Analytical Prediction of the Seismic Performance of Masonry Infilled Reinforced Concrete Frames Subjected to Near-Field Earthquakes

摘要

In the recent past, a number of ground motions with large velocity pulses have been recorded in the near-field regions of earthquakes. A ground motion recorded in the near-field region of a strike-slip earthquake (i.e., near the fault rupture of the earthquake) exhibits distinctive long-period velocity pulses that are characteristic of near-field earthquakes and are not found in far-field ground motion records. The present study is based on analytical evaluation of the effect of distribution of masonry infill panels over the elevation of planar masonry-infilled RC frames on the seismic response of the frame subjected to near-field earthquakes implementing rational seismic analysis methods within the performance-based framework such as nonlinear dynamic time-history analysis and nonlinear static force-displacement (push-over) analysis using realistic and efficient computational models. Despite intense worldwide research in the area of masonry infilled frame structures during the past few decades, displacement-based nonlinear analyses of masonry infilled frames with explicit consideration of infill panels as structural elements is far from common practice, mostly due to the analytical complexity in modeling the infill panel realistically. The displacements are of particular interest from the viewpoint of performance-based design (PBD), the emerging model for the next generation of standard codes of practice for earthquake-resistant design. One of the objectives of the study is to demonstrate rational displacement-based analysis methodologies within the performance-based framework for accurately and efficiently predicting the global and local seismic demands and related intensity of seismic damage in practical masonry infilled multistory RC framed construction with seismically undesirable vertical layouts of masonry panels under the influence of near-field earthquakes.