Civil Engineering - RCC Structures Design - Discussion

Used for 3 to 8m height.

Only Cantilever wall height should be 6 metre.

Generally, economical up to about 25 ft in height.
Use much less concrete than gravity walls, but require more design and careful construction.
Counter fort retaining walls are more economical than cantilever walls for heights above 25 ft.

Max Hight of cantilever retaining wall 6 m if height more then 6m then counterfort retaining wall is required. Counterfort wall more efficient to reduce earth pressure.

Every wall height is 3 meter. Then how 6 meter is correct? Anybody tell me please.

More than 6 m will become uneconomical and unstable.

Cantiliever beam are beam which are fixed one end and other end free.

Reinforced cantilever walls have an economic height range of 1.200 to 6.000 m; walls in excess of this height have been economically constructed using prestressing techniques.

If it exceeds more than 5 m. What happens to the retaining wall?

I believe that this conjecture that cantilever retaining wall cannot be used for height less than 5m is logically incorrect owing to the fact that with the increase in the span of the cantilever wall, the maximum bending moment at the support will increase thereby making it necessary to increase the thickness of the wall. Even for wall of height greater than 5m, let us say 6m, the thickness of the wall required may be higher and also the base area of the wall for the stability conditions like against overturning, sliding etc. Can also be checked and the wall as overall may come out safe depending upon the design and geometry of the wall. For instance, a shear key may be provided to take into account the sliding force and similarly for overturning, the dimensions of heel and toe slab can be adjusted accordingly.

I also want to know whether there is a standard recommendation on the maximum height of a cantilever retaining wall. If yes, then kindly enlighten me about the same.