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Abstract Damage caused by earthquakes to buildings and their contents (e.g., sensitive equipment) can impact life safety and disrupt business operations following an event. Floor isolation systems (FISs) are a promising retrofit strategy for protecting vital building contents. In this study, real‐time hybrid simulation (RTHS) is utilized to experimentally incorporate multi‐scale (building–FIS–equipment) interactions. For this, an experimental setup representing one bearing of a rolling pendulum (RP) based FIS is studied—first through characterization tests and then through RTHS. A series of tests was conducted at the Natural Hazards Engineering Research Infrastructure (NHERI) Experimental Facility at Lehigh University. Multiple excitations were used to study the experimental setup under uni‐axial loading. Details of the experimental testbed and test protocols for the characterization and RTHS tests are presented, along with results from these tests, which focused on the effect of different rolling surface treatments for supplemental damping, the FIS–equipment and building–FIS interactions, and rigorous evaluation of different RP isolation bearing designs through RTHS. 

This report evaluates the dynamic response of structures using designed 3D-printed components. It is divided into four challenges, where each addresses different aspects of structural dynamics. Challenge 1 involves designing a wheel that can achieve a low angular acceleration, while exploring the principles of rotational motion. In Challenge 2, a shake table is created using a reciprocating motion system machine to convert rotational motion into linear or ground motion beneath a structure. Challenge 3 includes various free vibration tests conducted at a targeted natural frequency, achieved through the design of structural columns. Finally, Challenge 4 builds upon what was done in Challenges 2 and 3, by testing the structure’s displacement and transmissibility when subjected to forced vibrations generated by the shake table in Challenge 2. 

The 3D-printing Dynamics Design (3D3) Competition intends to train School of Civil Engineering & Environmental Science (CEES) undergraduates at the University of Oklahoma in fundamental concepts related to vibrations, structural dynamics, and earthquake engineering through a semester-long, hands-on competition run in parallel with Introduction to Dynamics for Architectural and Civil Engineers (CEES 3263). Competition participants, or 3D3 Scholars, design, build, and test a bench-scale shake table using 3D-printed components. The designs of these shake tables are published here, along with all the STL files needed for teachers or students elsewhere to fabricate the tables. Also, the data collected during the challenges is published. 

Structural dynamics is the study of the behavior of structures under dynamic loads and forces. This report displays various concepts in dynamics by creating and testing 3D printed models designed and tested with certain goals. The project is organized into four Challenges, each exploring a specific dynamics concept. Challenge 1 analyzes angular acceleration and inertia’s impact on a wheel. Challenge 2 is based around designing and testing a reciprocating motion device capable of turning rotational displacement into linear displacement. Challenge 3 focuses on designing a small structure’s columns to have a specific natural frequency. Challenge 4 combines the reciprocating motion device and the structure from the previous two challenges to make a shake table. This shake table tests the structure at several different forcing frequencies to observe the impact that the forcing frequency has on the displacement at the top of the structure.The 3D-printing Dynamics Design (3D3) Competition intends to train School of Civil Engineering & Environmental Science (CEES) undergraduates at the University of Oklahoma in fundamental concepts related to vibrations, structural dynamics, and earthquake engineering through a semester-long, hands-on competition run in parallel with Introduction to Dynamics for Architectural and Civil Engineers (CEES 3263). Competition participants, or 3D3 Scholars, design, build, and test a bench-scale shake table using 3D-printed components. The designs of these shake tables are published here, along with all the STL files needed for teachers or students elsewhere to fabricate the tables. Also, the data collected during the challenges is published. 

This report will explore concepts regarding structural dynamics through the utilization of a 3-D printed structure. The report has been broken into 4 challenges, each with its own concept being investigated. Within Challenge 1, a wheel was designed and printed to generate the lowest possible angular acceleration while gathering examining the theory behind rotational motion. Challenge 2 explored cyclical motion as this is where the shake table was designed and constructed. This challenge allowed for an understanding of how ground motion can be generated under a structure. Challenge 3 consisted of free vibration tests through the design of columns with a targeted natural frequency. Challenge 4 compounded off of Challenge 2 and Challenge 3 when the structure was subjected to forced, cyclical motion, from the shake table in order to explore concepts such as displacement and transmissibility generated from a structure subjected to forced vibration.The 3D-printing Dynamics Design (3D3) Competition intends to train School of Civil Engineering & Environmental Science (CEES) undergraduates at the University of Oklahoma in fundamental concepts related to vibrations, structural dynamics, and earthquake engineering through a semester-long, hands-on competition run in parallel with Introduction to Dynamics for Architectural and Civil Engineers (CEES 3263). Competition participants, or 3D3 Scholars, design, build, and test a bench-scale shake table using 3D-printed components. The designs of these shake tables are published here, along with all the STL files needed for teachers or students elsewhere to fabricate the tables. Also, the data collected during the challenges is published. 

The goal of this project is to gain a better understanding of the importance of structural integrity and how structures behave under motion. This report intends to investigate and analyze structural dynamics’ concepts with 3-D printed components in four unique challenges. Challenge 1 explores angular acceleration and rotational dynamics through a 3-D printed wheel. Challenge 2 focuses on reciprocating motion by designing and assembling a mechanism that is connected to a 3-D printed shake table. Challenge 3 involves creating structural columns which are assembled in a single-story structure. It also dives into concepts such as the natural frequency of a structure and how elements of design will influence it. Challenge 4 incorporates both Challenges 2 and 3 by shaking the single-story structure through the reciprocating motion mechanism. It also looks at important structural dynamics’ concepts such as transmissibility and resonance.The 3D-printing Dynamics Design (3D3) Competition intends to train School of Civil Engineering & Environmental Science (CEES) undergraduates at the University of Oklahoma in fundamental concepts related to vibrations, structural dynamics, and earthquake engineering through a semester-long, hands-on competition run in parallel with Introduction to Dynamics for Architectural and Civil Engineers (CEES 3263). Competition participants, or 3D3 Scholars, design, build, and test a bench-scale shake table using 3D-printed components. The designs of these shake tables are published here, along with all the STL files needed for teachers or students elsewhere to fabricate the tables. Also, the data collected during the challenges is published. 

The report involves the application and testing of dynamics concepts through the use of 3D-printed components. It includes various challenges promoting innovation and critical thinking. Challenge 1 focused on exploring angular motion through the design of a 3D-printed wheel. In Challenge 2, a shake table was developed by creating a reciprocating mechanism that converted rotational-to-linear motion. The kinematic relations of the 3D model were derived from the geometry of the mechanism to meet a targeted acceleration. Challenge 3 applied structural dynamics concepts by designing columns of a structure to meet a natural frequency. Challenge 4 built upon previous challenges to test a structure and shake table under forced vibrations. The results from the experiment were used to analyze the dynamic response of a structural system. The challenges integrated 3D design and mathematical modeling to understand the importance of dynamic behaviors in structural engineering.The 3D-printing Dynamics Design (3D3) Competition intends to train School of Civil Engineering & Environmental Science (CEES) undergraduates at the University of Oklahoma in fundamental concepts related to vibrations, structural dynamics, and earthquake engineering through a semester-long, hands-on competition run in parallel with Introduction to Dynamics for Architectural and Civil Engineers (CEES 3263). Competition participants, or 3D3 Scholars, design, build, and test a bench-scale shake table using 3D-printed components. The designs of these shake tables are published here, along with all the STL files needed for teachers or students elsewhere to fabricate the tables. Also, the data collected during the challenges is published. 

Protecting both the essential building contents and the structural system—as well as facilitating and accelerating the post-event functionality of business operations—is a major concern during natural hazards. Floor isolation systems (FIS) with rolling pendulum bearings along with nonlinear fluid viscous dampers (NFVD) have been proposed to mitigate damage and enhance the resiliency of non-structural and structural systems, respectively. These devices are designed to decrease vibrations under dynamic loading conditions. In this poster, we introduce research using tridimensional nonlinear cyber-physical experimental testing (i.e., real-time hybrid simulations) to validate the performance of these response modification devices placed in structural systems under wind and earthquake loading conditions. The effects of soil-structure-foundation and fluid-structure interactions were also accounted for. The novelty of the project is the use of multi-directional large-scale real-time hybrid simulations of complex nonlinear systems under wind and earthquake demands to combine experimental structural modification passive devices with analytical multi-story buildings considering soil-foundation interaction via neural network. Results show that the FIS and NFVD can significantly reduce the demand on non-structural and structural systems of buildings subjected to natural hazards whose response can be also significantly affected by soil-foundation-structure interaction. A product of this research is the data (which is linked in Related Works), which can be used to compare with new studies using the same experimental techniques and structural modification devices or with alternative approaches. Researchers interested in multi-natural hazards resilience and mitigation, state-of-the-art structural experimental techniques, and the use of machine learning as a tool to improve modeling efficiency will benefit from its results. Also, companies dedicated to the commercial development of structural response modification devices, as well as policymakers working or with interest in economic and social resilience.