An alternative procedure for seismic evaluation and strengthening of tall buildings

Abstract

SUMMARYThe goal of existing building codes and standards for the evaluation and strengthening of existing buildings is to provide for safe buildings by prescribing loads and material properties and structural analysis methods for a broad spectrum of building heights, types and construction. Experience clearly shows that building codes and standards do not provide for the most economical, efficient and safe tall buildings because the codes are general and prescriptive in nature and do not allow the structural engineer the flexibility without significant difficulty to incorporate building-specific applicable experience, education and new technologies. Tall buildings are really a special class of buildings that have unique qualities and characteristics. The design of tall buildings has been recognized by the structural engineering profession to require more care and effort in both design and construction because of the need to meet safety and performance requirements. This recognition is based in part on the large number of people at risk in tall buildings and also the negative financial impact on the community and the building owner. To meet this need, an alternative procedure for Seismic Evaluation and Strengthening of Existing

Performance‐based evaluation and strengthening of tall buildings in the Los Angeles region by using Bayesian structural reliability

“…The above may lead the reader to believe that each Bayesian analysis is too much effort. This is not true because the equations developed in this paper and LATB‐2 (Hart et al ., 2012c) can be programmed in a spreadsheet with essentially no run time. Also, it is possible to perform sensitivity analyses of the Bayesian analysis results to assist in planning tests and computer modeling and analysis sophistications.…”

“…The presentation of two of the four options provides the necessary development to let the reader see the benefit of the Bayesian approach. Options 3 and 4 are contained as noted above in LATB‐2 (Hart et al ., 2012c). Before proceeding, the reader may be thinking—Why do I need options 1 and 3 because they are just special cases of options (2) and (4)?…”

“…The current approach and foundation for the existing building procedure is described in three journal papers: Hart et al . (, ) and Delli Quadri et al . ().…”

The importance in a global world of a structural reliability-based foundation for seismic evaluating and strengthening tall and special buildings

“…Like structural analysis, they range from spreadsheet calculations to very sophisticated computer‐based solutions and thus like structural mechanics‐based structural analysis options offer for a specific project, or phases in a project, different options. To illustrate this, consider a structural reliability foundation‐based approach using options identified in prior papers published in this journal (Delli Quadri et al, ; Hart et al, ; Hart et al, ).…”

“…The prescribed load demand (D PL ) and capacity equation for the limit state (Hart, ; Hart et al, ; Brandow et al, ; Hart et al, ) can be expressed as …”