Laserfiche WebLink
SECTIONONE project Description <br /> 1.1 PROJECT DESCRIPTION <br /> This report focuses on the geotechnical adequacy of the proposed structure to carry Brush <br /> College Road over multiple Norfolk Southern railroad lines in Decatur, Illinois. The site is <br /> located in Sections 7 and 8, Township 16 North, Range 3 East of Macon County. See Figure 1 <br /> for the site location drawing. <br /> The existing site consists of a dual-span underpass structure carrying the Norfolk Southern (NS) <br /> lines over Brush College Road and a single Illinois Central (IC) railroad line. The structure <br /> consists of 20" to 24" wide-flange and I-shape steel beams supported on concrete closed <br /> abutments and a pier that are founded on spread footings. An approximate 55-foot-long gap <br /> exists in the decking between two main sets of Norfolk Southern lines. The west span of the <br /> istructure is approximately 22 feet long and carries the NS lines over the IC line, while the east <br /> span is approximately 30 feet long and carries the NS lines over Brush College Road, which is <br /> reduced from two lanes with a middle turn lane down to two 11-foot-wide lanes and 3-foot-wide <br /> sidewalk through the underpass. <br /> ' The proposed construction will consist of backfilling the east span of the existing underpass <br /> structure while maintaining the west span open for the IC track. The existing structure will be <br /> left in place to carry the NS railroad lines over the IC line and the backfill. The proposed six- <br /> span overpass structure will carry Brush College Road over the NS railroad lines with four 12- <br /> foot-wide lanes and a single 12-foot shared-use path. Including parapets, medians, and <br /> shoulders, the total deck width is approximately 72 feet. The spans will consist of steel plate <br /> girder beams placed on pile-bent piers and stub abutments for a total structure length of <br /> approximately 931 feet. Mechanically stabilized earth (MSE) walls will support the approach <br /> embankments, while an MSE and/or concrete cantilever wall will support the underpass backfill <br /> adjacent to the IC railroad line. The proposed alignment for the new structure will be shifted east <br /> of the existing underpass to allow traffic staging on Brush College Road during construction. <br /> Due to the required length, an integral structure was not considered. <br /> U ELM <br /> MS <br /> 1-1 <br /> r <br />