WINNER - PAVING DIVIDED HIGHWAYS
MDOT I-96 & I-675 Reconstruction
Location: Cities of Southfield, Farmington Hills, Novi, Wixom, And New Hudson
Concrete Contractor: Ajax Paving Industries, Inc.
Design Engineer: HNTB
QC Consultant: CT Consultants - A Verdantas Company
Project Owner: Michigan Department of Transportation
The $545 million I-96 Flex Route and I-696 Restore the Reuther projects span 21 miles of freeway reconstruction, including ramp reconstructions and new concrete barrier walls. Both projects were initiated by MDOT, with I-96 starting in late 2022 and I-696 following in 2023. Ajax Paving served as the concrete paver on both projects, which required careful planning and coordination to manage the overlapping timelines.
I-96 Flex Route Project - This project involved approximately 12 miles of reconstructed concrete pavement, a ramp metering system, and an Active Traffic Management System (Flex Lane) to reduce congestion. The flex lane uses the median shoulders for additional lanes during peak periods, improving traffic flow and safety. Key features include the rehabilitation of 12 bridges and installation of box culverts.
I-696 Reconstruction Project - I-696 included 9 miles of concrete pavement, cement-treated permeable base (CTPB), high-performance special concrete pavement, and the replacement of multiple concrete structures. This section of freeway, originally built in the 1960s, underwent significant repairs to extend its service life. MDOT implemented a high-performance special pavement section using dense aggregates for better durability and friction.
Construction
Over three years, Ajax established five portable concrete batch plants along the I-96/I-696 corridor, producing nearly 800,000 cubic yards of CTPB and high-performance concrete. Two plants were relocated between paving seasons to ensure sufficient material supply. The production involved 25 mix designs using various coarse and fine aggregates. In August 2024, the peak month, over 105,000 cubic yards were produced and placed. To maintain stockpiles and meet testing demands, approximately 30,000 tons of aggregate were delivered weekly, requiring meticulous planning.
The 21-mile project included highways ranging from 2 to 5 lanes wide, with limited ramp and freeway closures and strict timelines enforced by liquidated damages. Ajax handled trimming the 4G open-graded base, manufacturing and placing CTPB, and fine grading with GOMACO 9500 trimmers guided by Trimble grade control. On-site portable plants produced CTPB, relocated between 2023 and 2024 to optimize haul routes and avoid traffic. Two paving crews used asphalt pavers and rollers to place and compact the base material, with daily density and strength testing.
Ajax placed over 1.7 million square yards of high-performance concrete pavement, primarily 11-12 inches thick. Each year, unprecedented amounts of equipment were mobilized, including two mainline paving crews and a handwork crew for smaller pours. Equipment included 14 slip-form pavers (e.g., GOMACO 2800, 2600, 2400, GP3, GP4, & Commander III) with widths ranging from 12 to 26 feet, some equipped with dowel bar inserters (DBI) for mainline paving. Cure and texture machines were set up to accompany each paver’s width. Trimble stringless technology ensured precise alignment and elevation. Sawing and sealing crews used Core Cut saws and sealed over one million feet of joints with hot-poured rubber asphalt per MDOT specifications.
Quality control involved multiple ACI/MCA Level I-certified technicians with full equipment sets for concrete testing. Ride quality was monitored daily using Ames profilers, analyzed to meet Class 1, 2, and 5 specifications, with diamond grinding applied as needed for corrections.
Challenges and Solutions
The complex staging of paving activities, including closures and a complex traffic management plan (MOT), added extensive challenges. Ajax coordinated closely with MDOT to ensure that ramp and freeway closures met contractual deadlines and minimized disruption. Special attention was given to critical areas, including ramps and the I-696 section from I-275 to Lahser Road, where paving required precise handling due to traffic flow restrictions.
Quality Control and Technology
Quality control included the use of Ames profilers for ride quality checks, with daily testing to meet MDOT’s stringent specifications. Ajax developed maturity curves for the 24 mix designs and used maturity meters to monitor concrete temperature and strength in real time, allowing crews to make adjustments on-site and expedite construction.
Economic Impact
As part of the Rebuilding Michigan bond program, the project was vital for enhancing safety and reducing travel time on key corridors linking Detroit and Lansing. This 21-mile stretch, carrying over 200,000 vehicles per day, is a major route for commuter, commercial, and tourism traffic. The project is expected to support 6,700 jobs in Michigan.