Resources

Designing for Performance: Segmental Concrete Pavements

Segmental concrete pavements – interlocking pavers, permeable pavers, grids, and paving slabs – are used widely in landscape and transportation projects. When appropriately designed, constructed and maintained, segmental paving can create vibrant social spaces, manage stormwater, mitigate the urban heat island effect, increase safety, and save on capital and maintenance costs. This webinar presents information to design for and ensure long-term performance of these systems, including design considerations, assembly options, and lessons learned. Using the SITES® rating system as a framework, this session will cover tools to estimate environmental performance, as well as conduct a life-cycle cost analysis.

The goal of this project was to investigate the Wheelchair Pathway Roughness Index (WPRI) values of 96 various concrete permeable and non-permeable concrete paver surfaces in the Pittsburgh, Philadelphia/New Jersey, and Northern Virginia areas. Data regarding joint width, chamfer width, imagery, and WPRI values were collected. WPRI values were collected by pathVu’s PathMeT technology according to ASTM E3028. The results were compared against published suggested thresholds by Duvall et al. According to those thresholds, 77 surfaces performed within the acceptable WPRI range, 19 performed with the cautioned range, and 0 were found to be in the unacceptable range. A correlation between joint width, chamfer width, and WPRI was evident. Joint and chamfer width appear to be significant factors in determining WPRI.

Life-cycle costing has become an essential component of any modern infrastructure design. It has long been realized that maintenance and rehabilitation costs, not just the immediate initial construction costs should be considered when evaluating investments in similar pavement alternatives.

As part of this project, Applied Research Associates, Inc. (ARA) developed a MS Excel based life-cycle cost analysis (LCCA) tool that quantifies and incorporates some of the stormwater management and quality benefits into the LCCA to compare permeable interlocking concrete pavements (PICP) to conventional pavements including off-road benefits.

The American Society of Civil Engineers (ASCE) Foundation owns a six-story office building in Reston, Virginia surrounded by several acres of asphalt pavement for parking ~300 vehicles. The building serves as the headquarters for this civil engineering society that consists of over 100,000 members. When the asphalt pavement was in need of milling and replacement in 2018, the American Society of Civil Engineers asked its Foundation for an approach that would demonstrate the Society’s commitment to sustainable environmental design via low impact redevelopment, specifically through runoff and pollution reduction.

The ASCE Foundation reached out to Society members (including CMHA staff) and vendors to donate design time, money and materials for a demonstration retrofit project for the parking lot. This resulted in a design and donations that captured and infiltrated about half of the runoff from the asphalt parking lot. The ICPI Foundation donated the construction of permeable interlocking concrete pavement (PICP) visitor parking consisting of 17 spaces and 7 for disabled users at the entrance.