@article {bnh-7464, title = {Collapse probability of soft-storey building in Australia and implications for risk-based seismic design}, journal = {Australian Journal of Structural Engineering}, year = {2020}, month = {10/2020}, pages = {1-13}, abstract = {

Collapse prevention is the primary objective of earthquake-resistant design of structures; hence, the probability of collapse should be taken as a crucial performance indicator for risk-based design of new structures or assessment of existing structures. One major challenge in collapse risk assessment is to reliably model the non-linear structural response behaviour. This study features the rocking response behaviour of precast reinforced concrete (RC) columns based on results from previous field testing on parts of a real building and supplemented with a study of their rocking behaviours through a series of shake-table tests. The effects of bidirectional earthquake actions on failure drift capacity of columns have also been incorporated, such that realistic estimates of displacement capacity were made for constructing collapse fragility functions, which were then combined with the ground motion recurrence relationships of Melbourne, Australia for the computation of collapse probability. A suite of typical soft-storey buildings was adopted, with considerations given to a diversity of site conditions. Deaggregation of the results reveals the range of return periods that controls the collapse risk, which could have important implications for the choice of earthquake scenarios for seismic analysis and design in regions of lower seismicity.

}, keywords = {Collapse Probability, drift capacity, Return Period, Risk-based Seismic Design, soft-storey building}, doi = {https://doi.org/10.1080/13287982.2020.1835157}, url = {https://www.tandfonline.com/doi/abs/10.1080/13287982.2020.1835157}, author = {Hing-Ho Tsang and John Wilson and Emad F Gad} } @article {bnh-5009, title = {Seismic retrofit of precast soft-storey building using diagonal steel-shape memory alloy bracing device: Numerical investigation}, journal = {Advances in Structural Engineering}, year = {2018}, month = {10/2018}, abstract = {

A diagonal steel-shape memory alloy bracing device is proposed for seismic retrofitting of vulnerable building frame structure. Superelastic shape memory alloy bar is put in series with steel bars in the bracing. The device makes use of the loading plateau of superelastic shape memory alloy to limit the tensile force of diagonal bracing. A precast soft-storey building frame in Australia was selected for a case study. A numerical model of the frame was developed and validated with the results from full-scale pull-down field tests. Nonlinear time history analysis was then conducted to evaluate the seismic performance of the frame with different retrofitting strategies. The result shows that the diagonal steel-shape memory alloy bracing can reduce the displacement demand on the soft-storey frame. Meanwhile, the level of tensile force of steel-shape memory alloy bracing can be controlled by the force plateau of the shape memory alloy bar, which is recommended to be 20\% of the yielding force of the steel bar. The lower tensile force demand could alleviate the force demand at the associated support connections.

}, keywords = {diagonal bracing, retrofit, shape memory alloy, soft-storey building, superelastic}, doi = {10.1177/1369433218800939}, url = {http://journals.sagepub.com/doi/abs/10.1177/1369433218800939}, author = {John Wilson and Hing-Ho Tsang and Xiaoxian Liu} }