SEI-IL February Dinner Meeting: Lightweight Modular Accelerated Bridge System for Managed Car Lanes

Presented by:                                                                                                     

Sam Mittal, PE, SE

Project Manager

Horner & Shifrin

There is a widening infrastructure investment gap in a large number of countries. To keep up with urbanization trends and population growth, investments in infrastructure need to increase by more than 60% globally. In United States, the Eisenhower era infrastructure is over 55 years old and past the 50-year bridge design life. Aging infrastructure requires high maintenance dollars. On the other hand, severe congestion on important urban interstate corridors is leading to prohibitive economic costs. Top 10 highway interchange bottlenecks in the country cause an average of several million truck hours of delay. An estimated $700 billions of infrastructure investments were required between 2016 and 2020 to fix the huge backlog of highway repair work and to keep pace with the infrastructure consumption. The actual investments have only been a trickle of what is needed.

The US Highway system moves 65% of freight and 85% of passenger traffic. Research has revealed that the Bridge infrastructure is grossly overdesigned due to high numbers of single occupancy vehicles. This presentation proposes use of managed car lanes to relieve pressure on existing infrastructure by giving policy planners a tool to effectively augment and manage existing Bridge infrastructure network. The presentation defines a notional car load and presents an Accelerated Bridge System. This system combines Metal Grid Deck systems with Simple for Dead and Continuous for Live Load approach to create a rapidly scalable installation system for Highway Bridges especially for managed car lanes. The higher initial cost of Metal Grid Decks is offset by quicker installation, lower cost of construction, and longer service life. The modular approach makes for easier construction, which is further enhanced by the light weight superstructure.

Sam Mittal serves as a Project Manager in the Chicago office of Horner & Shifrin. Sam has 15 years’ experience delivering projects throughout the country and internationally. During his career he has worked on complex steel, concrete segmental, tied-arch and other bridge types. Sam is a licensed Professional Engineer in five states, Structural Engineer in Illinois and has authored five research papers. Sam earned his bachelor’s from the National Institute of Technology, master’s from University of Cincinnati, and MBA in finance from University of Chicago.