Geogrid-reinforced bridge abutments use the RSS method (reinforced soil structure) to build the abutment as a ductile reinforced-soil body instead of a massive reinforced-concrete structure. Stiff Secugrid® geogrids and the surrounding fill form a composite “geogrid-soil” body that absorbs earth pressure behind the load-bearing components and distributes loads over a larger area. The resulting high ductility minimises differential settlement between the embankment fill and the abutment - avoiding the bump effect and joint damage typical of rigid concrete abutments - while reducing construction time and costs.
Naue RSS solutions are applied wherever a ductile, economical and low-settlement abutment is needed in place of a massive reinforced-concrete structure.
Ductile RSS abutments that remove the bump effect at the transition.
Reinforced-soil abutments that can be quickly dismantled and the materials reused.
Variable facing systems integrate the abutment into the surrounding landscape.
A rigid concrete abutment and the adjoining, settlement-prone embankment behave very differently, and the stiffness jump at their interface causes differential settlement - felt as the “bump” at the bridge and seen as damage to expansion-joint structures. A RSS abutment is itself a ductile reinforced-soil body, so its stiffness is far closer to that of the embankment. Loads are distributed over a larger area through the geogrid-soil composite, equalising deformation across the transition and removing the bump effect.
Key principle: The Secugrid® soil composite forms a ductile, earth-pressure-absorbing body - slimming the concrete structure and equalising stiffness with the embankment to remove the bump effect.
The design of geogrid-reinforced bridge abutments follows recognised standards, in Germany principally EBGEO. Naue provides engineering support and project-specific design assistance through its Engineering and Design Department (EDD).
The following system benefits come directly from how the Naue products work within the layer structure:
A RSS abutment is reinforced with Secugrid® geogrid; the project-specific choices are the facing (outer-skin) system and the fill material. The guide below outlines the common options and provides general guidance.
| Design criterion | Wrapped-around / vegetated facing | Structural facing (blocks/panels/steel mesh) | Temporary abutment |
|---|---|---|---|
| Typical use | Landscape integration; natural, vegetated faces | Architectural or urban faces; steep or vertical | Staged works or short-term bridges; later removed |
| Facing / outer skin | Geogrid wrapped at the face, vegetated | Modular blocks, precast panels or welded steel mesh | Simple wrap or reusable facing |
| Fill material | Local soils or recycled building materials | Local soils or recycled building materials | Reusable granular fill |
| Reinforcement | Secugrid® (e.g. 120/40 R6), per RSS design | Secugrid®, per RSS design | Secugrid®, per RSS design |
| Design / standard | EBGEO; project-specific design by Naue EDD | EBGEO; project-specific design by Naue EDD | EBGEO; project-specific design by Naue EDD |
In a RSS abutment, stiff Secugrid® geogrids and the compacted fill act together as a composite “geogrid-soil” body. Placed behind the load-bearing components, this body absorbs earth pressure and distributes the applied loads over a larger area, so massive concrete elements can be made significantly slimmer. The high ductility equalises stiffness between the abutment and the adjoining embankment, which is what minimises differential settlement. With suitable facing (outer skin) systems the structure stays robust under impact loads and in the event of fire, and it can be easily repaired if damaged.
Key characteristics:
Normative design confidence - RSS abutment designed to EBGEO
The RSS abutment is designed in accordance with EBGEO. The Secugrid® soil composite absorbs earth pressure behind the load-bearing components, with project-specific verification by the Naue Engineering & Design Department (EDD).
Lower cost and shorter construction programme
Using a ductile reinforced-soil body lets massive concrete elements be built significantly slimmer, reducing construction cost, construction time and disruption to traffic.
A geogrid-reinforced bridge abutment is built with the RSS method (reinforced soil structure): layers of Secugrid® geogrid and compacted fill form a composite reinforced-soil body that is placed behind the load-bearing components as an earth-pressure absorber. Because this body is ductile and distributes loads over a larger area, it behaves more like the adjoining embankment, minimising differential settlement and eliminating the bump effect - while allowing the concrete structure to be slimmer.
RSS abutments use stiff Secugrid® geogrids; the Prüm Bridge in Minden, for example, was built with Secugrid® 120/40 R6 (SP and ST). Secugrid®’s high stiffness at low strain is what gives the reinforced-soil body its ductility and load distribution. The exact type and strength are confirmed by the project-specific RSS design.
In Germany, EBGEO (Recommendations for Design and Analysis of Earth Structures using Geosynthetic Reinforcements) governs geosynthetic-reinforced soil structures, including RSS abutments. Geogrid properties are tested to EN ISO 10319 and EN 13251. All designs require geotechnical site-investigation data and project-specific verification by a qualified designer.
Using a RSS (reinforced soil structure) as an earth-pressure absorber lets the massive concrete elements be built significantly slimmer and more cheaply, with a shorter construction programme and less disruption to traffic. Locally available soils or recycled building materials can be used as fill.
A RSS abutment is built up in compacted layers: fill is placed and compacted, a Secugrid® geogrid layer is laid and connected to the chosen facing (outer-skin) system, and the sequence is repeated to the design height. The facing can be a wrapped-around (vegetated) face or a structural face such as modular blocks, panels or steel mesh. Construction uses standard earthworks plant; no specialist equipment is required.
With suitable facing systems, the ductile RSS body remains robust even under impact loads or in the event of fire, and it can be easily repaired if damaged. This robustness is why, in Japan, KBE construction has been established as a standard method for high-speed railway lines, owing to its performance during earthquakes. Geogrid design strengths account for installation damage, creep and environmental factors to EBGEO; data is available upon request.
Yes. Because the abutment is a reinforced-soil body rather than a monolithic concrete structure, temporary RSS abutments can be quickly and easily dismantled at the end of their service, and the fill and components can be reused. This makes RSS well suited to temporary bridges and staged construction.
The facing (outer-skin) system of a RSS abutment can be varied to suit the project. A wrapped-around, vegetated face integrates the structure into a natural landscape, while structural faces such as modular blocks or panels suit urban or architectural settings. This adaptability is one of the practical advantages of RSS construction over a fixed concrete form.
Yes. RSS abutments are used for both road and railway bridges. The high ductility is particularly valuable for railways: in Japan, RSS construction is a standard method for high-speed lines because of its robustness during earthquakes. For rail, the stringent settlement limits and dynamic loading require careful project-specific RSS design to EBGEO or the relevant national railway standard.
Naue Combigrid® is a geogrid with integrated nonwoven geotextile that combines stabilisation, reinforcement, separation and filtration in a single installation step.
