@article {bnh-6808, title = {Simplified calculation of roof accelerations in existing low-rise symmetric unreinforced masonry buildings with flexible diaphragms}, journal = {Bulletin of Earthquake Engineering}, year = {2020}, month = {03/2020}, abstract = {

A formulation is presented for simplified evaluation of the roof acceleration response for the purpose of assessing non-structural components in unreinforced masonry buildings with flexible diaphragms excluding torsional effects. The method is based on modal calculations that are further studied through nonlinear time-history analysis (NLTHA) of four case study buildings. The NLTHA results for a relatively small level of ground shaking was used to validate the overall ability of the simplified modal method to predict the diaphragm flexibility effects. The NLTHA results were also used to discuss the effects of the building inelastic response in the conservatism of the simplified modal technique. It was found that, in lieu of a comprehensive modal analysis, it is possible to calculate roof accelerations in symmetric low-rise buildings with flexible diaphragms using a simplified two-mode modal method. Based on this study, a predictive method is proposed for conservative estimation of peak roof accelerations in these buildings.

}, keywords = {acceleration response, flexible diagrams, height amplification factor, unreinforced masonry}, doi = {https://doi.org/10.1007/s10518-020-00823-1}, url = {https://link.springer.com/article/10.1007/s10518-020-00823-1$\#$citeas}, author = {Hossein Derakhshan and Yasuto Nakamura and Michael Griffith and Manicka Dhanasekar} } @article {bnh-6698, title = {Suitability of Height Amplification Factors for Seismic Assessment of Existing Unreinforced Masonry Components}, journal = {Journal of Earthquake Engineering}, year = {2020}, month = {01/2020}, pages = {1-20}, abstract = {

The suitability of {\textquoteleft}design{\textquoteright} height amplification factors (HAF) for the purpose of seismic assessment of existing non-structural unreinforced masonry (URM) components with known strength was evaluated through a numerical study. Four building typologies were included that represented pre-1940 URM construction in Australia and New Zealand. Through pushover and incremental dynamic analyses, the effects of diaphragm flexibility and nonlinear building response on floor accelerations were studied. It was found that Australia/New Zealand code procedures include significant inelastic building behaviour that reduces HAF. An interpretation was made on the applicability of the assumptions in the context of assessing non-structural URM components.

}, keywords = {flexible diaphragms, height amplification factor, non-structural components, seismic input, unreinforced masonry}, doi = {https://doi.org/10.1080/13632469.2020.1716889}, url = {tandfonline.com/doi/full/10.1080/13632469.2020.1716889}, author = {Hossein Derakhshan and Yasuto Nakamura and Michael Griffith and Jason Ingham} }