REINFORCED EARTH A MAJOR INNOVATION. The Reinforced Earth Group has developed several techniques that have advantages in common:

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2 CONTENTS INTRODUCTION > 03 TECHNOLOGIES > 04 ROADWAY APPLICATIONS > 06 RAILWAY APPLICATIONS > 08 INDUSTRIAL AND PROTECTIVE APPLICATIONS > 09 HYDRAULIC APPLICATIONS > 10

3 REINFORCED EARTH A MAJOR INNOVATION Reinforced Earth is recognised as a major innovation in the field of civil engineering. Owners, engineers and contractors, worldwide, make use of it for the construction of many types of structures, predominantly retaining walls and bridge abutments. The merging of the Reinforced Earth and Freyssinet Groups in 1998 further widens the range of materials and applications and confirms the group as the world leader of soil reinforcement, both metallic and synthetic. The group is present on all five continents, and benefits from both local experience and worldwide expertise. The Reinforced Earth Group has developed several techniques that have advantages in common: Long service life due to use of reliable and durable materials; Considerable savings in both construction time and material costs; Aesthetically pleasing structures that blend with the environment. The Reinforced Earth technique has revolutionized construction, and can be applied to all types of retaining structures, including: Roadway structures; Railway structures; Industrial and protective structures; Marine and river structures.

4 TECHNOLOGY SOIL REINFORCEMENT Soil reinforcement is the main field of activity of the Reinforced Earth Companies, combining both the geotechnical and structural engineering disciplines. The technology is based on the formation of a composite material through the association of compacted frictional fill and linear soil reinforcement. The soil reinforcement may be either metallic (like the high adherence galvanised steel strips) or synthetic (like the polyester-based Freyssisol strips). Reinforced Earth provides: STRENGTH The resistance and stability of the composite structure provides significant load-bearing capacity. COST EFFECTIVENESS The ease and speed of construction are significant advantages in reducing overall cost. RELIABILITY The durability of the materials used is well documented and the safety of the structures unrivalled. ADAPTABILITY The technology provides solutions to complex cases and often proves to be the best answer to circumstances such as restricted right-of-way, unstable natural slopes, marginal foundation conditions and large settlements. AESTHETIC APPEARANCE The variety of facings can meet all architectural requirements. 1. TerraTrel wall in Annecy, 2. Installation of precast facing units. 3. Backfilling over synthetic Freyssisol strips. 4. Installation of galvanised steel strips. 5. Backfilling over galvanised steel strips. 04

5 TECHNOLOGY PRECAST ARCH Lengthening of existing tunnels in Orte-a-Fiano, Italy. 7. Prefabrication of TechSpan arch units, Spain. 8. TechSpan arch under high-speed train line, Torremocha, Spain. 9. Construction of CTRL (Channel Tunnel Rail Link), United Kingdom. 10. Installation of TechSpan arch over Homebush Bay railroad, Australia. Invented and developed by the Group, the TechSpan arch system also involves the interaction between the structure and the surrounding fill. TechSpan is used for the construction of cut-and-cover buried tunnels, for roadway, railway, industrial, protective and hydraulic applications. The TechSpan system is based on assembling short half sections of arch. The prefabricated reinforced concrete units are set on strip footings at the toe of structure, and lean against each other at the crown. A half-length offset of units allows rapid construction with one crane. The curvature of the arch is optimised for every project based on site constraints, application, and design requirements. Structures with spans exceeding 20 meters or with heights of surcharge backfill in excess of 30 metres have been successfully constructed and put in service. For soil reinforcement, as well as for prefabricated arches, the Reinforced Earth Companies are involved in all stages of each project, including: Feasibility; Design; Supply of prefabricated units, reinforcement, and accessories; On site technical assistance during installation. All supplied materials are manufactured in plants either operated by, or carefully selected by the local Reinforced Earth Company. The Reinforced Earth Company in your region may offer other prefabricated products and construction systems

6 ROADWAY APPLICATIONS The Reinforced Earth technique is widely used in highway and municipal projects. Most applications are for the construction of retaining walls and bridge abutments that support roadways in both urban and suburban environments, and in rural mountainous terrain. The completion of Reinforced Earth projects requires only a short construction time and minimum right-of-way, so the disruption to traffic is considerably reduced. The versatility of the technology allows for a wide variety of geometry. Prefabricated units in various attractive finishes can be used for the facing. The main uses of the technology include: Walls to support roadways, either single, or tiered; Bridge abutments; Curtain walls around pile supported abutments; Walls for access ramps; Reinforced slopes. 1. Supporting bridge abutments above railroads, A87-A71, Vierzon, 2. Walls supporting East ring-road, Limoges, 3. Supporting bridge abutments, Pozo Cañada, Spain. 4. Ramp walls in Kuala Lumpur, Malaysia. 5. TechSpan arch under high-speed train line, Torremacha, Spain. 06

7 Retaining wall in Raon l Etape, 7. Twin arch, Spain. 8. A75, Pégairolles de l Escalette, 9. A29, Rogerville valley, TechSpan arches are used for: Road underpasses or overpasses; Cut-and-cover tunnels; River crossings. Such structures are often completed with Reinforced Earth head-walls and wing-walls.

8 RAILWAY APPLICATIONS Reinforced Earth retaining walls are used in many countries along railway, metro and light rail transit lines. The technology is the same as for roadway applications, except for a few specific details. The design of the retaining structures is adapted to comply with the stringent requirements related to heavy loads and safety, especially for highspeed railways. Reinforced Earth structures absorb the vibrations induced by passing trains, inherently well. structural footing in front of the cladding. As a result, the wall can be built without interruption of traffic. TechSpan arches are frequently used as well for the construction of railroad tunnels beneath earthen embankments. They can be constructed over existing railway tracks without closing the line. 1. Homebush Bay tunnel, Australia. 2. Shenton Avenue tunnel, Australia. 3. Railway retaining wall, Lisbon, Portugal. 4. Light rail transit system, Portland, Oregon USA. 5. Railway relocation, Ralston Holly, USA. Building a Reinforced Earth retaining wall along a railway does not require any scaffolding, or any 08

9 HYDRAULIC APPLICATIONS Applications along rivers, lakes and coastal areas are common for Reinforced Earth technologies. Several reasons justify the owners choice: Resistance to severe loading conditions such as flooding and drawdown, tidal fluctuations, storms, ice and other impacts; Rapid construction, especially for the works carried out in the tidal range, by virtue of simultaneous placement of fill, reinforcement and facing. Underwater construction of Reinforced Earth quay-walls is achieved with a uniquely modified system. This method was successfully used in several countries, for marinas and fishing ports. The Freyssisol strip is particularly well suited to salty and marine environments. A significant part of the TechSpan references belongs to their use in hydraulic applications. The adaptability of the arch shape allows optimisation of the section while respecting the anticipated water flow. This optimisation and the inherent savings of using prefabricated units, combined with the ability to construct without diverting the stream, makes TechSpan a solution of choice for such applications. 1. TerraClass and TerraTrel retaining walls in Den Bosch, The Netherlands. 2. Taylor Draw dam, Rangely, Colorado, USA. 3. TerraSet headwalls, Millau detour, 4. Retaining wall in Louveciennes, 5. TechSpan arch and TerraTrel sloping wall, RN 200, Pont de Valle, Corsica, 10

10 1 1. Springfield interchange, Springfield, Virginia, USA. 2. Access ramp wall, Roissy-en-Brie, 3. Bridge abutments, Western Beltway near Orlando, Florida, USA. 4. Retention dikes, Montoir de Bretagne, 5. Channel Tunnel Rail Link, United Kingdom. 2 3 Photographs: Francis Vigouroux, Claude Cieutat, Freyssinet photographs and subsidiaries trademarks. 4 July Reinforced Earth are registered trademarks of the Freyssinet Group. 5

11 09 INDUSTRIAL AND PROTECTIVE STRUCTURES 6. TerraTrel and TerraClass walls, Moranci mine, USA. 7. TerraMet wall in the Pilbara Iron Ore Region, Australia. 8. Glory hole coal handling facility, Canada. 9. Foam tanker, Muskeg, Canada. 10. Avalanche barrier, Iceland. The Reinforced Earth technology is well suited for use in industrial applications. Specific solutions have been developed for the bulk handling of coal and other minerals, as well as for dump-walls adjacent to crushers, or screening plants. Today, several hundred dump-walls are in service throughout the world, and many of them rank among the highest Reinforced Earth structures. Industrial applications have unique features, such as: Versatility of the facing technology. Concrete panels, steel sections or wire mesh can be used to conform to the required geometry (face inclination, straight or curved alignment); Resistance to vibrations (crushing and screening); Outstanding resistance to thermal variations. Reinforced Earth is also an ideal material for the construction of civil, military or industrial protective works. Many such structures have withstood impact, explosion, liquid gas and other fluid spills, and fire. TechSpan arches prove to be a reliable, speedy and economical solution for the construction of military shelters and ammunition bunkers, as well as for conveyor tunnels at industrial plants

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