Expert/source verification requiredEdition-dependent or normative details must be confirmed against the adopted standard and National Annex before project use.
Design spectrumBehaviour factor qImportance contextWorked workflow
Learning objectives
In this lesson
- Never invent Nationally Determined Parameters.
- q is inseparable from system and detailing.
Engineering explanation
Worked workflow: (1) confirm country, adopted edition and National Annex; (2) obtain official hazard input; (3) establish ground classification from project evidence; (4) select the prescribed spectrum type, damping treatment and importance context; (5) justify structural system, ductility class and q; (6) construct and independently check the spectrum used by the model. The design spectrum is connected to accepted inelastic behaviour. q is therefore a system-and-detailing decision, not a convenient free reduction factor.
Key takeaways
What to carry forward
- Never invent Nationally Determined Parameters.
- q is inseparable from system and detailing.
- Archive spectrum inputs and independent checks.