Replacing aging bridge infrastructure over a major interstate highway is one of the most demanding challenges in modern construction. When Michigan’s US-10 over I-75 needed new spans to replace bridges originally built in the 1950s, contractor C.A. Hull Co. had to work within tight overnight lane closures while maintaining safety and precision. The solution relied on tandem crane lifts using Terex crawler cranes to erect 16 steel I-beams per span in just two eight-hour windows. Understanding how such complex lift operations are planned and executed requires a solid grasp of fundamental Key Facts About Construction Project Life Cycle Phases and the specialized equipment choices that drive successful infrastructure delivery.
The Challenge of Replacing 1950s Bridges Over a Busy Interstate
The two bridge spans carrying US-10 over I-75 near Bay City, Michigan, were originally constructed in the 1950s, when traffic volumes were a fraction of modern levels. Nearly 57 years after their original construction, these structurally deficient, two-lane bridges required full replacement to safely handle the 31,800 vehicles per day (VPD) crossing over them. The situation was further complicated by the fact that more than 50,000 vehicles per day passed beneath the interchange on I-75 itself.
A $6.4 Million Infrastructure Investment
The Michigan bridge replacement project represented a $6.4 million investment in public safety and mobility. In less than seven months, C.A. Hull Co. of Walled Lake, Michigan, transformed the outdated spans into modern structures designed to serve decades more of service life. The new bridges feature concrete decks resting on prestressed concrete I-beams that replaced the structurally deficient original spans.
Traffic Constraints and the 8-Hour Overnight Window
The most significant constraint on the project was time. Interstate lane closures were permitted only between 10 p.m. and 6 a.m., giving crews exactly eight hours per night to complete all beam placement, false decking installation, and fascia platform work. For construction spanning the southbound I-75 lanes, eight beams had to be erected along with all associated decking and platforms within that single overnight window. The remaining eight beams spanning northbound I-75 were placed the following night. This left no room for delays, equipment failures, or procedural errors.
Rick Smith, Project Manager for C.A. Hull, noted that time was the single biggest challenge affecting the lifts. Every minute of the eight-hour window had to be used productively, from the moment lanes closed to the moment they reopened for morning traffic.
Selecting the Right Lifting Equipment for Bridge Construction
Choosing the right cranes for a bridge beam placement project is a critical decision that affects safety, schedule, and cost. For the US-10 bridge replacement, each of the 16 I-beams measured 104 feet in length and weighed approximately 43 tons. With 32 beams total across both directions, the lifting plan had to be both efficient and repeatable. The contractor evaluated multiple approaches before settling on the final equipment configuration. Understanding Different Types of Prefabricated Bridge Elements and Systems for Bridge Construction helps clarify why specific lifting solutions are chosen for different span configurations.
Evaluating Crane Options: Single vs Tandem Lifts
C.A. Hull considered two primary alternatives for placing the I-beams:
- Single large hydraulic crane positioned at one location to lift and place each beam. This option would have required multiple repositioning of the crane for load rating adjustments based on radius changes. It also would have needed I-75 lane closures before the crane could even be set up.
- Tandem lift using two smaller crawler cranes positioned on opposite sides of the bridge alignment. One crane would sit in the median separating northbound and southbound lanes, while the other would be placed adjacent to the abutment wall on the shoulder. This approach allowed both cranes to remain in position while handling all beam placements.
Project Engineer Elias Motz confirmed that the single crane option would not have allowed the crew to complete all lifts, false decking, and fascia platform installations within the allotted overnight timeframe. The tandem approach was clearly the superior choice for the schedule-driven nature of this project.
Why Terex Crawler Cranes Were the Right Fit
The contractor selected Terex HC 165 and HC 110 lattice boom crawler cranes for the tandem lift operation. These machines were chosen specifically for their combination of high lift capacity and compact size, which was essential given the congested workspace constraints of the jobsite.
Key selection factors included:
- Compact track width: The HC 110 measured only 18.6 feet wide, allowing it to fit within the narrow median of I-75. The HC 165 had a 20.7-foot track-to-track width and was positioned on the interstate shoulder near the abutment wall.
- Ease of transport: The HC 165 required eight truckloads for the 90-mile trip from C.A. Hull’s yard to the jobsite, while the HC 110 needed only five. A four-person crew could set up each crane in under five hours.
- Hydraulic counterweight system: Both cranes featured a hydraulic counterweight install and removal system that eliminated the need for an assist crane during assembly and disassembly. The HC 165 could lift its entire 108,400-pound upper counterweight stack into position in a single operation.
- Boom configuration: The HC 110 was equipped with 110 feet of main boom and a 4-part line, while the HC 165 carried 160 feet of main boom with a 4-part line.
Executing the Tandem Crane Lift Operation
With the equipment selected and positioned, the execution phase required precise coordination between crane operators, rigging crews, and traffic control personnel. The tandem lift method meant that both cranes had to work in perfect synchronization to lift, move, and place beams weighing 43 tons each without incident. The structural engineering principles behind such operations share similarities with those found in a Guide to Royal Gorge Bridge Structural Elements, where load distribution and precise placement are equally critical.
Coordinating Two Cranes in a Confined Workspace
The lifting plan positioned the HC 110 crane in the median of I-75, where it remained stationary during each lift. The HC 165 crane, with its larger capacity, was positioned on the shoulder and actually crawled during the lift to ensure each beam was properly aligned and placed on the pier supports.
This coordinated movement required careful pre-planning and communication between operators. Because the HC 110 stayed in one position while the HC 165 moved, the team had to account for changing load radii and ensure that both cranes maintained safe load capacities throughout the entire lift sequence. Vince Voetberg, Michigan Manager for Jeffers Crane Service Inc. (a Terex distributor), noted that the HC 110 remained stationary with 110 feet of main boom while the HC 165 carried 160 feet of boom and did the fine positioning adjustments.
The Role of the Rough Terrain Crane in Assist Work
In addition to the two crawler cranes handling the tandem beam lifts, C.A. Hull deployed a Terex RT 670 rough terrain crane in the 70-ton capacity class to support the operation. This crane assisted with several critical tasks:
- Helping position false decking and fascia platforms during the overnight beam lift windows
- Assisting with formwork placement on top of the new bridge decks
- Positioning rebar for the concrete deck pours
- Handling general lifting needs from the top side of the project
The RT 670’s 111-foot main boom could telescope under load, allowing it to efficiently perform multiple lift types without re-rigging. Its three steering modes reduced the turn radius, which was critical on the congested construction site where space was at a premium.
Key Lift Parameters for the US-10 Bridge Project
| Parameter | Value |
|---|---|
| Beam length | 104 feet |
| Beam weight | Approximately 43 tons each |
| Total beams placed | 32 (16 per direction) |
| Primary lift cranes | Terex HC 165 (165-ton) and HC 110 (110-ton) |
| Assist crane | Terex RT 670 (70-ton rough terrain) |
| Lane closure window | 10 p.m. to 6 a.m. (8 hours per night) |
| Closure nights | 2 (southbound then northbound) |
| Crane assembly time | Less than 5 hours per crane (4-person crew) |
| Total project cost | $6.4 million |
| Project duration | Less than 7 months |
Lessons for Bridge Contractors Using Tandem Lifts
The successful completion of the US-10 bridge replacement project offers several practical lessons for contractors planning similar infrastructure work. Every bridge replacement project presents unique challenges, but the principles that guided C.A. Hull’s approach apply broadly. The cantilever construction methods used in other notable bridge projects, as detailed in the Essential Guide to Howrah Bridge Construction of the Longest Cantilever Bridge in India, demonstrate that careful equipment selection and lift planning are universal requirements regardless of project scale.
Planning for Overnight Lane Closures
When working with interstate lane closures, every minute matters. Contractors should consider the following best practices drawn from this project:
- Pre-assemble everything possible before the closure window begins. C.A. Hull rigged both cranes and completed all final preparations before the 10 p.m. lane closure time, ensuring no time was wasted after the interstate was shut down.
- Choose equipment that minimizes setup time. The hydraulic counterweight systems on the Terex crawler cranes eliminated the need for an assist crane during assembly, saving hours of setup time and reducing overall project cost.
- Plan for redundancy in the lift sequence. The tandem approach meant that if one crane encountered an issue, the other could still safely hold its load. This built-in redundancy is a safety advantage over single-crane methods.
- Include a support crane for secondary tasks. The RT 670 handled false decking, formwork, and rebar placement, allowing the main crawler cranes to focus exclusively on beam placement without interruptions.
Equipment Selection Criteria for Bridge Beam Placement
The equipment choices made by C.A. Hull point to several important criteria for bridge contractors evaluating crane options:
- Capacity versus footprint tradeoff. A crane must provide sufficient lift capacity while fitting within the physical constraints of the jobsite. The HC 110’s narrow 18.6-foot width was the deciding factor that allowed it to operate from the median strip.
- Transport economy. The number of truckloads required to move equipment between projects affects both cost and mobilization time. Cranes that can be broken down into fewer loads offer a competitive advantage.
- Ease of assembly. Cranes that a small crew can set up quickly reduce labor costs and shorten project timelines. A four-person crew assembling both cranes in under five hours demonstrates the value of this attribute.
- Operational flexibility. The ability to telescope under load (as with the RT 670) or crawl during a lift (as with the HC 165) gives contractors options for fine-tuning beam placement without additional equipment.
In less than seven months, C.A. Hull’s crews completed the transformation of two decades-old, structurally deficient bridges into sound, modern structures carrying more than 31,800 vehicles per day over I-75. The $6.4 million investment demonstrates how careful equipment selection, meticulous planning, and tandem crane lift techniques can turn an infrastructure challenge into a project completed within tight overnight windows. For contractors facing similar bridge replacement projects, the US-10 over I-75 project stands as a practical example of what is achievable when the right equipment meets careful execution.