Design of rataining walls by the felp of the computer program

60 SUMMARY When a reinforced concrete retaining wall designed sliding criterion, overturning criterion, ground pressure and concrete pressure must be between safety limits, it must also be safe against overall stability. The first step of the procedure is to give dimensions to the wall design In doing so one should rely on experience or prerequisite criterions Than the chosen dimensions are checked for the following safety criterions: Sliding criterion, overturning criterion.ground pressure criterion, overall stability criterion and concrete pressure criterion. For the safety of retaining walls against sliding, the sum of the forces which prevent sliding must be greater than the sum of the forces which tend to slide the wall. Similarly for the safety of the wall to overturning, the sum of the moments which tend to prevent overturning must be greater than the sum of the overturning moments about the heel.For ground pressure criterion, the pressures under the bottom of the wall must be.«mailer than earth safety pressure and also must be greater than zero. For overall slope stability criterion the radius of critical slip circle must be smaller than the radius of the circle which is passing through the heel point.In reinforced concrete retaining walls the compression, tension and shear stresses must be within the safe stresses for concrete and r;tee!. Generally in the design of retaining walls the effects of earthquakes are neglected for the sake of simplification.However, regarding the large size of the retaining walls as civil engineering structures and the present use of computer programs, it seems appropriate and necessary to consider the earthquake forces in their design. In the design of retaining walls the main purpose is to obtain the most economical solution which at the same time satisfies the safety criterions.From the view point of excavation, filling and wall materials the most economical solution can be obtained by comparing the results of different computations.61 The manual design procudere of reinforced concrete retaining walls may not be very difficult but the repetition of the procedure with different dimensions may be difficult and time consuming.Therefore, the most economical manual design of retaining walls depends on ability and experience.Using the present computer program the design of cantelever reinforced concrete retaining walls can be carried out by including the earthquake action.Computational procedure is initiated with some some chosen dimensions and the final configuration is reached until all the controlling criteria are satisfied.