Optimization of the energy performance of building envelopes accounting for structural constraints

This work presents the optimization of the energy performance of building envelopes made of NRG&STRUCT foams, which are foamed concretes with microencapsulated phase change material (mPCM). Layer-wise graded NRG&STRUCT-foams are used in external walls. At each layer, the material is characterized by its porosity and mPCM content, which play the role of design variables to be determined by solving an optimization problem where the objective function is the energy consumption for keeping the indoor thermal comfort, computed by EnergyPlus. These design variables are continuous, allowing the use of gradient-based optimization solvers. The structural stability of the energetically optimal solutions is forced via constraints on minimal density. © Fédération Internationale du Béton-International Federation for Structural Concrete.