EARTH PRESSURE BEHIND RETAINING WALL WITH REINFORCED BACKFILL

Abstract

Reinforced soil is a composite engineering material consisting of compacted soil, horizontal layers of reinforce-ment and a form of facing to prevent erosion of soil. The increased use of this material is primarily due to its versati-lity , cost effectiveness and ease of construction. The versati-lity of reinforced soil makes it suitable for the construction of retaining walls, walls supporting embankments, seawalls and quays, Bridge abutments, slabs and special structures. In the present study experimental investigations have been carried out on an alternative frim of soil reinforcing for retaining walls, where the lateral pressures on conventional retaining walls are sought to be reduced by reinforcing the backfill by unattached horizontal strips. Small scale model tests were performed on a rigid retaining wall (62.5 x 50 x'1.27 cm thick) for active case. The reinforcements used were strips of Khadi cloth and bamboo, cheapest and easily available in India. Backfill of cohesionless soil was provided with different surcharge intensities and the effects on lateral earth pressure by measuring the overturning force at fixed height were studied. Pull out tests on Bamboo reinforcement were also carried out to study the effect of surcharge on the coefficient of soil-reinforcement strip friction and to compare with theore-tical analysis presented by Talwar(1981). A pertinent review of the literature on the topic has been included.