Written by: Bryan Wedin, P.E., Chief Design Engineer
Road construction is booming, and this trend is expected to remain strong due to high demand and the Infrastructure Investment and Jobs Act (IIJA), which includes investments across many sectors, including public infrastructure.
Along with this boom, the road construction industry has been dealing with inflation-related cost increases and limited availability of construction materials. The industry has been impacted by supply-chain interruptions and shortages for many roadway materials including lime, cement, and even aggregate. These materials are typically used for roadway base construction, which means road construction projects that use these materials may be subject to delays. Due to these shortages and delays, on-site material or sand-filled GEOWEB® geocells can provide a cost-effective, readily available substitute for base materials–especially where native subgrade conditions consist of weak or soft soils.
Sand-Filled Geoweb Geocells for Soil Stabilization
Geocells are three-dimensional honeycomb-like structure made of ultrasonically welded strips of HDPE that confine infill material over a specified cell depth and diameter. Through confinement, the GEOWEB system distributes loads laterally and controls shearing, as well as lateral and vertical infill movement.
Compared to planar geosynthetic products such as geogrids—which commonly rely on expensive imported high-quality aggregate—geocells are highly versatile and can be filled with a variety of commonly available and economical infill materials, including sand.
In many cases, geocells allow for the beneficial reuse of on-site materials, eliminating the need to purchase expensive aggregate or imported structural fill. These advantages not only offer the potential for savings in overall construction costs but also contribute to a significant reduction in carbon emissions due to less aggregate/fill processing, transportation, and handling.
The illustration below provides a comparison of four structurally equivalent aggregate sections over a subgrade with a CBR of 0.5%.
As shown, the unreinforced aggregate option would require more than 36 inches of aggregate to achieve minimal stability, and the planar geosynthetic option (geogrid + geotextile) would require 26 inches of aggregate. In contrast, the GEOWEB geocells reduce the total section thickness to only 15 inches, and where suitable on-site material is available, it is possible to limit imported aggregate to just the wearing course.
The GEOWEB geocells dramatically increase the shear resistance of the infill, which allows the use of lower-quality fill to carry concentrated loads that would otherwise require crushed aggregate to prevent localized, near-surface shear failure. The cellular structure also distributes concentrated loads to surrounding cells, thus reducing the stress on the subgrade directly beneath the load and the required total thickness of the structure.
See the Cost Savings for Yourself
Presto Geosystems’ engineering team works closely with you to provide free project evaluations and on-site installation support. The team at Presto Geosystems is here to provide engineering support from the preliminary stages through construction. Use our free online tools to keep your projects moving forward. The project evaluation will deliver a technically sound, cost-effective solution based on four decades of accredited research and project experience. Please contact our knowledgeable staff and network of qualified distributors to discuss your project needs today.
Request a free project evaluation: https://www.prestogeo.com/free-project-design/