I have an instance where a vertical concrete wall will extend at least six feet above grade (landward side; the mudline on the seward side is about 10 feet below landward grade, thus the wall is about 16 feet high) and will be subject to direct wave impacts. The concrete wall is to be no greater than two feet thick. The return period is a 100-year storm.
The wave force, computed by the Minikin method, has a resultant of 69 kips/ft of wall. The location of the force's resultant is 14 feet above the mudline.
Constraints: the seawall is to be a vertical bulkhead-type wall with minimal excavation allowed; that is, it's not allowed to be a T-wall. NB: scour protection will be incorporated into the design.
Idea: Make it an I-wall.
Questions: OK, so it's an I-wall. What's the required section modulus of my steel that extends into the ground forming the "I"? Etc.
Other info: I am of the mind that the configuration desired is impossible. What do you folks think?