
Naue SoftRock
Geotextile sand container design for coastal and hydraulic works
Naue SoftRock is a free online calculator in the Naue Portal DesignSuite for the design and quantity estimation of Secutex® Soft Rock® geotextile sand containers - a flexible, sand-filled alternative to rock armour for coastal and hydraulic engineering. It sizes the containers and estimates the quantity needed for scour protection, coastal protection, revetments and breakwaters, using recognised design models (Bouyze & Schram 1990, Recio & Oumeraci 2007) and considering wave, current or combined hydraulic loading. Engineers enter the structure, water levels and hydraulic conditions and receive the required Soft Rock container and quantity for a stable, durable solution.
At a glance
- What it is: a free online calculator in the Naue Portal DesignSuite (login required)
- What it does: designs and estimates the quantity of Secutex® Soft Rock geotextile sand containers under wave and current loading
- Applications: scour protection, coastal protection, revetments and breakwaters
- Design models: Bouyze & Schram (1990); Recio & Oumeraci (2007)
- Key inputs: application and design model; structure (shape, diameter, single or group); water levels (MHW, SWL, MLW); loading condition (waves, current or combined); wave conditions (significant wave height, peak period, water density) and current velocity
- Key outputs: required Secutex® Soft Rock container size/variant (e.g. R 601, RS 801a, RS 1201, Grand R/RS) and quantity (total covered length), sand fill volume (approx. 1 m³ per container) and filter layer for the given hydraulic loading; downloadable report
From hydraulic loading to a sized solution: how SoftRock delivers
Challenges
- Protecting structures and shorelines against wave, current and scour
- Rock armour can be costly, heavy and hard to place accurately
- Sizing sand containers and quantities to recognised methods
Naue solution
- A calculator that sizes Secutex® Soft Rock geotextile sand containers to established design models for the actual wave and current loading
Results
- The required Soft Rock container and quantity for your structure
- A stable, flexible, sand-filled solution for scour, coast and breakwaters
- A documented design and quantity estimate, with a downloadable report
Where SoftRock helps: applications covered
Naue SoftRock is used wherever structures and shorelines need protection against hydraulic attack - and where flexible, sand-filled geotextile containers offer a durable, cost-effective alternative to rock.
- Scour protection: protection around piers, foundations and structures against scour
- Coastal protection: shoreline and dune protection against wave attack
- Revetments: slope and bank revetments for coasts and waterways
- Breakwaters: flexible sand-container breakwater and mole construction
- River & bank works: bank and bed protection under current and wave action
How SoftRock works: application, loading and quantity
A short, guided flow captures the application, the structure and the hydraulic loading, then sizes the Secutex® Soft Rock containers and estimates the quantity - with the option to save the calculation to a project.

Start from your use case and the design basis:
- Application: scour protection, coastal protection, revetment or breakwater
- Design model: Bouyze & Schram (1990) or Recio & Oumeraci (2007)
- Guided, parameter-driven workflow - no manual stability formulas

Describe the structure and the hydraulic environment:
- Structure: shape (e.g. circular), diameter, and single or group arrangement
- Water levels: mean high water (MHW), still water level (SWL) and mean low water (MLW)
- Loading condition: waves, current, or combined waves and current
- Wave and current data: significant wave height, peak period, water density and current velocity

SoftRock turns the inputs into a sized, documented solution:
- The required Secutex® Soft Rock container size/type for the hydraulic loading - matched to a specific product variant (e.g. R 601, RS 801a, RS 1201 or Grand R/RS) and, where relevant, a Secutex® filtration nonwoven
- The estimated quantity and total covered length of Soft Rock for the structure, plus the required sand fill volume (approx. 1 m³ per container) and any filter layer / overlap shown in the cross-section
- A downloadable report; save the calculation to a project in the Naue Portal
- Direct links to the Naue Engineering & Design Department (EDD) for non-standard structure shapes or complex projects

For coastal & hydraulic engineers: stability design of geotextile sand containers to recognised models for waves, current or combined loading - a defensible sizing and quantity basis. The Naue EDD supports non-standard cases.
For contractors and site managers: clear container sizes and quantities for procurement and placement, with a flexible, sand-filled system that is quick to install where rock is impractical.
For project owners and clients: a durable, cost-effective and environmentally friendly protection solution, with a documented design and quantity estimate for budgeting and approval.
SoftRock: method, standards and engineering support
| Method / Basis | Scope |
|---|---|
| Bouyze & Schram (1990) | Stability design model for geotextile sand containers |
| Recio & Oumeraci (2007) | Stability design model incorporating wave and current effects |
| Hydraulic loading (waves / current / combined) | Wave height and period, current velocity and water levels drive the design |
| Secutex® Soft Rock® containers | Flexible, sand-filled geotextile armour units sized by the tool |
| Naue EDD | Project-specific review and design support, including special structure shapes |
| SoftRock applies recognised stability design models for geotextile sand containers, combined with the performance of Secutex® Soft Rock® products. Where a project needs individual review - for example a non-standard structure shape - the Naue Engineering and Design Department (EDD) supports designers and contractors with project-specific design. |
The SoftRock advantage: flexible, durable, right-sized protection
Naue SoftRock makes it fast and reliable to design flexible, sand-filled protection for coasts, waterways and marine structures. By sizing Secutex® Soft Rock containers to recognised models for the real wave and current loading, it delivers a stable, durable and cost-effective alternative to rock armour - with clear quantities for procurement and a documented report for approval, backed by Naue's engineering support.
Naue SoftRock: frequently asked questions
Naue SoftRock is a free online calculator in the Naue Portal DesignSuite that designs and estimates the quantity of Secutex® Soft Rock geotextile sand containers for coastal and hydraulic engineering, under wave, current or combined loading.
They are sand-filled geotextile containers used as a flexible, durable alternative to rock armour. They conform to the seabed or slope, are quick to place, and suit scour, coastal, revetment and breakwater applications.
Scour protection, coastal protection, revetments and breakwaters - the main uses of geotextile sand containers in marine and hydraulic works.
It offers recognised stability design models for geotextile sand containers: Bouyze & Schram (1990) and Recio & Oumeraci (2007).
Waves only, current only, or combined waves and current - so the design reflects the real hydraulic attack at the site.
The application and design model, the structure (shape, diameter and single/group arrangement), the water levels (MHW, SWL, MLW), the loading condition, and the wave and current data (significant wave height, peak period, water density and current velocity).
You receive the required Soft Rock container size and variant, the estimated quantity and covered length and the sand fill volume, with a downloadable report, and you can save the calculation to a project in the Naue Portal.
SoftRock is free within the Naue Portal and requires a portal login. It is aimed at coastal and hydraulic engineers, contractors and project owners; for non-standard structures the Naue EDD can assist.