First Geofoam Roadway Embankment Application in Turkey

The first geofoam block roadway embankment application in Turkey was completed in April 2017 in Acibadem, Istanbul. Geofoam technology was selected to construct the roadway embankment on a site where two 2.2 m diameter water mains are located 3.8–5.6 m below the foundation of the embankment. Geofoam blocks not only prevented the relocation cost of this infrastructure in a very complex urban setting in terms of buried utility corridors, but also prevented possible structural damage to the mains if conventional earth fill was used to construct the embankment. In addition, water service was not interrupted during the construction. The project background, design considerations, and construction sequence is presented. In order to monitor the performance of the embankment, a field instrumentation array comprised of extensometers was installed in the foundation soil, bedding sand, geofoam block assemblage, and under the load distribution slab. Instrumentation details and monitoring results over a period of ten months is discussed, and long-term performance projections were evaluated using short-term performance data.