Structural Codes Flashcards

What maximum live load deflection does the IBC permit for floor structural members supporting plaster ceilings?

Answer: L/360

The IBC limits live load deflection of floor members supporting plaster or plaster-like ceilings to L/360 of the member's span length to prevent cracking.

Per ASCE 7, what base multiplying factor converts the ground snow load (Pg) to a flat roof snow load (Pf) before applying the exposure, thermal, and importance factors?

Answer: 0.7

ASCE 7 defines flat roof snow load as Pf = 0.7 × Ce × Ct × Is × Pg, where 0.7 is the base conversion factor accounting for snow that slides or is blown off roofs.

In seismic base shear calculations per ASCE 7, what does the 'R' factor represent?

Answer: The response modification factor reflecting a system's ductility and overstrength

The Response Modification Factor (R) allows design seismic forces to be reduced from elastic demand levels, reflecting the structural system's inherent ductility, redundancy, and overstrength.

Which chapter of the IBC establishes requirements for special inspections, structural observations, and material testing to verify structural compliance during construction?

Answer: Chapter 17 — Special Inspections and Tests

IBC Chapter 17 mandates special inspections, testing, and structural observations for critical structural elements to ensure quality and code compliance during construction.

In seismic structural design, what does 'ductility' refer to?

Answer: A structure's ability to undergo large inelastic deformations without losing its load-carrying capacity

Ductility is the capacity of a structural system or material to sustain significant inelastic deformation beyond the elastic limit while maintaining its ability to carry loads, enabling energy dissipation during earthquakes.

Under IBC seismic provisions, for which Seismic Design Categories is a geotechnical investigation generally required?

Answer: SDC C through F, where elevated seismic hazard demands site-specific soil evaluation

The IBC generally requires geotechnical investigations for structures assigned to SDC C through F to assess soil liquefaction potential, site amplification, and other seismic soil-structure interaction effects.

According to ASCE 7, how are basic wind speeds for structural design determined?

Answer: From site-specific wind speed maps that vary by geographic location and building risk category

ASCE 7 provides wind speed maps specifying design wind speeds (3-second gust, in mph) based on geographic location, with separate maps for each Risk Category to reflect varying consequence levels.