F.A.U. Route  7158, Mattis Avenue Over F.A.I. 74

The project involves the total replacement of the existing structure. The existing structure consists of a two-span 48″ web steel plate girder bridge supported by open stub abutments on concrete piles and multi-column reinforced concrete piers on spread footings. The existing structure is 249′-10 ¾” back-to-back abutments and 71′-7″ out-to-out deck with 40°-51’-29” left forward skew. The proposed two-span (141’-1” / 169’-7 ½”) continuous welded steel plate girder (70” web) structure on multi-column piers and stub abutments will be 320’-1 ¾” back to back abutments, 84’-0” out to out, with a 41°-19’-30” left forward skew. Stage construction will be required to maintain two lanes of traffic during stage I by utilizing a portion of the existing structure and then maintain one lane of traffic during Stage II on the Stage I part of the proposed structure. Adequacy of the existing and new structures during stage construction will be verified. In the event that the existing structure is determined to be inadequate for Stage I traffic, the structure will either be posted, or repair plans will be provided, depending on what is required. Due to spans exceeding 150 ft., the positive and negative moments shall be poured separately per IDOT Bridge Manual Sec. 3.2.8. Mandatory transverse construction joints will be specified along with a deck pouring sequence. Temporary Sheet Piling will be designated for construction of the proposed abutments and detailed according to the 2012 IDOT Bridge Manual. Temporary Soil retention will be designated for construction of the proposed pier. The soil nail wall will be constructed after completion of Stage II construction. This will limit the length and retained height of temporary sheet piling at the north abutment as well as eliminate the need to stage the construction of the soil nail wall.