For construction of approaches to flyovers and Road Over Bridge’s, Reinforced earth technology has almost completely replaced conventional retaining structures. Geogrid Reinforced earth wall retaining structures have gained wide acceptance in India as a technically proven and cost effective alternative to conventional concrete retaining wall. The ongoing and planned initiatives of central and state governments for improving the road infrastructures in the country are likely to give a major boost for the demand for Geogrid reinforced wall systems. Geosynthetics have become well established construction material for geotechnical and environmental applications in most parts of the world. Results from recent research and from monitoring of instrumented structures throughout the years have led to new design methods for different applications of geosynthetics. The geosynthetic reinforced soil has emerged in the last few decades as a technically attractive and cost effective solution to many geotechnical problems. This concept was used for the construction of vertical wall in the Outer Ring Road of Hyderabad
So a research work was carried out to study about the material required for the construction of reinforced earth wall and its specifications and also the construction methodology adopted. A cost and time comparison study was also carried out between reinforced earthen wall and conventional retaining wall, and it was found that the cost for the construction of reinforced earthen walls was approximately 20% less than the cost of conventional retaining wall. From the time comparison study it was observed that the time required for construction of reinforced earthen walls was more when compared to the construction of retaining walls. But if the wall height is more the reinforced earth walls can be preferred in the context of their stability, and also in its capacity to reduce the future settlement of pavement by controlling the erosion of soil fill with the help of geotextile placed between the soil fill and drainage aggregate.
Introduction
A retaining structure is used for maintaining the ground surface at different elevations on either side of it. Geo grid reinforced earth technology has almost completely replaced conventional retaining structures with the help of geosynthetics. Over the years, these products have helped designers and contractors to solve several types of engineering problems where the use of conventional construction materials would be restricted or considerably more expensive. There are a significant number of geosynthetic types and geosynthetic applications in geotechnical and environmental engineering. Common types of geosynthetics used for soil reinforcement include geotextiles (particularly woven geotextiles), geogrids and geocells. The combination of improved materials and design methods has made possible engineers to face challenges and to build structures under conditions that would be unthinkable in the past
The foundation on which the gabions are to be placed shall be cut or filled and graded to the lines and grades shown on the drawings. Surface irregularities, loose material, vegetation, and all foreign matter shall be removed from foundation surface area. When fill is required, it shall consist of materials conforming to the specified requirements. Gabions and bedding or specified geotextiles shall not be placed until the foundation preparation is completed, and the subgrade surfaces have been inspected and approved by the engineer or the engineer’s representative. Compaction of bedding or filter material will be required per plans and specifications. The surface of the finished material shall be to grade and free of mounds, dips or windrows. Extra care should be taken with foundation preparations in order to ensure a level and smooth surface. Geotextile shall be installed in accordance with the requirements of the plans and specifications.
U N D E R C O N S T R U C T I O N