In 1994 and 1995, Associated Engineering was responsible for upgrading the fatigue endurance of the North Approach spans to the Skybridge on the SkyTrain Guideway System. When an initial structural analysis indicated that the other section of steel Guideway on the system would benefit from enhanced fatigue capacity, BC Transit, again, engaged Associated Engineering to complete the structural upgrade.
Associated Engineering designed the upgrade for the section of Guideway near Grandview Cut using the same, innovative, technique developed for the North Approach. The design involves the use of Spirol pins to increase the connectivity between the steel-box girder and the concrete deck, thereby improving the shear fatigue capacity.
The scope of work completed by Associated Engineering for the Grandview Cut structural upgrade includes:
- Completing additional analysis to establish the shear capacity and deficiencies of the existing structure
- Developing an upgrading philosophy
- Coordinating a limited testing program on specimens to ensure that the results of the original fatigue testing program carried out for the North Approach spans can be adapted to this application
- Designing fatigue shear capacity improvements
- Developing construction specifications and drawings for the upgrading work.