Scour protection: geosynthetic systems against sediment erosion | Naue | Naue
Prevent scour
Geosynthetic systems for offshore foundations, harbours, and bridge piers in flowing waters or for the toe of revetment system
Scour protection in hydraulic engineering describes the measures and structures used to prevent or reduce the erosion of sediment around offshore foundations, harbour facilities, bridge piers, and other hydraulic structures caused by flowing water, waves, and currents. Unprotected surfaces are subject to progressive material removal that undermines foundations or destabilises e.g. quary walls. Naue Secutex® Soft Rock geotextile sand containers and nonwoven filter layers stop scour at the source: reliably, durably and in compliance with international hydraulic engineering standards.
Stabilisation of beds and harbour structures against erosion and scour caused by flowing water, wave attack and tidal forces.
Secutex® Soft Rock geotextile sand container, Secutex® H filter geotextile
EAK, GBB, BS 6349, PIANC, CIRIA C742; EN 13251
Scour protection of offshore foundations, e.g. for windfarms, bridge piers, existing harbour quarry walls, river banks, coastal revetments
Scour protection: engineering challenges, geosynthetic solutions and measurable results
Challenges
Wave attack, tidal forces, near bed flow velocities and ship induced flow velocities displace unprotected sea bed or fill material
Hydraulic loads undermine structure foundations
Bridge pier scour and scour effects of offshore foundations lead to structural failure
Conventional rip-rap requires heavy plant and large quarry volumes
Offshore underwater installation in flowing water is difficult and costly
Solution
Secutex® Soft Rock geotextile sand containers (GSC) as flexible, fill-on-site scour protection solution
Integrated scour flap (SF) of GSCs Secutex® Soft Rock prevents undermining of GSC structures
Complete system from one supplier: geotextile sand containers and the filter layer if required
Result
Flexible armour self-adapts to scour geometry without loss of protection
Local sand fill reduces quarry transport and time compared to bulk quarried stone
Proven in coastal and riverine projects across multiple climate zones worldwide
Scour protection applications in hydraulic engineering
Naue scour protection solutions are deployed wherever hydraulic forces threaten bed stability, bank integrity and infrastructure foundations.
River bank protection
Protects river embankments against current-induced erosion, scour and undercutting
Coastal revetments and dyke toes
Absorbs wave energy and prevents progressive dyke toe erosion in exposed coastal settings
Bridge piers and abutments
Stabilises bed material around bridge foundations subject to flow acceleration and scour hole formation
Flood protection structures
Prevents retrogressive erosion and scour formation at the waterside face of flood barriers
Robustness and installation safety
Scour protection systems must perform under dynamic hydraulic loading from day one. Secutex® Soft Rock geotextile sand containers (GSC) are engineered for exposed coastal and riverine applications. Needle-punched nonwoven construction provides abrasion resistance. Rounded edges prevent fluttering under wave attack. The open GSC side or retractable filling trunks allow on-site filling with locally available sand.
The dimensioning of scour protection systems follows recognised hydraulic engineering standards. A digital design tool supports project-specific system selection based on flow velocity, wave height, water depth and subgrade characteristics.
Protects offshore foundations, platforms, jetties and port structures against tidal scour
Practical advantages:
Abrasion-resistant needle-punched nonwoven and double-seam construction (three sides) ensure container integrity under sustained hydraulic load.
An open GSC side or retractable filling trunks (pre-manufactured) allow on-site sand fill.
Integrated scour flap covers scour ridges without manual intervention.
System approach: filter, separation and armour from one supplier reduces on-site interfaces and coordination effort.
Filter and separation – when is each required?
A scour protection system fails if the underlying filter layer is compromised. Hydraulic gradients drive fine particles from the subgrade into the armour layer or flush them from beneath. A properly designed geotextile filter prevents this migration while allowing water drainage. The filter must satisfy simultaneous retention, permeability and clogging criteria to EN 13251.
Key principle: Scour armour resists surface erosion. The geotextile filter and separation layer protects the structural integrity of the system foundation.
Scour armour + separate filter/separation layer
Secutex® Soft Rock as scour armour layer
Secutex® nonwoven as separately specified filter and separation layer beneath armour
Core advantage: two independently optimised layers for complex hydraulic and geotechnical criteria
Secutex® Soft Rock containers provide integrated filter/separation function via the nonwoven fabric
Grand RS variants (double-layer nonwoven/woven composite) provide enhanced robustness for extreme exposure
Core advantages: fewer installation layers, fewer site interfaces, faster construction programme
Decision guide: Secutex® Soft Rock R, Grand R or Grand RS?
Product selection depends on exposure class, container volume, scour flap requirement, nonwoven construction and use case. Naue specialists as well as a question-guided digital SolutionFinder are available to support your selection process.
Criterion
Secutex® Soft Rock R 801
Secutex® Soft Rock Grand R 1201/1601
Secutex® Soft Rock Grand RS 1201/1601
Exposure class
Moderate hydraulic loading; standard riverine or coastal
High hydraulic loading; wave attack; exposed coastal structures
Very high / extreme loading; offshore; port structures
Container volume
1.2 m³ (1 filling trunk)
2.5 m² container (2 filling trunks)
2.5 m² container (2 trunks; composite nonwoven/woven)
Scour flap (SF)
Yes – Secutex® R 601 flap on longitudinal side
Yes – Secutex® R 601 flap (3.05m × 2.60m)
Yes – Secutex® R 601 flap (3.05m × 2.60m) on RS variants
Offshore; port; extreme wave energy dissipation zones
Why engineers, project managers and procurement specify Naue scour protection
Planners and engineers
Geotextile sand containers adapt to irregular seabed and riverbed geometry. The integrated scour flap covers scour ridges automatically without design revision. Filter and separation functions comply with EN 13251. The system follows hydraulic design standards including EAK, GBB and PIANC.
Project managers, ite engineers and contractors
Local sand fill eliminates quarried rock dependency and reduces transport cost. Containers are delivered flat-packed and filled on site via pre-manufactured retractable filling trunks. Units are positioned by hand, excavator or crane. The system is suitable for above-water and underwater installation.
Long-term durability: asset life performance
Double-seam technology and abrasion-resistant nonwoven ensure service life from moderate riverine to extreme coastal environments. The self-adapting scour flap reduces reactive maintenance. UV-resistant materials support long-term performance in exposed applications.
Scour protection in hydraulic engineering: frequently asked questions
Scour protection in hydraulic engineering describes the installation of armour and filter systems to prevent bed and bank material being displaced by flowing water, wave action or tidal forces. It is required wherever hydraulic structures face erosive currents: river banks, dyke toes, bridge piers, coastal revetments and offshore foundations. Without scour protection, progressive erosion can lead to undermining and structural failure.
Selection depends on exposure class, fill volume and the need for a scour flap. Secutex® Soft Rock R 801 suits standard riverine and coastal applications. Grand R 1201 and 1601 address high hydraulic loading including wave attack. Grand RS 1201 and 1601 (double-layer) are specified for extreme exposure. A Secutex® nonwoven filter layer is installed beneath the container system to prevent fine particle migration.
Scour protection design follows EAK (Empfehlungen für Küstenschutzwerke), GBB (Geotechnische Bemessung von Uferböschungen an Wasserstraßen), BS 6349 (British Standard for Maritime Structures) and PIANC guidelines. Geotextile filter layers are designed to EN 13251. Our engineering team supports specification and design for individual project requirements. Digital calculation tools are available in the Naue Portal software environment.
Containers are delivered flat-packed and filled on site using locally available sand via pre-manufactured retractable filling trunks. Containers are positioned by excavator, crane or by hand depending on geometry. Underwater installation is feasible. Secugrid® geogrid wrap can be applied around containers to secure position under strong currents and wave action.
Yes. Secutex® Soft Rock products are designed for hydraulic engineering. Geotextile filter layers comply with EN 13251. Hydraulic design follows EAK, GBB and PIANC. Engineering team provides project-specific compliance documentation on request.
Secutex® Soft Rock GSC are deployed in hydraulic projects worldwide. In Scharbeutz, Germany, containers were installed in five layers at a coastal flood protection wall to absorb wave energy and prevent retrogressive erosion. Further reference case studies are available on this page.
The Secutex® Soft Rock Grand RS 1201/1601 is specified for extreme hydraulic exposure: offshore platforms, port structures and very high wave energy environments. The double-layer nonwoven/woven composite fabric provides maximum abrasion resistance not achievable with single-layer variants. The integrated scour flap (SF) automatically covers scour ridges that form under sustained hydraulic loading, eliminating the need for manual intervention after storm events.
Secutex® Soft Rock containers can be placed underwater using crane or barge without dewatering the work area. The filter geotextile beneath the container system must be placed prior to armour installation; sand mat variants of Secutex® nonwoven are available for underwater laying. Divers or ROVs may be used to verify placement at depth. Please contact us for installation manuals.