Frictional behavior between geosynthetic reinforcement and facing blocks

Abstract

Geosynthetic reinforced soil retaining walls (primarily those with precast con- crete block facing elements) reinforced by geogrids or geotextiles are in a period of rapid growth. The construction of geosynthetic reinforced soil retaining walls has gained popularity throughout the world and is becoming widespread in Turkey. Geosynthetic reinforced soil retaining walls with precast concrete block facing elements provide an aesthetically pleasing, cost-effective alternative that is easy to construct. In the con- struction, geosynthetic reinforcements are placed between the precast concrete block facing elements. This study investigates the frictional behavior between geosynthetic reinforcement and facing segmental (modular) block walls. For this purpose a specially designed machine was and a reduced size loading test program has been utilized. Two different blocks were used in the tests. As reinforcement types, ve different geogrids and a woven geotextile were used. These geosynthetic types are the most common geosynthetic types used for reinforced earth wall construction. The facing blocks used were hollow concrete blocks. Test were conducted where the space inside the block was left empty or lled with gravel. Tests under various normal stresses were conducted. The pull-out force was increased until pull-out occurred. An interface friction angle was calculated in each group from the relationship between the normal load applied to geosynthetic reinforcements and pull-out load at failure point. In addition to regular pull-out tests, two-types of tests are conducted to check whether there are other vari- ables that may affect test results, namely, roughness tests and compression tests. At the end of the tests, it can be concluded that the combination of the gravel lled con- crete blocks and geogrid proved to give the best performance to be used in geosynthetic reinforced soil retaining walls in terms of connectivity strength.