详情

原文传递 BRIDGE 9 ON SMITHS BRIDGE ROAD: WILMINGTON, DELAWARE.

题名：	BRIDGE 9 ON SMITHS BRIDGE ROAD: WILMINGTON, DELAWARE.
作者：	Oldham-SG; Weber-C
关键词：	Aesthetics-; Alignment-; Bridge-design; Bridge-substructures; Bridge-superstructures; Context-sensitive-design; Covered-bridges; Environmental-impacts; Floods-; Historic-bridges; Historic-preservation; Multimodal-transportation; Reconstruction-; Rehabilitation-Maintenance; Sight-distance; Traffic-calming; Traffic-safety; Vandalism-; Wilmington-Delaware
摘要：	Bridge 9 (Smiths Bridge) is a one-lane wide, three-span steel beam bridge with timber deck and railing with a superstructure dating from 1962 when it was rebuilt following a fire. The original superstructure was a single-span timber covered bridge constructed in 1839. The substructure consists of stone abutments dating back to the original 1839 bridge and stone faced concrete piers that were constructed in the 1950s when steel beams were added for support. The substructure is considered to be a contributing element to the historic district in which the bridge lies. The latest condition evaluation reports that the bridge deck is in poor condition, with the superstructure and substructure in fair condition. Based on the condition of the bridge, the scope of work was determined to include replacement of the superstructure and rehabilitation of the substructure. The context-sensitive design features include the following: giving consideration to aesthetics, historic issues, environmental concerns, noise concerns, multimodalism, traffic calming, safety, vandalism, and flooding; developing a replacement for the superstructure that is not a literal recreation of the historic structure, but is based on design qualities found in as-built drawings from 1956; building a one-lane covered bridge by getting a design exception to AASHTO design guidelines, determining an appropriate speed limit (20 mph), and realigning on the north side to provide better sight distances; and improving sight line distances by realigning and raising the approach from the west side of the bridge and by lowering the bridge deck by 1 ft.
总页数：	Transportation Research E-Circular. 2004/07. pp45-49 (3 Phot.)
报告类型：	科技报告