Advise regarding foam cement for use on dome structure

I am looking for a structural engineer to help me decide on the formula to use in making foam cement. The foam cement is going to be sprayed on an air form (Echoshell 1). I need advise regarding the appropriated mix of cement, water, and foam to insure the best balance of compressive strength, tensile strength, and capacity to insulate the Echoshell 1. I need to know if I should consider adding sand or fly ash. You must have a masters degree or higher in order to be considered for this job.