HBM-IDOT-PTB155 Item66-Manholes and Culverts
Statewide Structural Engineering Services
Illinois Department of Transportation
Contact: Jayme Schiff, PE, SE
AECOM USA, Inc.
Parsons Brinckerhoff, Inc.
Key Team Members
Mahmoud A. Issa, Rating Engineer Lisa Buntin, Rating Engineer John Saraceno, Team Leader Mohsen A. Issa, QC/QA Reviewer
Illinois Department of Transportation (IDOT) is in the process of developing a new IDOT Culvert Manual. The new IDOT Culvert Manual will be based on the 2012 AASHTO LRFD Bridge Design Specifications and current Interims. The study for Design Guidelines and Standards for Culverts is to be included in the new IDOT Culvert Manual.
The overall objectives of the box culverts portion of the project is to develop a guideline design criteria for the design of horizontal wingwalls, headwalls and interior walls of multi-cell culverts for IDOT use. All loading conditions were determined according to AASHTO standards. A linear finite element analysis was performed on single and double cell box culvert models using SAP2000. Guidelines were developed for horizontal wingwalls, headwalls, and interior walls of multi-cell box culverts. A report is currently being prepared that documents the research and findings performed.
Precast Reinforced Concrete Manholes
Illinois Department of Transportation (IDOT) is planning to develop guidelines for the design of precast reinforced concrete manholes. Currently, there is very limited guidance in IDOT policy for geometrics and the number and spacing of knockouts that can be allowed in a manhole. Consideration were given to the fact that manholes are usually of precast construction and that openings in the manhole wall are often significantly larger than the diameter of the pipe.
IDOT was looking for recommendations based on finite element analysis. Design was performed according to the 2012 AASHTO LRFD Bridge Design Specifications, 6th Edition (and all subsequent interims) while utilizing SAP2000 and in-house EXCEL and MathCAD programs.
The main objective of the precast reinforced concrete manholes investigation was the development of Standard Base Sheets, tables and specifications permitting the selection of a precast reinforced concrete manhole structure under variable conditions. The manhole loading requirements was determined. Finite element models were developed on 48 and 72 inches inside diameter manholes. An Interim Report Is currently being prepared that documents the research findings performed on the 48 and 72 inches inside diameter manholes.