Abstract:
For relief shelf supported cantilever retaining wall, the relief shelves are constructed monolithically with the wall and extended within the backfill material to increase wall’s stability. Research shows that the provision of relief shelves reduces the intensity of influential parameters, such as lateral earth pressure, shear stress and wall top moment etc., on the wall which alternately increases its stability, economically. Several research studies are available in the literature, reporting the behavior of shelf supported retaining walls with levelled non-cohesive backfill. However, the research is insignificant in this context for inclined cohesive backfill. So, this study investigates a single and two shelves supported retaining wall with inclined silty clay backfill for lateral earth pressure, shear stress, wall top movement and base sliding. Several different combinations of inclined backfills are tested in the study, keeping water table at mid and top depth of the wall. A commercial software, Plaxis 2D was used to attain the set objectives. The test results show that the provision of relief shelves enables to increase the stability of cantilever retaining wall reducing its active pressure, overturning moment, shear stress and base sliding. The simple retaining wall relatively provides quite lower factors of safety than relief shelve supported retaining walls. The simple wall is even unable to provide safe factors of safety against sliding and overturning for levelled backfill, i.e., 0o backfill inclination but the relief shelves supported walls are safe up to a backfill inclinations of 20 to 25o. The test data shows that there are significant benefits to use relief shelves to strengthen the retaining wall of silty clay backfill. However, there is no efficacy to use backfill inclination beyond a certain angle as factors of safety initiate to decrease, which is associated with collapsing/destabilization of soil mass due to its higher inclination.
