A review of demountable connections in structural engineering for circular construction across materials and systems

The global construction industry’s transition to a Circular Economy (CE) requires innovative structural solutions, especially demountable connections, which enable component reuse and improve resource efficiency. This review synthesizes recent advances in demountable connection technologies and examines how they support Design for Deconstruction (DfD) across structural typologies and materials. First, it discusses the design and structural behavior of dry joints, with emphasis on bolted connections, enabling rapid assembly and reversibility in precast concrete, modular, and tubular steel buildings. The paper then critically analyses demountable shear connections in composite systems, including Steel-Concrete (SC) and Ultra-High-Performance Concrete (UHPC) beams, focusing on capacity, stiffness, ductility, and reusability after repeated disassembly and reassembly. Reversibility challenges in hybrid composites, notably Timber-Concrete Composite (TCC) systems, receive particular attention. Emerging shear-transfer solutions, such as notched connections, are reviewed for maintaining structural performance while facilitating disassembly. The conclusions highlight key barriers, achieving performance parity with monolithic systems and standardizing component reuse, and outline research priorities needed for widespread adoption of demountable structural systems in a sustainable built environment.