KBE facing with gabion constructions

Axel Friedhoff, Rothfuss Best Gabion GmbH & Co. KG

Definition

Facing = cladding, facing, front formation, “face”

Gabion = usually cages closed on all sides, made of welded, usually galvanised steel rods (mesh) for filling with suitable filling materials

KBE facing with gabion structures offers a wide range of natural and economical design options.

The currently applicable regulations are:

DIN EN 14475 – Execution of special geotechnical works (special civil engineering) – Reinforced fill structures, DIN German Institute for Standardisation, Berlin, 2006 edition
Recommendations for the design and calculation of earth structures with geosynthetic reinforcement – EBGEO, Verlag Wilhelm Ernst & Sohn, Berlin, 2010 edition
Information sheet on retaining and noise protection structures made of concrete elements, block layers or gabions M Gab, FGSV Verlag, Cologne, 2014 edition
DIN EN ISO 16120-2 Unalloyed steel wire rod for drawing – Part 2: Specific requirements for wire rod for general use, DIN German Institute for Standardisation, Berlin, 2011 edition
DIN EN 10223-8 Steel wire and wire products for fences and wire mesh – Part 8: Welded mesh for gabions, DIN German Institute for Standardisation, Berlin, 2014 edition

The classifications of KBE facing with gabion constructions and conditionally deformable front elements are included in these regulations. They also regulate the materials and quality control of the steel wire.

The GfG Gütegemeinschaft für Gabionen e.V. (Quality Association for Gabions), founded in January 2018, has clearly defined objectives, namely the creation of rules for transparent, permanently neutrally monitored, standard-compliant quality of gabions, starting with planning, through the definition of the materials to be used, selection of the right components, tendering, monitoring and quality assurance, to the production of gabion baskets and installation on site.

The instrument used for this is RAL quality assurance. This involves the binding definition of principles for the planning and manufacture of gabion structures, the assurance and monitoring of the quality of gabions and their building materials, and the further development of gabion construction methods. The ongoing exchange of experience and information between the members of the quality association, continuous quality assurance, the exploration of opportunities for optimising products to the highest quality standards, and assistance for companies in developing quality criteria are further tasks of the GfG Gütegemeinschaft für Gabionen e.V. (Quality Association for Gabions).

The quality and testing requirements for gabions and gabion structures differ from existing regulations mainly in that, in addition to the previous considerations in the regulations, the areas of planning and construction of structures and, as a special feature, the structure itself are defined. The existing regulations have been further developed, supplemented and adapted with the aim of improving the quality of gabions.

Some examples:

Adaptation of DIN 10223-8 with regard to the shear strength of welded joints
Consideration of the planning and construction of structures
Durability of welded mesh in relation to both salt spray testing and long-term testing
The area of filling materials defines not only the lower but also the upper sieve size

The quality and testing regulations for gabions and gabion constructions are currently undergoing the approval process by the RAL Institute. RAL quality assurance stands for greater quality, transparency and safety. Carrying the RAL quality mark requires the labelled products and services to be better than current standards or legal requirements dictate. The RAL quality assurance system is associated with a far-reaching quality promise. The system ensures the reliability, objectivity and transparency of the RAL quality mark and stands for neutrality, monitoring, independence, sustainability, cost-effectiveness and durability. Once this new quality assurance has been approved, products and services that comply with the quality and testing regulations can be awarded the new RAL quality mark for gabions.

We appreciate your interest and are happy to provide you with further information.

Rothfuss Best Gabion GmbH & Co. KG
Dr.-Oetker-Straße 30
54516 Wittlich

Telephone: 06571 / 95233-0
Fax: 06571 / 95233-55
www.rothfuss-bestgabion.de
kontakt@rbg.eu

GfG Gütegemeinschaft für Gabionen e.V. (Quality
Association for Gabions) Office
Dr.-Oetker-Straße 30
54516 Wittlich

Fax: 06571 / 95233-52
Fax: 06571 / 95233-55

www.gfg-gabionen.de info@gfg-gabionen.de

This article was first published in 2019 at the Naue Colloquium.

Geotechnical classification

Facing elements made of steel grids or gabions form the visible, load-bearing front of many geosynthetic-reinforced soil walls and steep slopes and strongly influence deformation behaviour, serviceability and durability.
The mechanical performance of the steel mesh (wire diameter, mesh geometry, type and strength of joints, corrosion protection system) governs the safe transfer of earth pressures, traffic loads and superimposed loads such as railings or noise barriers.
Only a coordinated interaction between facing, geosynthetic reinforcement and backfill with defined tolerances for dimensions, flatness and connection details ensures reliable force transfer and controlled deformations.
For permanent structures, exposure conditions (e.g. frost–de-icing salts, fluctuating water levels, chemical attack) and the required design service life result in project-specific requirements for steel quality and coating thickness.
The grading and durability of the gabion or facing infill as well as the surface structure of the facing affect erosion resistance, drainage behaviour and the potential for sustainable greening of the front.
Standards and recommendations (e.g. DIN EN 14475, EBGEO, DIN EN 10223-8) together with RAL-based quality and testing regulations provide a framework for reproducible material properties, factory production control and long-term performance of gabion structures.

Typical project questions

Which corrosion protection systems, steel grades and mesh parameters are necessary for the specified exposure class, design working life and safety level of the reinforced soil structure?
How should facing elements, geosynthetic reinforcement layers and backfill be detailed so that load transfer, deformation limitation and staged construction can be implemented robustly on site?
Which additional geosynthetic components are required for filtration, drainage and surface erosion control so that the combination of facing, reinforcement and soil remains permanently functional?

Suitable Naue products & system solutions

A project-specific system selection enables protective structures to be implemented efficiently, durably, and tailored to local conditions.

Reinforced soil walls with steel grid or gabion facings

Secugrid® m3 systems (reinforced soil) for mechanically stabilised earth structures with steel mesh or gabion facings, providing high tensile stiffness, defined facing connections and verifiable long-term strength for steep slopes and walls.
Secugrid® Geogrids as reinforcement layers in the backfill to mobilise soil resistance and limit facing movements under earth pressure, traffic loads and additional superimposed actions.

Surface erosion control and greening of the facing

Secumat® erosion control systems to stabilise the soil surface in front of and between steel grids, reduce scouring and support durable vegetation on steep, highly loaded slopes.
Secutex® nonwoven geotextile as a filter and separation layer between soil, erosion control systems and gabion infill, maintaining long-term filter stability and protecting sensitive elements from damage.

Drainage behind facing elements

Secudrain® drainage mats to collect and discharge seepage and surface water behind the facing, reduce pore water pressures and limit frost- and water-induced deterioration of steel grid structures.
Secutex® nonwoven geotextile as a protective and filter layer in conjunction with drainage mats, preventing soil intrusion into drainage cores and preserving discharge capacity.

Sealing and base stability of embankments and noise barriers

Bentofix® GCL for mineral sealing elements at the toe or base of dams and noise protection embankments where additional groundwater protection or containment of contaminated material is required.
Carbofol® geomembrane as a high-performance geomembrane for base sealing or back-of-structure waterproofing in areas subject to elevated hydraulic gradients or contamination.

Notice: This page was translated automatically. If anything seems unclear, please refer to the German version.
Quality requirements for facing elements made of steel grids