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The Natural Hazards Engineering Research Infrastructure (NHERI) Converging Design project is a collaborative effort between multiple universities and industry entities with the goal of creating a new design paradigm in structural engineering that employs multi-objective optimization to maximize functional recovery while integrating sustainability principles in the design process. The structural design approaches were validated through full-scale shake table testing of a 6-story mass timber structure at the at the Englekirk Structural Engineering Center at University of California, San Diego (NHERI@UCSD) Large High-Performance Outdoor Shake Table (LHPOST6) facility for eventual inclusion in a multi-objective design optimization framework. The shake table testing included three phases. Phase one consisted of a mass timber self-centering rocking wall (SCRW) system with U-shaped flexural plates (UFPs) in both building horizontal directions. Phase two replaced the SCRWs in one principal direction with SCRWs with buckling restrained boundary elements (BRBs) at the first story. Phase three replaced the newer walls from phase two with a resilient steel moment frame and concentric braced-frame (MF/CBF). The data shared includes reports summarizing the testing program, structural drawings, instrumentation setups, and raw data for the series of shake table tests performed during each phase. The data include building responses due to shake table motions simulating scaled historical ground motions and white noise (WN) tests. 

Numerical analyses can aid design exploration, but there are several computational approaches available to consider design options. These range from “brute-force” search to optimization. However, the implementation of optimization can be challenging for the complex, time-intensive analyses required to assess seismic performance. In response to this challenge, this study tests several optimization strategies for the direct displacement-based design of a lateral force-resisting system (LFRS) using mass timber panels with U-shaped flexural plates (UFPs) and post-tensioning high-strength steel rods. The study compares two approaches: (1) a brute-force sampling of designs and data filtering to determine acceptable solutions; and (2) various automated optimization algorithms. The differential evolution algorithm was found to be the most efficient and robust approach, saving 90% of computational cost compared to bruteforce sampling while producing comparable solutions. However, every optimization formulation did not return best range of design options, often requiring reformulation or hyperparameter tuning to ensure effectiveness. 

To address functional recovery after earthquakes, there is growing interest in developing enhancedperformance seismic-resisting systems. Rocking walls, featuring a base gap-opening mechanism and designed to remain essentially elastic above the base, have demonstrated their potential in various construction materials, including mass timber. If combined with steel energy dissipators, the resulting hybrid steel-mass timber rocking walls have emerged as a promising seismic-resisting system. This study focuses on Post-Tensioned Mass Timber Rocking Walls supplemented with Buckling-Restrained Brace (BRB) boundary elements and builds upon findings from experimental programs funded by the National Science Foundation (NSF) and the United States Department of Agriculture (USDA). The rocking mechanism, controlled by the BRBs and the Post-Tensioned (PT) rods, provides self-centering behaviour, reducing the potential for residual drifts and improving post-earthquake repairability. An estimating method for higher-mode loading profiles is proposed and applied to a six-story archetype, which was tested at the Large High Performance Outdoor Shake Table (LHPOST) at the University of California San Diego (UCSD) in January 2024 as part of the NHERI Converging Design Project. The estimating method is practically formulated to facilitate the implementation in design procedures. 

Numerical analyses can aid design exploration, but there are several computational approaches available to consider design options. These range from “brute-force” search to optimization. However, the implementation of optimization can be challenging for the complex, time-intensive analyses required to assess seismic performance. In response to this challenge, this study tests several optimization strategies for the direct displacement-based design of a lateral force-resisting system (LFRS) using mass timber panels with U-shaped flexural plates (UFPs) and post-tensioning high-strength steel rods. The study compares two approaches: (1) a brute-force sampling of designs and data filtering to determine acceptable solutions, and (2) various automated optimization algorithms. The differential evolution algorithm was found to be the most efficient and robust approach, saving 90% of computational cost compared to brute-force sampling while producing comparable solutions. However, every optimization formulation did not return best range of design options, often requiring reformulation or hyperparameter tuning to ensure effectiveness. 

This paper presents the statistical and numerical investigation of the seismic performance of a three-story post-tensioned mass ply panel (MPP) rocking wall lateral force-resisting system prototype whose main components are MPP, U-shaped flexural steel plates (UFPs), and high-strength steel post-tensioned rods. Uncertainties in material properties and geometry of the components are considered in the assessment of the performance of this lateral forceresisting system based on recent experimental data on MPP, experimental data available in the literature for the UFPs and post-tensioning rods, as well as some additional structural design considerations. In the assessment of the seismic performance factors, first, random realizations of the structural design are generated using Monte Carlo simulation. Second, for each realization, a nonlinear finite element model is developed. For each realization, two types of analysis are performed, nonlinear static analyses, and incremental dynamic analyses. Results of the nonlinear static and dynamic analyses are then used to estimate the seismic design factors (e.g., R-factor) and limit state-based fragility functions, the latter being based on exceeding limit states defined for each component based on existing experimental data. 

This paper describes the lateral force resisting system (LFRS) design in a full-scale six-story shake-table test building and presents a comparative cradle-to-grave life-cycle assessment of alternative LFRSs. The test building features the reuse of material from a ten-story shake-table structure comprised of engineered mass timber (MT) products. These include MT floors (cross-, glue-, nail-, and dowel-laminated timber [CLT], [GLT], [NLT], [DLT]); MT posttensioned rocking walls (CLT and mass ply panels [MPP]); and a gravity system consisting of laminated-veneer lumber (LVL) beams and columns. Shake-table testing will benchmark innovative, low-damage design solutions for the LFRSs. To supplement this test, the environmental impact of a MT LFRS is determined relative to design alternatives that use conventional materials. The Athena Impact Estimator for Buildings was used to perform a comparative, cradle-to-grave life-cycle assessment (LCA) of the prototype MT LFRS with respect to an alternative, functionally equivalent reinforced concrete (RC) shear wall design. The LCA results showed reduced environmental impacts across some impact metrics, with a significant reduction in Global Warming Potential for the MT LFRS when accounting for biogenic carbon.