Reinforce retaining walls: geogrid for MSE walls and steep slopes
Reinforced earth retaining walls and mechanically stabilised earth (MSE) structures are engineered solutions for building stable, near-vertical embankments or embankments with steep slopes without concrete. Conventional concrete retaining walls are costly and structurally rigid. Secugrid® uniaxial geogrids and Combigrid® composite products replace concrete with reinforced compacted soil, delivering equivalent load capacity at significantly lower cost.
Retaining walls and MSE structures with geogrids | Naue | Naue
At a glance
Application: Construction of near-vertical embankments or embankments with steep slopes, MSE walls and reinforced slopes using compacted soil reinforced with geogrids, without concrete.
Products: The primary Naue products are Secugrid®, Combigrid®, Secutex®.
Savings potential: Cost advantage compared with concrete gravity walls.
Standards: Design follows EBGEO, BS 8006-1, FHWA-NHI, AS 4678, EN ISO 10319.
Retaining walls: challenges, solutions and measurable results
Challenges
Limited space for conventional gravity walls
High lateral earth pressure on steep slopes
Settlement risk at bridge abutments and embankment edges
High cost of concrete walls
Differential settlement at structure transitions
Solution
Secugrid® uniaxial geogrid for MSE wall construction
Secugrid® for reinforced slope and steep embankment design
Combigrid® for combined reinforcement and separation in one layer
Secutex® nonwoven geotextile for drainage and filtration in wall backfill
Multi-layer geogrid systems for very high walls or heavy surcharges
Result
Up to 40 % cost reduction compared with concrete gravity walls
Geogrid veneer walls can save up to 403 USD/m2 compared with gravity walls (GRI Conf., Dr. Koerner, Drexel University)
Near-vertical walls at inclinations of 85 degrees or steeper are feasible with wrap-around method
Shorter construction time through simplified earthwork and the elimination of formwork curing
Typical applications for retaining walls and reinforced earth structures
Secugrid® and Combigrid® reinforced earth solutions are deployed wherever stable structures are required on a limited footprint, in steep terrain or at sensitive locations.
MSE walls
Near-vertical mechanically stabilised earth walls for road widening, bridge approaches and urban development.
Bridge abutments
Geogrid-reinforced bridge approach embankments that reduce differential settlement and approach slab cracking.
Mining embankments
Reinforced waste rock embankments and tailings containment structures for mining environments.
Green facades
Vegetated reinforced slopes and green retaining walls for urban landscaping and ecological restoration.
Project design for retaining walls and reinforced earth structures
MSE wall and reinforced slope design is carried out in accordance with recognised standards. Naue provides engineering support and calculation tools for project-specific dimensioning.
EBGEO (Germany): MSE walls, reinforced slopes and embankments - design of LTDS and internal stability
BS 8006-1 (UK): Reinforced soil walls and slopes - full limit state design approach
FHWA-NHI (USA): MSE wall design for highway and bridge abutment applications
AS 4678 (Australia): Earth-retaining structures including reinforced soil walls
EN ISO 10319: Tensile testing of geogrids - basis for LTDS calculation
Secugrid® in MSE walls: robust under load and during installation
Mechanically stabilised earth (MSE) walls are built by placing compacted fill in lifts, each reinforced with a geogrid layer. The geogrid must resist installation damage during compaction while delivering high tensile stiffness at low elongations. Secugrid® uniaxial geogrids are manufactured from highly oriented polyester bars joined by Naue’s patented welding, producing a geogrid with high modulus and proven installation damage resistance.
Practical advantages:
High tensile stiffness at less than 2 % elongation - Secugrid® picks up load with minimal wall deformation
Installation damage reduction factor (RFid) determined in project-specific field tests in accordance with EBGEO - RFid of 1.1 verified for Secugrid® 120/40 R6 (Saxon Textile Research Institute, stfi)
Wrap-around facing method: walls of up to 40 individual geogrid layers can be built at 85 degrees, combining Secugrid® 80/20 R6 and Secugrid® 200/40 R6 for variable force zones
Combigrid® provides reinforcement and drainage in a single layer, reducing component interfaces on site
Drainage and filtration behind retaining walls: when do you need both?
Long-term wall stability depends on controlled drainage of the reinforced fill. Excess pore-water pressure in wall backfill reduces soil strength and increases lateral earth pressure. A drainage and filtration system prevents fine particles from migrating into the drainage layer and maintains wall integrity.
Reinforcement improves load capacity. Drainage and filtration protect the structure long-term.
Geogrid and drainage/filter geotextile
Secugrid® R for structural reinforcement
Secutex® nonwoven geotextile as a drainage and filter layer to prevent fine migration
Two components - flexibly combined according to project requirements
Technical benefit: Components can be independently specified and replaced.
Composite product (one layer instead of two)
Combigrid® is a factory-bonded composite of Secugrid® and Secutex®
Advantage on site: one layer, fewer interfaces, faster installation
Preferred when both reinforcement and drainage-filtration are required simultaneously
Technical benefit: Single-layer installation eliminates the risk of component misalignment.
Secugrid® or Combigrid® for retaining walls? A structured decision guide
The right product depends on project conditions. This table provides engineers and specifiers with a structured comparison across seven key criteria.
Criterion
Secugrid®
Combigrid®
Application
MSE walls, reinforced slopes, steep embankments.
MSE walls and reinforced slopes where reinforcement and separation/filtration are required in the same layer.
Subgrade / fill type
Granular or cohesive fill; any compactable material.
Fine-grained or water-sensitive subgrades and fills where migration of fines must be prevented.
Load class (structural)
High — primary reinforcement; uniaxial strength in the machine direction.
Reinforcement plus separation; grid component selected to suit the design load.
Installation speed
Two placement operations — geogrid plus a separate drainage geotextile where required.
Single layer — one roll, fewer interfaces, no risk of component misalignment.
Drainage / filtration
Requires a separate Secutex® layer or a drainage composite.
Integrated: Secutex® nonwoven factory-bonded to the geogrid.
Standards
EBGEO, BS 8006-1, FHWA-NHI, AS 4678, EN ISO 10319.
EBGEO, BS 8006-1, FHWA-NHI, AS 4678, EN ISO 10319.
Criterion
Secugrid®
Combigrid®
Recommended product
Secugrid® 80/20 R6, 120/40 R6, 200/40 R6.
Combigrid® (grid/nonwoven combination per project)
Retaining walls and reinforced earth structures: your benefits
Design confidence and normative compliance
MSE walls are designed in accordance with EBGEO, BS 8006-1 and FHWA-NHI standards. Long-term design strength (LTDS) calculated with project-specific reduction factors for installation damage, creep and durability. Secugrid® is certified up to pH 12.5, covering highly alkaline environments.
Cost efficiency up to 40 % compared with concrete
Geogrid-reinforced walls can cost up to 40 % less than concrete gravity walls. Veneer wall systems can save up to 403 USD/m2 compared with gravity wall alternatives (GRI Conference 2000).
Simple installation - no specialist equipment
Secugrid® is installed in 60 cm compacted lifts. No specialist equipment required. Combigrid® delivers reinforcement and drainage in one roll, reducing material handling and coordination on site. The wrap-around method provides a permanent facing without steel or concrete formwork.
Retaining walls and reinforced earth structures: frequently asked questions
A reinforced earth retaining wall is a structure built from layers of compacted fill reinforced with horizontal geogrid elements. The composite of soil and geogrid acts as a coherent mass resisting lateral earth pressure. Secugrid® uniaxial geogrids are the primary reinforcement element. No concrete is required.
Use Secugrid® where only structural reinforcement is required and drainage is addressed separately. Choose Combigrid® where both reinforcement and filtration are needed in one layer. Combigrid® simplifies site logistics and reduces material interfaces in wall backfill zones.
Design is carried out in accordance with EBGEO in Germany, BS 8006-1 in the United Kingdom, FHWA-NHI in the United States and AS 4678 in Australia. Long-term design strength (LTDS) is calculated in accordance with EN ISO 10319 using project-specific reduction factors for installation damage, creep and chemical durability.
Geogrid-reinforced veneer walls can save up to 403 USD/m2 compared with gravity walls (GRI Conference 2000, Dr. R. Koerner, Drexel University). Overall wall construction costs cn be up to 40 % lower than equivalent concrete gravity structures.
Fill is placed and compacted in 60 cm lifts. Secugrid® geogrid is rolled out horizontally at each lift boundary and anchored by the compacted fill. For wall facing, the wrap-around method is used with galvanised steel grid formwork as permanent facing. No concrete pour or curing time is required.
Yes. Secugrid® geogrids hold European Technical Approvals and national certifications. Alkaline resistance is certified up to pH 12.5. The installation damage reduction factor is determined by field testing to EBGEO. Projects in the UK follow BS 8006-1; in the US, FHWA-NHI design guidance applies.
MSE walls with Secugrid® have been constructed at heights exceeding 20 m. A 40-layer wrap-around wall was built in Marbella, Spain at an inclination of 85 degrees using Secugrid® 80/20 R6 and 200/40 R6 in combination. Also see more case studies here.
Long-term design strength (LTDS) is the design tensile resistance of a geogrid after accounting for all degradation mechanisms over the design life, typically more than 100 years. For Secugrid®, LTDS is derived from characteristic tensile strength (EN ISO 10319) divided by reduction factors for installation damage (RFid), creep (RFcr) and chemical durability (RFch) in accordance with EBGEO or BS 8006-1. Project-specific field tests determine RFid values.
Yes. The wrap-around facing method with Secugrid® allows topsoil pockets to be formed at the slope face, enabling grass or shrub planting. Secumat® erosion control mat can be applied to the face to retain topsoil and support rapid vegetation establishment. Naue Steel P combines galvanised steel mesh facing with a vegetation layer for permanent structures at inclinations up to 85 degrees.
®
®
Vegetated facing option for ecological integration