Solar farm access roads stabilized with MIRAFI RS380i

Overview

When a prominent developer and operator of renewable energy storage solutions was building a new solar site in Texas, a solution was needed to stabilize access roads used during installation. Solar farm sites are often located in remote, protected areas or agricultural land, where soil conditions can be less than ideal.

Challenge

Multiple access roads needed to be constructed to allow heavy machinery and materials to be transported to the construction site. Expansive soils, which can shift and change volume with moisture fluctuation, created challenges in stabilizing these access roads.

Solution

After evaluating various options, the engineering team chose a solution involving six in. (15 cm) of flexible base over MIRAFI® RS380i. MIRAFI RSi-Series provides a proven solution for constructing durable, high-performance access roads and platforms in solar farm projects.

Taking the soil conditions into consideration, the required reduced aggregate thickness for road stabilization was determined using the subgrade strength parameters outlined in the Giroud-Han (2004) methodology. This approach provided the necessary reinforcement for the access roads while reducing material costs, shortening the construction timeline, and ensuring long-term durability. Additionally, it minimized environmental impact by conserving resources and reducing CO2 emissions compared to traditional methods.

By utilizing the MIRAFI RS380i system, immediate site access was achieved without the need for excavation and allowed for a thinner base layer, resulting in substantial savings. The Solmax team provided onsite support during installation, visiting the site multiple times to address questions and proper installation criteria.

MIRAFI RS380i placed to reinforce access roads over expansive Texas soils.

Geotextile reinforcement installed to reduce base thickness for solar farm roads.

Access road construction accelerated using MIRAFI RS380i and flexible base

Field crew installing MIRAFI RS380i to improve bearing capacity.

Reduced aggregate layer achieved through Giroud–Han design methodology.

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