when treatment is implemented in a workshop. The study indicates that there is a significant decrease in utilisation ratios for fatigue limit states when HFMI-treatment is implemented. The effect of HFMI-treatment together with the use of higher steel grades resulted in enhanced fatigue performance and also remarkable material savings. The most economical option appears to be to use steel strength S460. On the other hand, S690 can help obtain a slender beam for nearly the same cost if the beam height is limited. However, high stress ranges can limit the improvement of HFMI which restricts the possibility of enhancing fatigue strength. The thesis concludes that implementing HFMI-treatment and increasing steel strength, in new bridge designs, can be significantly beneficial. The cost of performing the treatment is insignificant, and there is good potential for material and cost savings. Furthermore, the best outcomes are obtained when the treatment is implemented after erection. | |
| dc.identifier.coursecode | ACEX30 | |
| dc.identifier.uri | http://hdl.handle.net/20.500.12380/308199 | |
| dc.language.iso | eng | |
| dc.setspec.uppsok | Technology | |
| dc.subject | Bridges, Fatigue, Welds, Post-weld treatment, High frequency mechanical impact treatment (HFMI-treatment), High strength steels, Optimisation. | |
| dc.title | Composite bridge design optimisation using HFMI-treatment: Design and optimisation of composite bridges using high frequency mechanical impact (HFMI) treatment | |
| dc.type.degree | Examensarbete för masterexamen | sv |
| dc.type.degree | Master's Thesis | en |
| dc.type.uppsok | H | |
| local.programme | Structural engineering and building technology (MPSEB), MSc |