Ghodsi, Tony

The 2015 Los Angeles Alternative Procedure for Seismic Analysis and Design of Tall Buildings

Abstract eng:
Building codes intend to provide for safe buildings by prescribing provisions that generally address all building and construction types. Tall buildings are a special class of structures that may need to be designed with a different approach to meet their specific safety and performance requirements, especially in regions of high seismicity. To meet this need, the Los Angeles Tall Buildings Structural Design Council (LATBSDC) has recently updated its alternative procedure for seismic analysis and design of tall buildings. LATBSDC has been developing the alternative design procedure over 12 years and has recently published the 2015 edition of this procedure. Application of this performance-based alternative procedure requires an in-depth understanding of ground shaking hazards, structural materials behavior, and nonlinear dynamic structural response. The aims of the procedure are to provide: a more reliable seismic performance; reduced construction cost; relief from prescriptive design requirements that do not need to apply; accommodation of demanding architectural features; and use of innovative structural systems and materials not currently allowed by the building codes. LATBSDC has also recently published guidelines on the proper use of dual systems for tall buildings. The following major updates have been implemented in the 2015 edition which is actively being used for design of tall buildings all over the west coast of the United States: • Updated modeling requirements and acceptability criteria for reinforced concrete walls and coupling beams. • Incorporation of sensitivity analysis requirements to bound the possible ramifications of the backstay effect. • Incorporation of adjusted acceptability criteria for buildings in various seismic risk categories. • Revised design ground motion criteria which permits the use of conditional spectra. This paper describes the provisions of the 2015 edition and highlights the significance of the performance improvements that can be achieved using these new provisions for design of tall building structures.

Contributors:

Naeim, Farzad

Conference Title:

Proceedings of the 16th World Conference on Earthquake Engineering

Conference Title:

16th World Conference on Earthquake Engineering

Conference Venue:

Santiago (CL)

Conference Dates:

2017-01-09 / 2017-01-13

Rights:

Text je chráněný podle autorského zákona č. 121/2000 Sb.