@article{ryu_kwag_ju_2018, title={Fragility Assessments of Multi-Story Piping Systems within a Seismically Isolated Low-Rise Building}, volume={10}, ISSN={["2071-1050"]}, DOI={10.3390/su10103775}, abstractNote={A successful, advanced safety design method for building and piping structures is related to its functionality and sustainability in beyond-design-basis events such as extremely strong ground motions. This study develops analytical models of seismically isolated building-piping systems in which multi-story piping systems are installed in non-isolated and base-isolated, low-rise buildings. To achieve the sustainable design of a multi-story piping system subjected to strong ground motions, Triple Friction Pendulum (TFP) elements, specifically TFP bearings, were incorporated into the latter building structure. Then, a seismic fragility analysis was performed in consideration of the uncertainty of the seismic ground motions, and the piping fragilities for the seismically non-isolated and the base-isolated building models were quantified. Here, the failure probability of the piping system in the non-isolated building was greater than that in the seismically isolated building. The seismic isolation design of the building improved the sustainability and functionality of the piping system by significantly reducing the seismic energy of extreme ground motions which was input to the building structure itself.}, number={10}, journal={SUSTAINABILITY}, author={Ryu, Yonghee and Kwag, Shinyoung and Ju, Bu-Seog}, year={2018}, month={Oct} }
 @article{ju_gupta_ryu_2017, title={Piping Fragility Evaluation: Interaction With High-Rise Building Performance}, volume={139}, ISSN={["1528-8978"]}, DOI={10.1115/1.4034406}, abstractNote={Many recent studies have emphasized the need for improving seismic performance of nonstructural systems in critical facilities in order to reduce the damage as well as to maintain continued operation of the facility after an earthquake. This paper is focused on evaluating system-level seismic fragility of the piping in a representative high-rise building. Piping fragilities are evaluated by incorporating the nonlinear finite-element model of a threaded Tee-joint that is validated using experimental results. The emphasis in this study is on evaluating the effects of building performance on the piping fragility. The differences in piping fragility due to the nonlinearities in building are evaluated by comparing the fragility curves for linear frame and nonlinear fiber models. It is observed that as nonlinearity in the building increases with increasing value of peak ground acceleration, the floor accelerations exhibit a reduction due to degradation/softening. Consequently, the probabilities of failure increase at a slower rate relative to that in a linear frame. It is also observed that a piping located at higher floor does not necessarily exhibits high fragilities, i.e., the fundamental building mode is not always the governing mode. Higher order building modes with frequencies closest to critical piping modes of interest contribute more significantly to the piping fragility. Within a particular building mode of interest, a good indicator of the amplification at different floor levels can be obtained by the product of mode shape ordinate and modal participation factor. Piping fragilities are likely to be higher at floor levels at which this product has a higher value.}, number={3}, journal={JOURNAL OF PRESSURE VESSEL TECHNOLOGY-TRANSACTIONS OF THE ASME}, author={Ju, Bu Seog and Gupta, Abhinav and Ryu, Yong Hee}, year={2017}, month={Jun} }
 @article{ryu_gupta_jung_ju_2016, title={A Reconciliation of Experimental and Analytical Results for Piping Systems}, volume={16}, ISSN={["2093-6311"]}, DOI={10.1007/s13296-016-0019-6}, number={4}, journal={INTERNATIONAL JOURNAL OF STEEL STRUCTURES}, author={Ryu, Yonghee and Gupta, Abhinav and Jung, WooYoung and Ju, BuSeog}, year={2016}, month={Dec}, pages={1043–1055} }
 @article{jung_kwon_ju_2016, title={Evaluation of compressive strength of concrete members laterally confined by various FRP composites and exposed to high temperatures}, volume={20}, number={6}, journal={KSCE Journal of Civil Engineering}, author={Jung, W. and Kwon, M. and Ju, B.}, year={2016}, pages={2410–2419} }
 @article{ryu_jung_ju_2016, title={Vibration effects of nonclassically damped building-piping systems subjected to extreme loads}, journal={Shock and Vibration}, author={Ryu, Y. and Jung, W. and Ju, B.}, year={2016} }
 @article{jung_ju_2015, title={Effect of MDOF structures' optimal dampers on seismic fragility of piping}, volume={9}, number={3}, journal={Earthquakes and Structures}, author={Jung, W. Y. and Ju, B. S.}, year={2015}, pages={563–576} }
 @article{ju_jung_noh_2015, title={Probabilistic risk assessment: Piping fragility due to earthquake fault mechanisms}, journal={Mathematical Problems in Engineering}, author={Ju, B. S. and Jung, W. and Noh, M. H.}, year={2015} }
 @article{ju_gupta_2015, title={Seismic fragility of threaded Tee-joint connections in piping systems}, volume={132}, ISSN={["1879-3541"]}, DOI={10.1016/j.ijpvp.2015.06.001}, abstractNote={This paper proposes a methodology to evaluate seismic fragility of threaded Tee-joint connections found in typical hospital piping systems. Existing experimental data on threaded Tee-joints of various sizes subjected to monotonic and cyclic loading indicates that the “First Leak” damage state is observed predominantly due to excessive flexural deformations at the Tee-joint section. The results of the monotonic and cyclic loading tests help us evaluate the characteristics for a given pipe size and material. A non-linear finite element model for the Tee-joint system is formulated and validated with the experimental results. It is shown that the Tee-joint section can be satisfactorily modeled using non-linear rotational springs. The system-level fragility of the complete piping system corresponding to the “First Leak” damage state is determined from multiple time-history analyses using a Monte-Carlo simulation accounting for uncertainties in demand.}, journal={INTERNATIONAL JOURNAL OF PRESSURE VESSELS AND PIPING}, author={Ju, Bu Seog and Gupta, Abhinav}, year={2015}, pages={106–118} }
 @article{ju_jung_2013, title={Seismic fragility evaluation of multi-branch piping systems installed in critical low-rise buildings}, volume={6}, number={4}, journal={Disaster Advances}, author={Ju, B. and Jung, W.}, year={2013}, pages={59–65} }
 @article{ju_jung_ryu_2013, title={Seismic fragility evaluation of piping system installed in critical structures}, volume={46}, number={3}, journal={Structural Engineering and Mechanics}, author={Ju, B. S. and Jung, W. Y. and Ryu, Y. H.}, year={2013}, pages={337–352} }
 @inproceedings{ju_tadinada_gupta_2012, title={Fragility analysis of threaded T-joint connections in hospital piping systems}, booktitle={Proceedings of the ASME Pressure Vessels and Piping Conference, PVP 2011, vol 8}, author={Ju, B. S. and Tadinada, S. K. and Gupta, A.}, year={2012}, pages={147–155} }
 @article{lucovsky_fulton_ju_stoute_tao_aspnes_luening_2006, title={Suppression of Jahn-Teller term-split band edge states in the x-ray absorption spectra of non-crystalline Zr silicates and Si oxynitride alloys, and alloys of ZrO2 with Y2O3}, volume={75}, ISSN={["0969-806X"]}, DOI={10.1016/j.radphyschem.2006.05.004}, abstractNote={Jahn–Teller (J–T) term-split states in nanocrystalline transition metal and trivalent rare earth elemental and complex oxides reduce the band gap, and tunnelling barrier height at interfaces with crystalline Si substrates. These states are identified by x-ray absorption spectroscopy and spectroscopic ellipsometry. Alloys for suppression of J–T d-state degeneracy removal are identified as: (i) non-crystalline Zr/Hf silicates and Si oxynitrides and (ii) ZrO2–Y2O3 alloys with high concentrations of randomly distributed O-vacancies that promote cubic crystalline symmetry.}, number={11}, journal={RADIATION PHYSICS AND CHEMISTRY}, author={Lucovsky, G. and Fulton, C. C. and Ju, B. S. and Stoute, N. A. and Tao, S. and Aspnes, D. E. and Luening, J.}, year={2006}, month={Nov}, pages={1591–1595} }