Overview
ISO 22502:2020 - Simplified design of connections of concrete claddings to concrete structures provides practical provisions for the mechanical design and structural analysis of panel-to-structure and panel-to-panel connections used in cladding systems for reinforced concrete frame buildings. Originally targeted at single‑storey, typically precast structures, the guidance can be adapted for multi‑storey buildings with appropriate modifications. The standard focuses on common fastening types - steel elements, sliding connectors, and dissipative devices (friction or plastic behaviour) - and limits the use of other fastening types unless backed by comparable experimental and analytical verification.
Key topics and requirements
- Design approaches: Defines three main design philosophies - isostatic, integrated, and dissipative - and explains when each approach is appropriate for seismic performance of cladding connections.
- System strategies: Describes practical systems such as sliding-frame (SF), double-hinged pendulum (DHP) and rocking panel (RP) to control load transfer and relative movement between panels and frames.
- Device types and detailing: Covers sliding devices, hinge connections, steel brackets, bolted plates, shear keys, hammerhead straps, cantilever box and steel angle connections, as well as dissipative solutions like friction devices, steel cushions, multi‑slit devices and folded steel plates.
- Structural analysis guidance: Offers suggestions for modelling buildings and panels, classification parameters, application procedures, and limitations on using seismic force reduction factors for cladding connections.
- Design documentation: Includes practical design flowcharts (Annex A) and procedures for the analysis and verification of conventional, integrated and dissipative connection systems.
- Limitations and validation: Prohibits use of connection types not described in the document unless supported by comparable experimental and analytical studies demonstrating equivalence.
Applications
- Ensures seismic resilience of precast and cast-in-place concrete cladding systems by defining reliable connection design methods.
- Applicable to designers developing panel-to-structure and panel-to-panel fastenings, architects specifying façade attachment strategies, and fabricators producing connection hardware.
- Useful for retrofit or strengthening projects where conventional connections are upgraded to meet seismic performance goals.
Who should use this standard
- Structural and façade engineers
- Precast concrete designers and manufacturers
- Construction detailers and façade contractors
- Code authorities and reviewers assessing cladding connection safety under seismic action
Related standards and next steps
- Consult ISO/TC 71 publications and your applicable national or regional seismic design codes for complementary requirements and load criteria.
- To implement designs, obtain the full ISO 22502:2020 document from ISO for detailed procedures, formulas and prescriptive connection details.