Full-Depth Reclamation on Water Tower Road, Hamilton County, Illinois
Project Recap: Full-Depth Reclamation on Water Tower Road, Hamilton County, Illinois
At Mt. Carmel Stabilization Group, we have built a reputation as a trusted partner for long-term infrastructure solutions, with soil stabilization being our focus for 75 years. Our recent full-depth reclamation project on Water Tower Road near McLeansboro, Illinois, is an example of that. This project wasn't just about fixing a road; it was about addressing an underlying issue that required a more thoughtful, value-engineered approach.
The Backstory: A Road with a Unique Challenge
Several years ago, we had completed a full-depth reclamation on Water Tower Road in accordance with Illinois state specifications. The project was a success overall, but there was a one-mile section that began to show signs of deterioration shortly after our initial work. This particular section of the roadway lies atop a seam of very fat clay soil, which is prone to extreme moisture retention and expansion. That underlying soil compromised the road’s durability over time.
The rest of the roadway we had previously stabilized continues to perform well, but this unique section demanded additional attention. Rather than simply revisit the standard treatment, we partnered with county road commissioners to develop a custom solution that directly addressed the root cause: the poor-quality soil beneath the road surface.
Engineering a Sustainable Solution
Understanding that the existing roadway material alone would not be enough to provide long-term stability, we proposed a specialized treatment plan to ensure the road could handle the pressures of traffic and the unique soil conditions.
Step 1: Addressing the Underlying Soil with Lime Kiln Dust (LKD)
The first step in this process was applying lime kiln dust (LKD) directly to the existing chip and seal road surface. LKD is particularly effective for stabilizing clay-heavy soils like the one beneath Water Tower Road. We used just over 250 tons of LKD to treat the affected roadway. This material was pre-pulverized into the existing road surface and immediate underlying road base to a depth of 16 inches, ensuring the LKD thoroughly mixed with both the road material and the problematic soil beneath. By the end of day one, the prepulverized material was graded and sealed with a smooth drum to set the foundation for the next phases.
Step 2: Soil Cement Treatment for Long-Term Stability
Following the LKD treatment, the next day and a half was dedicated to our standard soil cement process. We treated the road to a depth of 12 inches, ensuring that the mixture of soil, cement, and water formed a durable, stable foundation. Given the moisture-sensitive nature of the underlying clay, we made real-time adjustments to the water content.
To ensure the quality of the road stabilization, DCP (Dynamic Cone Penetrometer) testing was performed at two stations along the stretch. The results confirmed that the soil cement had achieved the required density and strength.
Step 3: Final Grading and Preparation for Surface Treatment
After the soil cement process, our grader operator completed the final grading of the surface. The operator remarked that this was one of the smoothest road surfaces we had completed this season, a testament to both the quality of our materials and the skill of our crew. The burn-off prior to the chip and seal crew applying the prime coat went off without a hitch, setting the stage for a long-lasting, smooth, and durable surface.
Why Did the Road Break Down After Our Initial Work?
It's important to address the question some may have: why did a section of this road break down after we previously worked on it? The answer lies in the unique conditions of the soil beneath that one-mile section. The fat clay soil affecting this one section of the roadway retained moisture and the shrinking and swelling that is caused by that moisture can wreak havoc on a roadway if not properly addressed. When we initially completed this project, we followed state specifications, which didn’t account for the specific soil challenges in this isolated area. The work we performed initially was sound, and the remainder of the roadway is still performing well today. However, this section required a more in-depth treatment due to the underlying soil, which is exactly what we’ve provided.
Conclusion: A Tailored Approach for Long-Lasting ResultsBy partnering with the county road commissioners and utilizing value-based engineering methods, we were able to develop a solution that not only addresses the surface issues but also resolves the core problem of the underlying soil. The combination of lime kiln dust treatment and soil cement stabilization ensures that this roadway will serve the local community reliably for many years to come.
At Mt. Carmel Stabilization Group, we don’t just fix roads; we solve problems at their source. This project highlights our commitment to delivering long-term value and customized solutions, no matter the challenges the soil or conditions may present.
