DESIGN REQUIREMENTS FOR THE VARIOUS COMPONENTS OF THE RETAINING WALLS:--

The forces acting on the Retaining wall are , Earth pressure,Weight of earth supported on heel ,Weight of the stem and Weight of the base and the weight on the earth on the toe portion is neglected. The resultant of these forces should cut the base in the middle third so that no portion of base is lifted up, ie no tension is developed at the base .The maximum pressure at the base should not exceed the allowable pressure on the soil.  DESIGN OF THE TOE :-- The toe is subjected to upward pressure from the soil and self load which acts downwards. The maximum S.F and B.M will occur at the face of the stem. Adequate depth and reinforcement is provided to resist S.F and B.M . DESIGN OF HEEL:-- The heel is subjected to upward pressure from the soil and downward load due to self weight and earth above the heel .The BM and the SF will be maximum at the junction of heel with stem .The B.M due to earth retained and self load will be more than that due to upward pressure from soil . Adequate depth and reinforcement are provided to resist S.F and B.M . CHECK AGAINST THE SLIDING :-- The tendency of earth pressure is to slide the base .This effect is counterbalanced by the friction between base and the soil.In case the frictional resistance is not sufficient, key is provided preferably below the stem . APPROXIMATE FORMULA FOR THE BASE WIDTH :--Generally base width of the Retaining wall lies between 0.5H to O.6 H where H is the height of the retaining wall.