Design of dissipative and elastic high-strength exoskeleton solutions for sustainable seismic upgrades of existing RC buildings

Almost 40% of the European building stock is in need of major energy, structural, and architectural upgrades and is responsible for a significant impact on the environment. Recent research has thus highlighted the need for a new sustainable approach for upgrading existing buildings which are technically sound while fostering safety and environmental, social, and economic sustainability. In this paper, a new method for the design of alternative solutions for a sustainable seismic upgrade of existing RC buildings is proposed. New principles for the design of sustainable and feasible structural solutions are first defined and translated into qualitative criteria and quantitative design target demand parameters to be used in a first pre-screening of possible interventions and in a following multi-objective Performance Based Design (PBD) method. A 4-step procedure for the design of alternative dissipative and high-strength exoskeletons is then presented, which enables the design of solutions leading to equivalent seismic performances of the retrofitted buildings. The proposed method is finally applied to a typical post-WWII RC building, and merits and shortcomings of dissipative and high-strength solutions are discussed. It is found that the proposed approach is capable of enforcing sustainability-driven criteria effectively for all the proposed solutions.