State Transportation Innovation Council (STIC) What are the Benefits? Geosynthetic Reinforced Soil Integrated Bridge System (GRS-IBS) Geosnythetic Reinforced Soil or GRS is a very old concept that is being modernized with today’s technology. Today, GRS uses alternating layers of geotextile and compacted stone to create bridge substructure units. Those units can be combined with beams and a deck to create an Integrated Bridge System (IBS). The concept of reinforced soil has been used throughout history, including sections of the Great Wall of China that are still visible today, which affirms the durability of the GRS concept in the right application. GRS-IBS is a form of accelerated bridge construction that lowers costs and reduces construction time, minimizing the impact to the traveling public. Using the reinforced soil method for the foundation of the bridge allows the bridge to be built much faster and in an environmentally friendly manner. The GRS-IBS bridge can be built by local labor or maintenance friendly forces with readily available materials. This design concept uses less heavy equipment and does not require intricate construction concepts. Overall, GRS-IBS can reduce costs by 25-60 percent compared to conventional construction methods. GRS-IBS uses common equipment and materials and requires fewer parts which lend itself to easier maintenance. In addition, GRS-IBS also utilizes a flexible design that can be easily modified to adjust to unforeseen circumstances or weather events. GRS-IBS is a great solution to address either structurally deficient bridges on low volume roadways or over low velocity streams. In addition, studies have found GRS-IBS able to withstand scour testing up to 15 feet per second. PennDOT encourages the use of GRS-IBS technology through its inclusion in Publication 447, New Products for Low Volume Roads. This publication provides approval to local governments to utilize innovative products for their local roadways. PUB 752 GRS (8-13) Reduced construction time and costs, with costs reduced 25 to 60 percent from conventional construction methods Easy to build with common equipment and materials; easy to maintain because of fewer parts Flexible design that is easily modified in the field for unforeseen site conditions