The DeSoto bridge is in an area classified as a marine environment and is anticipated to be classified as “extremely aggressive” for both the substructure and superstructure. The other bridges are located outside of a marine environment are anticipated to be classified as “moderately aggressive” for both the superstructure and substructure.

It is anticipated that the DeSoto bridge will utilize a superstructure consisting of approximately 150-foot to 170-foot spans that use FIB-72 or FIB-78 girders. The US 301 bridge over US 41 NB is anticipated to have a superstructure consisting of FIB 54 or FIB 63 girders for a 140-foot span. The US 41 bridge over US 301 is anticipated to have a superstructure consisting of FIB 63 or FIB 72 girders for 150-foot spans. The US 41 bridge over the CSX RR Short Line is anticipated to have a superstructure consisting of FIB 54 or FIB 63 girders for a 140-foot span. The majority of the elevated viaduct structure is anticipated to have varying spans from 100-foot to over 200-foot that utilize FIB 36 to FIB 96 girders. There is the potential for the elevated viaduct structure to utilize steel plate girders for spans longer than 200-foot and for areas where the roadway geometries require curved spans. Other superstructure alternatives for the elevated viaduct include post-tensioned segmental box girders and steel box girders.

These span lengths are considered reasonable for standard construction and delivery methods and routes, and the weight of these beams is not expected to require special coordination with FDOT's Permit Office for Over-Weight/Over-Dimension vehicles. The arrangement of the spans and the type of superstructure will be further evaluated during the design phase and documented in the Bridge Development Report (BDR).

It is anticipated that the DeSoto Bridge and the US 41 over US 301 Bridge will utilize multi-column piers and that the elevated viaduct structure will utilize single column piers. Both pier types may potentially have flared or tapered caps and/or columns to produce a visually appealing structure. Some of the elevated viaduct structure piers may have to utilize non-flared or non-tapered columns and/or caps to meet the minimum vertical clearance requirements. It is anticipated that the mechanically-stabilized earth (MSE) walls can have an aesthetic finish applied to enhance the visual appeal if desired.

Aesthetics will be further evaluated during the design phase and documented in the BDR.

It is anticipated for the DeSoto Bridge will have a substructure consisting of two multi-column piers that can be independently constructed during the two construction phases. All piers are

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