Applications for Successful Erosion Control of Slopes and Channels
Most slopes and channels fail due to the erosion of the surficial soil. The problem is that soil erosion manifests over time, ranging from days to decades, and most constructed slopes and channels treated by conventional designs and construction practices overlook this protracted aspect of soil erosion, which results in structures, slopes, and channels prone to failure. Identify the soft and hard armor solutions available for effective erosion control that ensure the longevity and stability of your slopes and channels and protect the environment.
The difference between soft and hard armor applications lies primarily in the materials and methods used, their environmental impact, and the needs of each unique project. Soft armor solutions typically involve aspects of vegetated systems, whereas hard armor solutions likely involve solutions based around materials such as concrete or aggregate.
The most common soft armor solutions include turf reinforcement mats, erosion control blankets, and bioengineering techniques that use live plant materials. These methods are environmentally friendly and aesthetically pleasing. They are typically less expensive than hard armor solutions and better suited for environments with lower flow velocities. However, they may not be as durable or effective as hard armor solutions in high water flow or wave action areas. Product examples include High-Performance Turf Reinforcement Mats (HPTRMs,) GreenArmor, and Geoweb.
High-Performance Turf Reinforcement Mats feature densely woven technology of a unique, three-dimensional matrix of polypropylene yarns. These yarns are designed in a uniform, dimensionally stable, and homogenous configuration of pyramid-like structures, specially created to lock soil in place while providing an optimal environment for vegetation to germinate. HPTRMs primary function is to provide a reinforcement matrix for roots to penetrate, locking in the vegetation and altering the system's overall performance.
HPTRMs exhibit incredibly high tensile strength and superior interlock and reinforcement capacity with both soil and root systems. They stand up to the most challenging erosion applications where high loading and high survivability conditions are required, including maintenance access, steep slopes, arid and semi-arid environments, pipe inlets and outlets, structural backfills, utility cuts, potential traffic areas, abrasion, high-flow channels and areas where more significant factors of safety are desired. Learn More.
The GreenArmor System combines engineering and agronomic excellence to create the world's most effective Green Design Engineering™ alternative. The system begins with TRM (Turf Reinforcement Mat), providing a permanent, lofty, open matrix. It is then hydraulically infilled with Flexterra® HP-FGM™ (High Performance-Flexible Growth Medium™) to intimately bond soil and seeds while accelerating growth.
This unique system protects against elevated levels of hydraulic lift and shear force while encouraging turf establishment and long-term root reinforcement—growing denser vegetation faster in areas where other TRMs have fallen short. This synergistic combination of cost-effective technologies enables the GreenArmor System to provide unprecedented levels of design safety. Learn More.
The Presto GEOWEB® system is the original 3D geocell developed by Presto Geosystems over 35 years ago. Using proven confinement technology, the GEOWEB system offers economical, effective geosynthetic design options to solve soil stabilization problems wherever land and water meet. We offer the industry's most complete geocell system, designed with ATRA® accessories that increase strength and ensure long-term performance and speed installation.
The technology of cellular confinement is powerful yet simple. Through a network of 3D interconnected cells, infill is confined and resistant to movement. The GEOWEB® system 'transforms' infill through confinement—providing strength and stabilization to cohesionless soils for various applications—from roadways to steep embankments. Learn More.
Hard armor solutions involve the use of non-biodegradable materials to protect soil surfaces. These methods are typically more robust and are used in areas with severe erosion risks. They provide excellent resistance to erosion and can handle high flow velocities, making them ideal for areas with high levels of surface runoff or in channels with significant water flow. Hard armor solutions include Gabions, HydroTurf, Concrete Canvas, GEOWEB, and Articulating Concrete Blocks.
Maccaferri gabions are cages engineered from double-twisted hexagonal woven steel wire mesh. Delivered flat-packed, our gabions are assembled and filled with stones at the project site. These modular units have numerous uses and are typically used to form flexible, permeable, and monolithic structures such as retaining walls, channel linings, hydraulic control structures, and erosion protection. They are increasingly being used in architectural applications as well.
Maccaferri gabion baskets are made from high-quality steel wire, which is heavily galvanized. An additional protective polymeric coating is also applied for gabions in more aggressive environments or where a longer design life is required. An additional protective polymeric coating is also used for gabions in more aggressive environments or requiring a longer design life. Learn More.
HydroTurf® is an engineered revetment solution designed to provide armoring of hydraulic structures against high velocity and shear stress. It offers the aesthetics of vegetation combined with better performance than traditional hard armor. It is also significantly less costly than other conventional methods.
Construction of the system is rapid, low impact, and scalable, reducing the carbon footprint. HydroTurf provides an impermeable geomembrane protected by engineered turf, infilled with HydroBinder®, resulting in a fiber-reinforced high-strength concrete matrix. HydroTurf is an economically and environmentally friendly hardened erosion armoring technology that reduces construction and long-term maintenance costs. Learn More.
Concrete Canvas® is part of a revolutionary new class of construction materials called Geosynthetic Cementitious Composite Mats (GCCMs). It is a flexible, concrete-filled geotextile that hardens on hydration to form a thin, durable, waterproof concrete layer. Essentially, it's Concrete on a Roll™. Concrete Canvas® GCCM (CC) allows concrete construction without the need for plant or mixing equipment: just add water.
Concrete Canvas is a 3-dimensional fibre matrix containing a specially formulated dry concrete mix. A PVC backing on one surface of the Concrete Canvas ensures the material has excellent impermeability. Concrete Canvas can be hydrated by spraying or fully immersed in water. Once set, the fibres reinforce the concrete, preventing crack propagation and providing a safe plastic failure mode. Concrete Canvas® GCCM is available in 3 thicknesses: CC5TM, CC8TM, and CC13TM, which are 5, 8, and 13mm thick, respectively. Learn More.
Hard Armor is a term used to describe permanent stabilization solutions, which exist in many forms, both vegetated and non-vegetated. Such solutions are indicated when water velocities in channels or ditches require robust reinforcement to prevent erosion problems.
Filter Point Concrete Linings with filtration points (drains) provide erosion-resistant, permeable concrete linings for ditches, channels, canals, streams, rivers, ponds, lakes, reservoirs, marinas, and protected port and harbor areas. Filter Point Concrete Linings have a cobbled surface and a relatively high coefficient of hydraulic friction to achieve lower flow velocities and reduce wave run-up. The filtration points provide for the relief of hydrostatic uplift pressures, increasing the system's stability. Learn More.
A type of erosion control system made from concrete connected by a series of cables or geogrids, Articulated Concrete Blocks are designed to form a flexible, mat-like cover over vulnerable areas such as riverbanks, shorelines, or slopes, protecting them from erosion.
Articulated concrete blocks (ACBs) are highly beneficial for erosion control in various environments thanks to their robust design, which is capable of withstanding harsh conditions such as high-velocity water flow and direct wave impacts. These blocks offer high strength and durability, ensuring robust erosion protection. They are flexible enough to adapt to changes in the terrain and are environmentally compatible, allowing for vegetation growth. This enhances the aesthetic appeal of the protected areas. Furthermore, ACBs are easy to install, causing minimal disturbance to the site. Their long-term stability and minimal maintenance requirements add to their appeal. Additionally, their cost-effectiveness is evident in the reduced frequency of repairs and replacements needed. Learn More.
In conclusion, selecting appropriate erosion control measures, whether soft or hard armor solutions, is critical in ensuring the longevity and stability of slopes and channels while protecting the environment. Using vegetation and organic materials, soft armor solutions offer an environmentally friendly and visually appealing approach. They are ideal for areas with moderate erosion risks and where ecological harmony is a priority. High-performance turf Reinforcement Mats, GreenArmor, and GEOWEB® exemplify this approach, offering high tensile strength, accelerated vegetation growth, and soil stabilization.
On the other hand, hard armor solutions are more suited for environments facing severe erosion challenges. These solutions utilize non-biodegradable materials like gabions, HydroTurf®, and Concrete Canvas, providing robust and immediate protection against erosion. They are particularly effective in areas exposed to high velocity and shear stress, where durability and strength are paramount.
Ultimately, the choice between soft and hard armor methods hinges on a thorough assessment of the specific site conditions, including erosion severity, terrain nature, environmental considerations, and budgetary constraints. By carefully evaluating these factors, one can determine their project's most effective, sustainable, and cost-efficient erosion control strategy. This strategic approach ensures the structural integrity of slopes and channels and contributes positively to environmental conservation and landscape aesthetics.
Faced with an under-designed earthen channel and restricted space, the City of San Antonio needed an effective and aesthetically pleasing solution. The challenge was upgrading to a concrete-lined channel that could handle increased drainage needs without compromising the look or exceeding the budget.
