G2 Completes I-75/M-46 Work in Saginaw County

G2 Consulting provided geotechnical investigations, vibration monitoring, geotechnical instrumentation services, and pile dynamic analysis for the project which will reconstruct and widen a segment of I-75. In fact, the last segment between Flint and Saginaw to be expanded to four lanes in each direction. The project also replaces the aging M-46 interchange and renovates bridge structures in the area.

“Every project has its own unique characteristics,” said Christopher Nicol, P.E., G2’s Project Manager. “One interesting aspect of this project was the need to fill in a ‘dip’ in I-75 that previously allowed the highway to pass underneath a railroad bridge, a bridge that has long since been removed.”

“Highway dips and other low-points are natural gathering spots for storm water therefore require pump stations to keep the roads open to safe travel,” Nicol said. “Since the railroad overpass is no longer there, bringing I-75 back to grade was an important improvement to avoid impediments to travel and the costs associated with pumping.”

Under MDOT’s guidance, G2’s activities were managed by Grand Rapids-based Fishbeck and Commerce-based C.A. Hull in the design-build effort.

“The Michigan road industry has learned a lot of valuable lessons over the recent ‘lean’ years where underfunding was the norm. There has been constant innovation in road evaluation, construction processes and material technologies. Now that infrastructure needs are top of mind and meaningful funding is on the way, Michigan has both the public and private engineering and construction capabilities to get the jobs done efficiently and effectively,” Nicol said.

G2’s geotechnical work focused on analyzing and evaluating below-the-road factors — soil and pavement conditions, drainage, and the level of deterioration a road has experienced over a time period — to determine the best approach to reconstruction within the specific environment. This information is key to prudent decision making and often impacts final design. Considerations include the amount of traffic using the road and predictive models for future deterioration. With the huge amount of work that needs to be done across Michigan communities, construction partners need to work intelligently to get the most out of every dollar spent.

Although G2’s portion of the project is nearly complete, the overall project is expected to last into July 2022. The team has largely held to its schedule, despite the summer’s heavy rains which, at times, hampered progress. G2 lives by its mantra of “Smart. Results. Fast.”


Job One: Understanding Site Conditions

Doing it right the first time is a concept that could well apply to G2 Consulting Group Project Managers who spend much of their time evaluating subsurface conditions for new construction project sites throughout Michigan and 30-plus other states.

Since the results of the initial geotech and subsurface exploration will affect everything else in the project, and how it’s built, it’s absolutely critical information that requires experience-based knowledge and often specialized focus to provide the most cost effective recommendations for development.

Determining, understanding, and evaluating soil properties through the eyes of an owner, contractor, and designer is how G2 Consulting Group started in business more than 25 years ago and remains a central focus of the firm’s business today. It’s not glamorous work, for sure, but it is the first thing done in every construction project on the planet. And in many ways, the most important.

For contractors and developers starting a project, it’s important to partner with an engineering firm that doesn’t “just do” geotechnical work. Better to choose a firm where geotech services are a core competency, a company that fully understands best practices and also understands how these conditions impact the overall constructability of an entire project. It’s this technical understanding of the overall project and of the composition and expected behavior of what’s going on below the ground that is often the difference between a successful project versus one with “surprises” and costly change orders.

In-depth evaluation of the project begins in the proposal phase, evaluating both historical and current aerial photographs, elevations, and surrounding properties which may influence the project. This allows the correct placement and number of borings to be performed to best benefit the client in obtaining a thoroughly and properly thought out geotechnical investigation.

“Geotechnical work is Job One on every construction site but it’s usually a miniscule part of an overall project’s cost,” says G2 Project Manager Amy Schneider.  “It is absolutely not the place to cut costs. In fact, a comprehensive and pragmatic geotechnical investigation can often lead to lower overall construction costs by more accurately determining issues ahead of time which may result in higher construction budgets .

Whether its understating the soil, rock, and groundwater data, or creating the design parameters for your project’s footprint, foundation and construction methods, the geotechnical investigation absolutely sets the tone for the rest of the project.

“Spending a few more dollars up front with the right company can pay huge dividends in completing the overall project on time and on budget. That’s what G2 is in business to help our clients do,” Schneider said.

G2 has completed more than 10,000 geotechnical investigations and prides itself both on its institutional knowledge and its understanding of the larger construction challenges required to bring a project to life. The firm works on a wide range of projects including: commercial, residential and industrial structures, roadways, bridges, dams, slopes, retaining walls, and communication towers.


G2 “Maps It Out” For Tower Owners/Carriers

As available tower space becomes more limited, it becomes imperative to tower owners and carriers to make the most of the existing space that is available. Oftentimes, this involves performing a structural analysis of the tower to determine its load carrying capacity and ability to support additional antenna structures. The existing foundation must be evaluated as part of this structural analysis.

What happens when the original foundation plans, geotechnical report, or as-built plans are not available? At this point it becomes necessary to perform an investigation to determine the subsurface conditions at the site and foundation type and dimensions. G2 has performed hundreds of such investigations across the United States for numerous clients including Semaan Engineering, Fullerton Engineering, Terra Consulting Group, W-T Communication Group, and all the major telecommunication tower owners and carriers.

G2 has the ability and network of drillers across the country to perform geotechnical investigations almost anywhere. Typically, our foundation investigations utilize low-strain pile integrity test methods to evaluate drilled piers. We also utilize excavation methods, as necessary, to determine foundation information. Our past investigations have also included evaluation of guyed anchor bars for corrosion below grade.

We also maintain a database of the thousands of tower sites we have worked on over the past 20 years and may be able to locate previous geotechnical reports or foundation designs, potentially saving a substantial amount of time and money required for new investigations.

READ:  Analysis of Existing Tower Foundations


G2 Chicagoland Recommends CCDD Services

Efficient Process Saves Time and Reduces Costs

Addressing soil characterization during the Geotechnical Investigation phase saves our clients time and money by certifying the soils during the early stages of the planning process. G2 recommends Clean Construction and Demolition Debris (CCDD) services to minimize additional expenses. CCDD is defined by the Illinois Environmental Protection Agency (EPA) as ”uncontaminated broken concrete without protruding metal bars, bricks, rock, stone, reclaimed asphalt, and soil generated from construction and demolition activities.”

Disposal of soils that cannot be utilized on site during grading is significantly less expensive at a clean fill facility. Analyzing soil and having certification forms in place early in the project stage helps remove potential delays and unplanned costs. Once site development begins, potential costs arise from stockpiling soils on site while waiting for lab results. These soils may then need to be disposed of at a regulated landfill.  Further, owners can utilize this information to obtain favorable pricing from contractors when their projects bid.

G2 Consulting Group reviews available environmental reports, as well as readily available information within the Illinois EPA’s databases to determine if there are significant environmental issues associated with the subject property or immediate adjoining properties.  Based on our review, we determine an appropriate number of soil samples and locations, as well as a scope for analytical testing parameters.

Soil samples are obtained during drilling operations performed in conjunction with our Geotechnical Investigation using proper environmental sampling protocol. Soil at the project site is visually assessed and screened in the field using a photo ionization detector (PID). Soil samples are selected for analytical testing based on visual observations, PID screenings, or using other pertinent data from our review.  Representative samples are selected and submitted to an accredited laboratory for analysis and comparison with the Illinois EPA’s “Maximum Allowable Concentrations of Chemical Constituents in Uncontaminated Soil Used as Fill Material”.  This analysis is used to determine if soils at the site meet the Illinois EPA’s criteria for disposal at a CCDD facility. Provided the material is determined to be non-impacted, a licensed Professional Engineer completes the Illinois EPA Form LPC-663 certifying that the soils are non-impacted.  It should be noted that final acceptance of the material is up to the individual landfill facility.