Lessons from Port of Napier’s High-Load Challenge

挑戦

For port operators and infrastructure planners, the issue is not just growth, but it is the intensity of growth and how it concentrates stress on critical infrastructure. At the Port of Napier, throughput increased significantly in the early 2000s, bringing with it heavier equipment and more frequent loading cycles.

Front-axle loads reached over 100 tonnes (110 US short tons), placing extreme pressure on pavement surfaces. Over time, this resulted in rutting up to 85 mm (3.3 in) along wheel paths; these were not surface-level concerns. The deformation disrupted operations, requiring frequent maintenance and caused instability as forklifts moved across uneven ground.

This is where we think the industry’s thinking is shifting: These types of failures are not isolated, and they reflect a broader misalignment between how infrastructure is designed and how it is actually used in high-demand environments.

解決策

Rather than continuing a cycle of reactive maintenance, Higgins, a New Zealand-based road infrastructure contractor, approached the issue from a performance-first perspective. The goal was not simply to repair damage, but to design a pavement system capable of withstanding sustained, high-load conditions over time.

Their solution incorporated highly modified asphalt (HiMA), our polymer technology engineered for durability under heavy stress. The resulting pavement structure combined 10 cm of HiMA SP28 asphalt, placed over a cement-stabilized based and 75 cm of crushed river gravel, and finished with a 5 cm SP12.5 asphalt wearing course using PG64E-22 SBS bitumen. Together, this system was designed to deliver long-term structural integrity in one of the port’s most demanding environments.

Initial implementation targeted the most heavily rutted sections of the port, with 420 square meters paved in 2010, followed by an additional 2,700 square meters later that same year. This measured approach allowed performance to be evaluated in real-world conditions before expanding more broadly.

What is important here is not just the material choice, but the mindset shift it represents, moving from maintenance –driven decisions to engineering for long-term performance from the outset.

影響

Proof That Performance Matters

Years later, the results demonstrate what is possible when infrastructure is designed to match actual operating conditions. After handling an estimated 700,00 twenty-foot equivalent units (TEUs), the trial section showed no signs of structural distress.

“Deformation is estimated at less than 5 mm, and no cracking has been observed.”

Sean Bearsley, Technical Innovation and Implementation Manager, Higgins

These results highlight a significant shift from infrastructure that degrades under pressure to infrastructure that performs reliably under it.

Scaling the Impact Across Infrastructure

The success at the Port of Napier didn’t remain isolated. Following the trail, Higgins expanded the use of HiMA across New Zealand, applying the same principles to other high-demand environments. This included state highways, municipal streets, and additional port facilities.

In total, approximately 110,000 square meters (1.2 million square feet) of pavement have since been constructed using similar approaches. This demonstrates that solution proven in extreme conditions can scale effectively, offering value across a broader infrastructure network.

For decision-makers, this is a critical takeaway. When performance is validated under the most demanding conditions, it creates confidence for adoption in more conventional applications but is still highly important.

The Bigger Lesson for Infrastructure Leaders

The Port of Napier case underscores a broader industry shift. Designing for average conditions is no longer sufficient in environments where demand continues to intensify.

Instead, infrastructure must be designed for peak loads, repeated stress, and long-term performance expectations. This requires rethinking traditional approaches and prioritizing materials and designs that minimize lifecycle costs, reduce maintenance disruptions, and improve operational efficiency.

The opportunity is not just to extend asset life, it is to fundamentally improve how infrastructure supports the systems that rely on it.