Investing in the future: Building 100-year pavement foundations

The road to 100-year pavement foundations

The condition of America's roads reflects a growing crisis. Decades of underinvestment and reactive maintenance have led to a system riddled with potholes, cracks, and structural weaknesses. The 2025 ASCE Report Card on Roads paints a concerning picture, highlighting the urgent need for a paradigm shift towards proactive, long-term pavement solutions. We can no longer afford to simply patch and repair; we must build for the future.

The high cost of inaction

The consequences of neglecting our road infrastructure extend far beyond mere inconvenience. The economic ramifications are substantial, impacting individual drivers, businesses, and the national economy as a whole:

• The driver's burden: It is estimated that the impact of poor road conditions is costing the average driver $1,400 a year in maintenance costs and wear and tear. It is also estimate that the average U.S. driver lost 43 hours to traffic congestion in 2024 – about one full work week.

• Potholes' billion-dollar impact: The humble pothole is anything but insignificant. Collectively, potholes cost US motorists a staggering $26 billion annually, a figure that continues to rise with each passing year.

• The looming funding gap: The most alarming statistic is the $684 billion funding gap projected to 2035. This shortfall threatens to accelerate the deterioration of our roads, creating a vicious cycle of neglect and decay. An average annual investment of $151.1 billion is needed until 2038 to close this gap.

• Soil-related challenges: Pavement rehabilitation becomes exponentially more expensive in areas with expansive or frost-susceptible soils. These challenging conditions can increase rehabilitation costs by 20-30% and 10-20%, respectively, demanding specialized and resilient solutions.

TRB's vision for pavement longevity

The Transportation Research Board (TRB), in its Circular E-C296, outlines a clear vision for achieving 100-year pavement foundations. This comprehensive approach emphasizes:

• Prioritize sustainability and resiliency: Every pavement project should prioritize long-term performance, environmental responsibility, and the ability to withstand future challenges like climate change.

• Quantify geomaterials: A cost-benefit analysis of geomaterial stabilization materials, particularly geosynthetics, is essential to justify their use and maximize their impact.

• Use geosynthetics: Geosynthetics and other stabilizing materials should be strategically deployed to enhance pavement durability, provide adequate structural support, and ensure a uniform foundation, minimizing weak points.

• Designing durable foundations: Pavement foundation design must incorporate durable and resilient geomaterials coupled with effective moisture control strategies to prevent premature failure.

• Incorporate effective drainage: A comprehensive assessment of the long-term costs and benefits of constructing and maintaining durable foundations with effective drainage systems is crucial for making informed investment decisions.

Understanding the root causes of pavement failure

To build truly durable pavements, we must first understand the underlying causes of failure. The FHWA's NHI Course No. 132040, Geotechnical Aspects of Pavements, highlights several key factors:

• Subgrade soil intrusion: The migration of fine-grained subgrade soil into the base layer can significantly weaken the pavement structure.

• Excessive traffic loads: Repeated heavy loads can cause fatigue and deformation, leading to cracking and rutting.

• Surface fatigue: Constant wear and tear from traffic and environmental factors can lead to surface deterioration.

• Settlement and volume change: Unstable subgrades can settle or expand, causing pavement distress.

• Freeze-thaw cycles: In colder climates, the expansion and contraction of water within the pavement structure can lead to cracking and heaving.

• Inadequate drainage: Poor drainage allows water to accumulate within the pavement layers, weakening the structure and accelerating deterioration.

MIRAFI H₂Ri : A comprehensive solution for 100-year pavements

MIRAFI® H₂Ri offers a holistic approach to pavement design, directly addressing the key factors that contribute to premature failure. This innovative geosynthetic solution focuses on:

• Effective separation: Preventing the upward migration of fine-grained subgrade soil into the aggregate base, preserving the base's structural integrity.

• Structural reinforcement: Providing lateral restraint and increasing the load-bearing capacity of the pavement, distributing stress and reducing deformation.

• Active moisture management: Continuously controlling and removing excess moisture from the pavement structure, enhancing stability and preventing water-related damage.

The transportation research Board’s Circular on Foundation Design and Construction for 100-Year Pavement Systems recognizes the importance of these functions, mentioning separation 7 times, reinforcement 8 times and moisture/water/drainage more than 240 times.

The importance of active moisture management in roads

Moisture is a pavement's silent enemy. Excess water weakens the structure, accelerates deterioration, and contributes to a range of problems. MIRAFI H₂Ri tackles this challenge head-on, enabling Active Moisture Management through:

• Saturated and unsaturated drainage: Removing water effectively in both saturated conditions and unsaturated conditions.

• Zone of hydraulic influence: Creating a zone of influence that extends throughout the base course and subgrade, drawing moisture away from critical areas.

• Overcoming negative gradients: Draining water even when the natural gradient opposes the flow, ensuring complete and effective moisture removal.

Real-world success: MIRAFI H₂Ri in action

The effectiveness of MIRAFI H₂Ri has been demonstrated in numerous projects across diverse environments:

• MoDOT I-64 Boone Bridge: A testament to cost-effectiveness, this project achieved a remarkable 10% reduction in overall roadway costs.

• Dalton Highway, Alaska: Confronting extreme conditions, MIRAFI H₂Ri saved a significant $2.5 million in construction expenses on this critical transportation artery. Link to case study

• CSAH 10 – Norman County, Minnesota: As a sustainable alternative to chemical treatments, MIRAFI H₂Ri lowered project costs by an impressive $600,000.

Conclusion: A call to action for sustainable infrastructure

Building 100-year pavement foundations is not merely a technical challenge; it's a strategic imperative. By embracing innovative solutions like MIRAFI H₂Ri and prioritizing sustainability, resilience, and proactive maintenance, we can create a road network that serves our communities for generations to come. It’s time to invest in the future, one pavement at a time.

Solmax has developed InfraSolve®, a user-friendly design suite of software, to help put 100-year pavement foundations in action. This tool integrates proven design methods with sustainable best practices to design more resilient roadways. Click here to give InfraSolve a try.