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The effects of support in steel bridges can present significant challenges during the construction. The tendency of girders to twist or layovers during the construction can present a particularly challenging problem regarding detailing cross-frames that provide bracing to steel girders. Methods of detailing cross-frames have been investigated in the past to identify some of the issues related to the behavior of straight and skewed steel bridges. However, the absence of a complete and simplified design approach has led to disputes between stakeholders, costly repairs and delays in the construction.The main objective of this research is to develop a complete and simplified design approach considering construction, fabrication and detailing of skewed bridges. This objective is achieved by comparing different detailing methods, understanding the mechanism by which skew effects develop in steel bridges, recommending simplified methods of analysis to evaluate them, and developing a complete and simplified design procedure for skew bridges. The main conclusion of this research is that lack-of-fit effects for the Final Fit detailing method at the steel dead load stage are equal and opposite to the lack-of-fit effects for the Erected Fit detailing method at the total dead load stage. This conclusion has helped using 2D grid analyses for estimating these lack-of-fit effects for different detailing methods.

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An experimental investigation compared repair methods that could be used to repair timber piles in timber pile bridges. Five full-scale timber pile specimens with different levels of damages were prepared. The damage in each specimen was repaired with fiberglass-reinforced plastic wrap to encapsulate the damaged region, which was filled either with resin or grout or with resin and gravel. Ultimate load tests were carried out on the specimens to evaluate the effectiveness of the repair methods. Test results showed that grout was more effective than resin in repairing large cavity-type damage. Resin appeared to be more effective in repairing cracks and small cavities in timber piles. The failure load of the repaired pile specimens was at least five times greater than the design load capacity of the timber piles and indicated that the repair methods effectively restored the capacity of the damaged timber piles.

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