Shower Base Support Reinforcement

I am doing a job for a veteran. Overweight, possibile wheel chair in future. Point loads for this man in a wheelchair are high; a concrete shower base has been suggested. Improved support is required for the floor base.
Requirements:
- Add reinforcement brackets to the existing shower base.
- Current base is tiled, so the solution must be compatible with tile.
- Brackets should be made of stainless steel.

Ideal Skills and Experience:
- Experience working with tile and shower bases.
- Knowledge of structural reinforcement techniques.
- Proficiency in working with stainless steel.