ABSTRACT
This paper is aimed to study the effect of chimney drain on the performance of geogrid reinforced soil walls with marginal backfills. Three centrifuge model tests were performed using a 4.5 m radius beam centrifuge facility available at IIT Bombay at 40 g. All models were subjected to seepage simulating rising ground water condition. Marginal soil type, the wall height, reinforcement length, and spacing and facing type was kept constant. Two types of chimney drain were used in this study including chimney nonwoven geotextile drain and chimney sand drain. Pore water pressure and displacement transducers were used to monitor the wall behaviour during centrifuge tests. Moreover, image analysis technique was used to obtain the displacement field of the models. The geogrid reinforced soil wall without chimney drain experienced global stability failure soon after inducing seepage. Application of chimney geotextile layer could not improve the wall behaviour but caused a delay on the occurrence of global stability failure. On the other hand, the application of chimney sand drain improved the wall behaviour effectively.
