Posts Categorized: GEOWEB Geocells Soil Stabilization System

Advancing Rail Resilience: How Geosynthetics Help Achieve CRISI Objectives for Robust and Stable Infrastructure

Discover the Latest CRISI Rail Infrastructure Funding Opportunities: Apply Before the May 2024 Deadline   The U.S. Department of Transportation is bolstering rail infrastructure advancements through the Consolidated Rail Infrastructure and Safety Improvements (CRISI) program. With a recent allocation of $2.47 billion, the CRISI program is set to significantly impact rail safety, efficiency, sustainability, and reliability across the United States. This funding initiative is designed to support a variety of projects that are pivotal to enhancing the nation’s passenger and freight rail systems. It represents a call to action for rail industry professionals, including engineers, planners, and project managers, to leverage this opportunity to advance their rail infrastructure projects. The deadline for application submissions is 11:59 p.m. ET, May 28, 2024. Professionals in the rail sector are urged to prepare their proposals that align with CRISI’s mission to improve the rail infrastructure’s overall landscape. For a comprehensive overview of the application process and to assess project eligibility, stakeholders are encouraged to review the Fiscal Years 2023-2024 Notice of Funding Opportunity (NOFO) available through the CRISI program. This funding presents a pivotal chance for those involved in rail infrastructure to gain the support and resources needed to propel their projects forward…. Read more »

Using Geosynthetics to Stabilize Soils in a Harsh Environment

By Dhani Narejo, PE, Bruno Hay, and Bryan Wedin, PE Mine Site Erosion Problems One of the largest nickel mining sites in the world is located on the South Pacific island of New Caledonia. Due to the size of the mining project and the terrain of the site, significant cut-and-fill work for civil engineering structures was unavoidable. Given the magnitude of the site, the challenge of safeguarding the structures against erosion is formidable. Inaction is not an option due to the sensitive nature of the structures, environmental concerns, and a keen desire by the owners to protect the environment. A typical example of the erosion at the site is the slope in Figure 1. Such slopes require continuous maintenance if the erosion problem is not addressed. In some cases, erosion can cause interruption in the mobility of materials and personnel at the site. Several erosion-control measures had been successfully used at the site, including riprap and concrete. An alternate erosion control system was desired by the owner that would meet the following objectives: Be cost-effective, Require little or no maintenance, Utilize local labor and materials, Have a design life exceeding 50 years. Soil, topography, weather Ultrabasic soils cover about one-third… Read more »

Geosynthetics and PFAS: Understanding the Role of Polymer Processing Aids in Geosynthetics

Written By: Michael Dickey, P.E., Director of Presto Geosystems Like many other industries, geosynthetics manufacturers are navigating the rapidly evolving landscape of new per- and polyfluoroalkyl substances (PFAS) regulations. However, in the case of geosynthetic products, an interesting and seemingly paradoxical question emerges: Is it possible that the same products that have been designed to solve complex environmental problems, and even contain pollutants, could also be a possible contributing source of PFAS? In this article, we explore this question and discuss the historic role of polymer processing aids (PPAs) in the production of geosynthetics. What Does Intentionally vs Unintentionally Added PFAS Mean? Since the discovery of PFAS in the 1930s, these compounds have been widely used in manufacturing operations worldwide—both intentionally and unintentionally. In a recent article published by the American Bar Association, the concept of intentional versus unintentional use of PFAS is discussed, and in the case of the latter, the use of fluorinated PPAS used in thermoplastics processing is highlighted as a well-known unintentional PFAS source. How this concept relates to traditional geosynthetics manufacturing is discussed further below. Eliminating Polymer Processing Aids (PPAs) from Geosynthetics Production of geosynthetic products such as geogrids, geomembranes, and geocells commonly involves sheet… Read more »

Seven Key Factors to Choosing the Right Geocell

Written by William G. Handlos, P.E. Choosing the Right Geocell Does excellent quality and support matter to you? Of course it does. But, you are smart enough to know that there is no free lunch. Low cost alternatives are less expensive for a reason. So, what do you need to look for to recognize the right geocell for your project? 1.  Quality Feedstock Insist upon verifiable proof that your geocell is manufactured only with virgin high density polyethylene. While it is possible to achieve poor weld strength with virgin materials, it is impossible to achieve consistently excellent weld strength unless only virgin high density polyethylene is used. 2.  Integral Components Choose a geocell that offers connection components, tendons, stakes, load transfer clips and installation tools that are specifically tailored for the system. Using rope, staples, bent rebars (J hooks) and zip ties that are not specifically designed for use with a geocell engineered solution is unwise and potentially catastrophic. Use only designs that recognize the critical nature of these components to the overall success of the project. 3.  Experience and Warranty Choose a manufacturer who has thousands of projects and decades of experience. It is shocking how little some manufacturers… Read more »

Are material shortages delaying your road construction projects? Here is how to stay on schedule and within budget.

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. GEOWEB® Geocells for Roadway Base Stabilization The GEOWEB geocells have been used for load support and foundation applications worldwide for more than 40 years. Developed in collaboration with the U.S. Army Corps of Engineers (USACE) in the late 1970s, Presto co-invented the technology now known as geocells or a cellular confinement system (CCS). The early applications of geocells consisted primarily of stabilized, expedient… Read more »

How Geosynthetics Are Uniquely Poised to Help Alleviate Congestion at U.S. Ports

Written by: Michael J. Dickey, PE, Director and Bryan Wedin, PE, Chief Design Engineer On May 6, 2022, the Maritime Administration (MARAD) released an amended Notice of Funding Opportunity (NOFO), allocating over $234 million for port infrastructure development in 2022. Adding to the previously appropriated amount of $450 million from the Infrastructure Investment and Jobs Act (IIJA, or Bipartisan Infrastructure Law), this will bring the total amount available for port improvement projects to $684 million for FY2022. The significance of this investment comes at a crucial time. According to the American Association of Port Authorities, the pandemic has laid bare the need for a transport system that is able to surge and stretch across all links—from sea, to land, to rail, to warehouse, to consumer. The question is, how can this funding be used to meet this need quickly and cost-effectively? The answer may lie in a strategy implemented in 2021 in the state of Georgia to alleviate congestion at the Port of Savannah. The Georgia Port Authority, in partnership with Norfolk Southern, implemented a solution that has caught the attention of other U.S. port authorities and Class I railroads using what is being referred to as “pop-up container yards”…. Read more »

Protecting Environmental Geomembrane Covers With Suspended GEOWEB Geocells

Economic pressure, the desire for green solutions, and the intensification of climate extremes have converged to create a need for better methods to effect soil stabilization. Fortunately, a proven technology exists that addresses issues associated with these conditions and provides a more stable cover solution for landfill covers, lagoons, stormwater containment basins, and other geomembrane-covered systems. Soil, aggregate, and concrete protective covers over geomembranes can be secured against known gravitational, hydrodynamic, and seismic forces using the GEOWEB® Soil Confinement System. Soil and aggregate are commonly used as a protective cover over liners on slopes of 3H:1V or less. However, when slope gradients are greater, unconfined soil and aggregate covers are typically unstable and not used. In arid areas, cover depth may range from 75 mm (3 in) to 150 mm (6 in). Where conditions support vegetation, cover depth may range from 100 (4) to 600 mm (24 in) or greater where the final depth is a function of the characteristics of the desired vegetation. Regardless of cover depth, if an extreme rainfall event occurs that is 10%, or greater than what would typically be expected, soil mass increases, assumed friction angles decrease, and factors of safety for soil stability drop to… Read more »

Solar Installations on Closed Landfills: Using Geosynthetics to Overcome Redevelopment Challenges

Written by: Michael Dickey, P.E. (WI, FL, GA, NC), Director Redevelopment of closed landfills and capped solid waste sites represent a unique opportunity for landfill owners, solar developers, and communities to work together to put underutilized properties back into productive use. Moreover, many such sites are conveniently located near existing transmission infrastructure and may be easier and more economical from an interconnection standpoint than rural greenfield sites. However, building over a closed landfill poses unique challenges because most landfills are covered by an engineered cap not typically designed to support loads from permanent foundations or heavy equipment. Additionally, state and federal regulations generally prohibit any activity that could potentially breach or damage the cap. Therefore, retrofitting a closed landfill for utility-scale or community solar projects requires careful planning. Ultimately, the project must not jeopardize the intent of the original cap design; that is, to protect human health and the environment. Selecting a Suitable Foundation Concrete slabs and pre-cast ballast footings are both foundation options for solar system installations on landfill caps. In general, concrete slab foundations are heavier than ballast footings and pose a higher risk of creating landfill settlement and side-slope stability issues. Ballasted footings are a lighter-weight option… Read more »

The History of Geocells

Geocell technology has come a long way over the past four decades. In its early days of development, the geocellular soil confinement system consisted of wax-coated craft paper; a plastic drainage pipe matrix fastened with staples; paper-thin, hexagon-shaped, glued aluminum; low- and medium-density recycled materials; pure polyethylene without UV stabilization; and square cells similar to old-fashioned egg carton separators. The Invention of Modern Geocell Technology In the late 1970s, the U.S. Army Corps of Engineers (USACE) contacted Presto Products Company—a private-label consumer packaging manufacturer—to develop a more robust honeycomb-shaped confinement system that would maintain load-bearing strength under heavy vehicle loads. Working with Steve Webster at the Waterways Experiment Station (WES), Presto’s Gary Bach devised a method to weld polyethylene strips to form a cellular structure. This innovative system became known as Sandgrid and was used by the military primarily for road applications. After the development of Sandgrid, Presto Products created a new business unit to focus solely on the geosynthetics business. With this expansion, Presto Geosystems® was established. Presto Geosystems and the USACE tested various resin blends and concluded that virgin high-density polyethylene (HDPE) provided superior weld consistency and structural strength. Presto Geosystems introduced the GEOWEB® Cellular Confinement System (CCS)… Read more »

Advancing the Mining Industry’s Transition to Sustainable Practices with Geosynthetics

Written by: Michael Dickey, P.E. (WI, FL, GA, NC) Mined materials are essential to our everyday lives. We use these valuable minerals in nearly every sector of the economy—they are necessary to construct roads and buildings, manufacture vehicles, build computers, and generate electricity. Additionally, the mining industry stimulates economic growth by providing employment opportunities and generating tax revenue that helps fund vital public services, such as hospitals and schools. As the mining industry navigates environmental, social, and governance (ESG) issues, there is a sense of urgency to adopt sustainable or “green” mining practices. Green mining can be defined as technologies, best practices, and mine processes that are implemented to reduce the environmental impacts associated with the extraction and processing of metals and minerals. The Mining Industry Faces Unique Challenges When it comes to sustainable development, operation, and closure of mines, the industry faces myriad challenges—not the least of which are poor soil conditions, weak subgrades, and other geotechnical challenges that can complicate miners’ efforts to meet ESG goals. In this regard, some of the more common geotechnical challenges that mine operators must contend with include: Constructing and maintaining heavy-duty haul roads. Stabilizing and protecting slopes. Tailings management and site reclamation…. Read more »