Development and Implementation of the Connecticut DOT ABC Program

September 7, 2021 11:00 am

The 2021 In-Depth Web Training features the development and implementation of the Connecticut Department of Transportation’s ABC Program. This training is four hours in length and consists of six modules, each a 30-minute presentation followed by a 10-minute Q&A session, with a 15-minute break between Module 3 and Module 4.

Description: The Connecticut DOT has a long history of the use of ABC, starting in the late 1980s and progressing to the institutional use of ABC today. This training focuses on several key features of the Connecticut DOT program. Early ABC projects are presented; these early ABC projects were the building blocks of the current CTDOT ABC program. In recent years, the Department developed a concise ABC decision tool that focuses on road user impacts as well as overall project costs, which can often offset the additional costs of some ABC technologies. This matrix includes a basic method for calculating vehicle delay time when subjected to detours or lane closures. The training includes two actual project examples, one where the matrix led to an ABC decision and another where ABC was not the solution for the superstructure. The final module in this training provides an overview of all the types of ABC that are in use in Connecticut.

Organizers & Presenters:

Timothy J. Fields, P.E.
State Bridge Engineer
Transportation Principal Engineer
Major Structures
Connecticut Department of Transportation
Office: 860-594-3217
Email: TimothyFields@ct.gov

Tim, employed by the Connecticut Department of Transportation (CTDOT) for over 36 years, has been the Principal Engineer for their Major Structures unit within the Division of Bridges since 2013. He is the Chair of CTDOT’s Bridge Standard Practices Committee, which manages and updates CTDOT’s Bridge Design Manual. Since 2011 Tim has served as CTDOT’s State Bridge Engineer and voting member representative on the AASHTO Committee on Bridges and Structures. He graduated with a BSCE degree from the University of Connecticut in 1984, joining CTDOT in 1985 and advancing through multiple positions in bridge engineering. He is a licensed professional engineer.

 

Michael P. Culmo, P.E.
Chief Bridge Engineer
CHA Consulting, Inc.
Office: 860-290-4100
Email: MCulmo@chacompanies.com

Mike is a Bridge Engineer with over 37 years of experience in the design of steel, concrete, prestressed concrete and timber bridges. He previously was employed by CTDOT in the Bridge Design Office for 13 years, where he designed some of the earliest uses of ABC including the first precast full-depth bridge deck project in 1988. Mike has special expertise in the field of accelerated bridge construction technologies and constructability engineering. He is the principal author of numerous publications in the field of ABC, including the 2018 AASHTO LRFD Guide Specifications for Accelerated Bridge Construction.  He is a licensed professional engineer.

Q&A Sessions for Modules 1-6 - pdf

Module 1: Early ABC Projects at the Connecticut DOT

by Timothy J. Fields, P.E., State Bridge Engineer and Transportation Principal Engineer, Major Structures, Connecticut Department of Transportation; and Michael P. Culmo, P.E., Chief Bridge Engineer, CHA Consulting, Inc.

Description: Several early ABC projects served as the building blocks of the current Connecticut DOT ABC program. At the time, ABC was chosen for these projects out of necessity, since there were no other traditional methods that would provide acceptable traffic management for the construction. This module focuses on the successes of these early projects, and how they were used to gain support within the Department and with Connecticut political leaders.

Module 1 recording (to be posted soon!)

Early ABC Projects at the Connecticut DOT - pdf of presentation

  • Early precast decks
  • Atlantic Street Bridge studies

  1. Early use of full-depth precast concrete deck panels, built in 1990 with weekend-only closures – Route 8 Viaduct, Seymour, CT

Module 2: Development of the CTDOT ABC Decision Matrix

by Timothy J. Fields, P.E., State Bridge Engineer and Transportation Principal Engineer, Major Structures, Connecticut Department of Transportation

Description: As ABC gained popularity across the country, CTDOT was looking to develop an ABC decision matrix. The goal was to develop a systematic process where road user impacts were not the only basis for an ABC decision. The Department looked to capture the potential savings in construction management costs through the use of ABC, which could be used as a major factor in the overall decision to use ABC. This module covers the development and components of the Connecticut DOT ABC decision process.

Module 2 recording (to be posted soon!)

Development of the CTDOT ABC Decision Matrix - pdf of presentation
Link to CTDOT's ABC Decision Matrix

  • Decision factors
  • User impacts
  • Cost factors
  • Weight factors
  • Early trial use

2. Screenshot of a portion of the Connecticut DOT ABC Decision Matrix

Module 3: Simplified Method for Calculating Road User Delays in ABC Projects

by Michael P. Culmo, P.E., Chief Bridge Engineer, CHA Consulting, Inc.

Description: The Connecticut DOT ABC Decision Matrix includes road user impacts for ABC projects when compared to conventional construction projects. The ABC decision process is typically one of the first portions of a project’s development. Often, detailed traffic simulations are not available at that time. The Connecticut DOT developed a simple method for calculating delay times for detours and roadways with reduced traffic lanes. This training covers the development of this simplified method and how it can be used for typical ABC projects.

Module 3 recording (to be posted soon!)

Simplified Method for Calculating Road User Delays in ABC Projects - pdf of presentation

  • Detour delay time calculations
  • Lane reduction delay calculations

3. Sample Detour Plan used for the Connecticut DOT ABC Decision Matrix

Module 4: Detailed Project Example 1 – ABC Decision Process, with Positive ABC Decision

by Michael P. Culmo, P.E., Chief Bridge Engineer, CHA Consulting, Inc.

Description: This module shows an example where ABC was studied, and found to be the selected option. The module explores the step-by-step process for completing an ABC decision process for a typical Connecticut bridge. It covers the type of construction that was considered, the constraints at the site, potential detours, and completion of the ABC matrix. This example results in an affirmative decision on the use of ABC.

Module 4 recording (to be posted soon!)

Detailed Project Example 1 – ABC Decision Process, with Positive ABC Decision - pdf of presentation

4. CTDOT ABC Project: I-395 over Route 85 – deck replacement with full-depth precast deck panels

Module 5: Detailed Project Example 2 – ABC Decision Process, with Negative ABC Decision

by Michael P. Culmo, P.E., Chief Bridge Engineer, CHA Consulting, Inc.

Description: This module shows an example where ABC was studied, but found to not be the selected option. The module explores the step-by-step process for completing an ABC decision process for a typical Connecticut bridge. It covers the type of construction that was considered, the constraints at the site, potential detours, and completion of the ABC matrix. The project chosen was a 3-lane interstate bridge replacement. The options investigated were (1) weekend closure with ABC superstructure (modular decked beams) and (2) staged construction. The staging required a long-term closure of one of the three lanes for each stage. The result of the decision process was that an ABC superstructure was not recommended, primarily due to the relatively low ADT (average daily traffic) on the bridge, making staged construction feasible. Several innovative methods were used in the project to minimize the duration of the stages, such as building new GRS-IBS (geosynthetic reinforced soil integrated bridge system) abutments beneath the bridge prior to the start of staging.

Module 5 recording (to be posted soon!)

Detailed Project Example 2 – ABC Decision Process, with Negative ABC Decision - pdf of presentation

5. CTDOT Potential ABC Project: I-395 over Tracy Road, Killingly – staged construction

Module 6: Overview of ABC Projects in Connecticut

by Timothy J. Fields, P.E., State Bridge Engineer and Transportation Principal Engineer, Major Structures, Connecticut Department of Transportation

Description: This module covers the significant experience with ABC in Connecticut. The various types of ABC methodologies are presented with brief information on each project. Projects include full-depth precast concrete panel decks, lateral slide systems, SPMT systems, and precast substructures.

Module 6 recording (to be posted soon!)

Overview of ABC Projects in Connecticut - pdf of presentation

6. First SPMT bridge system installation – I-84, Southington, CT