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This dataset contains data from E-Defense shake-table tests of a full-scale, steel moment-resisting frame (MRF) supplemented with spines. Herein, the spines were pin-based columns with sufficient stiffness and strength to distribute plastic deformation evenly over the height of the MRF. The specimen was tested under two configurations: first, with the spine rigidly connected to the MRF; and second, with the spine connected to the MRF through Force-Limiting Connections (FLCs). The two structural systems were subjected to two ground motions adjusted to two different scales. The tests highlighted the expected benefits of spines as well as their drawbacks of inducing large floor acceleration in the MRF and large shear forces in the spines themselves. The tests also highlighted how the FLCs can mitigate such drawbacks of spines. The data may be used, for example, to reproduce the observations presented by the authors, to compare the dynamic response of the specimen with building specimens tested in other shake-table test programs, to validate numerical models against the measured specimen response, or to formulate classroom exercises on system identification of linear and nonlinear systems. 

Mid-rise moment resisting frames (MRF) which utilize supplemental pinned-base spines (spine) to prevent the formation of story mechanisms experience higher mode accelerations at near elastic spectral values. Force Limiting Connections (FLC) can be introduced to reduce the floor accelerations from the higher mode responses while having small impact on first-mode response and maintaining the story mechanism prevention from the spine. Results from nonlinear response history analysis (NRHA) of a 4-story MRF-Spine system show how floor accelerations for higher modes are reduced with the addition of FLC placed between the MRF and spine. Peak effective pseudo accelerations are utilized to show how pseudo spectral accelerations are reduced by the introduction of FLC. Full-scale testing of the 4-storyMRF-Spine structure supports the numerical results of theMRF-Spine andMRF-Spine-FLC numerical analyses. These results show the potential benefits of adding FLC to MRF-Spine systems. 

Electrotactile stimulus is a form of sensory substitution in which an electrical signal is perceived as a mechanical sensation. The electrotactile effect could, in principle, recapitulate a range of tactile experience by selective activation of nerve endings. However, the method has been plagued by inconsistency, galvanic reactions, pain and desensitization, and unwanted stimulation of nontactile nerves. Here, we describe how a soft conductive block copolymer, a stretchable layout, and concentric electrodes, along with psychophysical thresholding, can circumvent these shortcomings. These purpose-designed materials, device layouts, and calibration techniques make it possible to generate accurate and reproducible sensations across a cohort of 10 human participants and to do so at ultralow currents (≥6 microamperes) without pain or desensitization. This material, form factor, and psychophysical approach could be useful for haptic devices and as a tool for activation of the peripheral nervous system. 

ABSTRACT This data paper presents data obtained from E‐Defense shake‐table tests of a full‐scale, steel moment‐resisting frame (MRF) supplemented with Spines. Herein, the Spines were pin‐based columns with sufficient stiffness and strength to distribute plastic deformation evenly over the height of the MRF. The specimen was tested under two configurations: first, with the Spine rigidly connected to the MRF; second, with the Spine connected to the MRF through force‐limiting connections (FLCs). Each specimen configuration underwent earthquake simulations using ground motions with two scale factors. The tests demonstrated the expected benefits of Spines as well as the disadvantage of inducing large floor accelerations in the structure and large shear forces in the Spines. The tests also demonstrated how the FLCs can mitigate these disadvantages. This data paper reports an overview of the tests, data archive structure, and potential use of the data. The data can be used, for example, to reproduce the observations presented by the authors, to compare the dynamic response of the specimen with building specimens tested in other shake‐table test programs, to validate numerical models against the measured specimen response, or to formulate classroom exercises on system identification of linear and nonlinear systems. 

Numerical modeling is widely used in structural engineering to represent buildings response under seismic loading conditions. However, even though numerical modeling is a common tool to characterize the behavior of structures, modeling uncertainties can lead to a broad range of expected response, particularly when representing the behavior of novel systems or components. Addressing different modeling choices can provide more informed insights into the response of structures, especially prior to conducting experimental tests or participating in blind prediction contests. Herein, blind response prediction of a novel steel system was conducted before testing at the E-Defense facility in Japan. The full-scale specimen consisted of a weak Moment-Resisting Frame (MRF) retrofitted with steel spines and force-limiting connections (FLC). The set of pre-test predictions involved addressing of different modeling choices to overcome the many sources of epistemic uncertainties and to provide greater confidence in the design and experimental testing program. Several models were subjected to the records specific to the testing program (Northridge Sepulveda and JMA Kobe) to estimate drift and acceleration responses. Numerical results were compared to the experimental data from the shake-table tests. Although all the models were able to represent general trends in drifts and accelerations and enabled proper development of the testing plan, peak response varied significantly depending on the modeling choices, especially those altering the system’s natural periods or those leading to different yielding patterns. 

Conventional lateral force-resisting systems can provide a stable, ductile response but also experience significant inelastic demands, rendering repairs impractical or uneconomical. Thus, there is a need for novel structural systems that protect structural and nonstructural components to reduce post-earthquake repairs and downtime. A U.S.-Japan research team – including three U.S. universities, two Japanese universities, and two major experimental research labs – is developing a structural solution to reduce peak drift and acceleration demands, thereby protecting buildings, their contents, and occupants during major earthquakes. The primary components of the system are: (1) steel base moment-resisting frames designed and detailed to behave in the inelastic range and dissipate energy, (2) stiff and strong elastic spines designed to remain essentially elastic to redistribute seismic demands more uniformly over the building height, and (3) force-limiting connections (FLC) that connect the frame to the spines to provide a yielding mechanism that limits acceleration demands. This economical earthquake-resilient system is intended to be used in essential facilities, such as hospitals, where damage to the buildings and contents and occupant injuries must be prevented and where continuity of operation is imperative. The system was recently tested at full scale at the E-Defense shake-table facility in Miki, Japan. This paper provides an overview of pre-test numerical simulations, shake-table test setup and instrumentation, and preliminary test results. 

A new seismic-resilient structural system is being developed to protect buildings, their contents, and occupants during major earthquakes. This economical system is intended for essential facilities, such as hospitals, where damage to the buildings and contents and occupant injuries must be prevented and where continuity of operation is imperative. The primary components of the Frame-Spine-FLC System are: (1) steel base moment-resisting frames designed and detailed to behave in the inelastic range and dissipate energy, (2) stiff and strong elastic spines designed to remain essentially elastic to redistribute seismic demands more uniformly over the building height, and (3) force-limiting connections (FLC) that connect the frame to the spines to provide a yielding mechanism that limits acceleration demands. An international team, including three U.S. universities, two Japanese universities and two major experimental research labs, is collaborating on this project and recently conducted full-scale shake-table testing at the E-Defense facility in Miki, Japan. The test building represents a hospital facility and includes realistic nonstructural components and medical equipment. This paper provides an overview of the shake-table testing program and presents preliminary results that demonstrate the seismic stability response of the Frame-Spine-FLC System and the overall viability of the new concept. 

Abstract The generation of pressure perturbations in matter stimulated by pulsed light is a method widely recognized as the photoacoustic or light‐induced thermoelastic effect. In a series of psychophysical experiments, the robustness of the tactile perception generated with a variety of light sources is examined: a diverging pulsed laser used for photoacoustic tomography optical parameter oscillation (OPO), a miniature diode laser (MDL), and a commercial digital light processing (DLP) projector. It is demonstrated that participants can accurately detect, categorically describe the sensations, and discern the direction of pulsed light travel. High detection accuracy is reported as follows: (d′ = 4.95 (OPO);d′ = 2.78 (modulated MDL);d′ = 2.99 (DLP)) of the stimulus on glabrous skin coated with a thin layer of dye absorber. For all light sources, the predominant sensation is felt as vibration at the distal phalanx (i.e., fingertip, 55.21–57.29%) and the proximal phalanx (41.67–44.79%). At the fingertip, thermal sensations are perceived less frequently than mechanical ones. Moreover, these haptic effects are preserved under a wide range of pulse widths, spot sizes, optical energies, and wavelengths of the light sources. This form of sensory stimulation demonstrates a generalizable non‐contact, non‐optogenetic, in situ activation of the mechanosensory system.