Investigation and Mitigation of Failure of Reinforced Earth Retaining Wall

In the country, numerous significant road infrastructure developments are going on under different national programs such as Bharat Mala, Sagar Mala, Char Dham, and Ganga Expressway by the National Highway Authority of India (NHAI) and National Expressway Authority of India (NEAI). Due to this, thousands of bridges, flyovers, and vehicular underpasses are being constructed to smoothen and ease the traffic flow. Accordingly, approaches to these structures are being constructed by reinforced earth retaining walls. However, in recent years, the failure of several RE walls has been reported and studied in the literature. Each RE wall has a typical reason for failure and mitigation method. Considering this, a detailed literature review was carried out regarding the failure of RE walls nationally and globally. Systematic failure analysis and investigation were carried out to explore the causes of failure of such RE walls. Different types of failures were observed due to poor construction methodology and inferior quality of materials. Some of the reasons for the failures are settlement of the foundation, bulging of the facia panel, cracking of the facia panel, quality of filter material (aggregate/geocomposite), quality of reinforced and retained fills, poor drainage arrangement, quality of reinforcements, design failure, etc. In this chapter, different investigation methodologies have been discussed regarding the failure of the RE wall to explore the causes of failure. Details of causes of failure have been presented along with mitigation methodology. Statistical analysis was carried out to illustrate the quantification of failure of the RE wall with respect to the causes of failure. It was observed that poor construction practice is the primary effective reason (46%) of failure, while poor maintenance is the least effective parameter for the failure of the RE wall (5%). This chapter will help the highway engineers reduce/minimize the failure of the RE walls.