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This paper presents a new stochastic methodology for evaluating and quantifying the downtime of a structure in terms of a family of fragilities that represent the probability of exceeding prescribed times to return to functionality. This methodology integrates several existing concepts, namely, Federal Emergency Management Agency P-58 and Resilience-based Earthquake Design Initiative (REDi), to build a family of system (building) level fragility curves corresponding to the time needed to achieve different recovery levels (reoccupancy, functional recovery, and full recovery). This approach enables one to propagate uncertainty throughout the procedure so that variations in the delay time and repair schedules are accounted for in the resulting fragilities. As an illustrative example of this approach, the methodology is applied to assess the downtime of a two-story mass timber building that was originally tested at the NHERI@UCSD outdoor shake table in 2017. One unique aspect of this analysis is that it incorporates a relatively new material, cross-laminated timber (CLT), in a resilient posttension rocking wall design application. Nonstructural components representing a typical office building were selected and incorporated into the procedure for the two-story CLT rocking wall building. Time-to-functionality fragility curves are then developed for the two-story building, and potential design and resilience-focused applications are discussed. [ABSTRACT FROM AUTHOR]

This paper presents the behavior of floor diaphragms of a shake-table experiment of a full-scale 2-story mass-timber building structure. The structure consists of glued-laminated timber beams and columns, and floors and walls were designed and built making use of cross-laminated timber panels. Two different floor systems were designed, where the roof consists of a topped cross-laminated timber (CLT)-concrete composite system, and the floor level consists of untopped CLT panels connected with plywood single-surface splines. The CLT floor systems were designed to remain essentially elastic over the whole series of shake-table tests, which included testing of three lateral force–resisting systems tested at three different seismic intensity levels (service level, design basis, and maximum considered earthquake) for a total of 34 shake-table earthquake tests. Results from the testing indicate that CLT diaphragms designed to remain essentially elastic based on basic principles of structural mechanics and existing test data can achieve desired seismic performance objectives. In addition, sources of overstrength in certain elements of the diaphragm need to be explicitly considered for a holistic diaphragm design. [ABSTRACT FROM AUTHOR]

Post-tensioned timber (Pres-Lam) buildings have been constructed throughout the world, beginning in 2010. The technology, which originated from low-damage concrete building applications, relies on unbonded post-tensioning tendons to provide moment capacity to beam–column, wall–foundation, or column–foundation connections. Supplemental energy dissipation can be introduced by the inclusion of mild steel bars or replaceable damping devices when designing buildings for high-seismic-risk areas. Given the increasing demand for multistory timber buildings in high seismic zones, the Pres-Lam system is recognized worldwide as one of many efficient solutions for achieving seismic-resilient and sustainable structures. This paper presents an overview of the current state-of-the-art of the Pres-Lam system, including experimental campaigns, numerical and analytical modeling, and operating buildings as well as design procedures and design procurement. [ABSTRACT FROM AUTHOR]

• Events impacting tunnel functionality are identified based on duration & intensity. • Stochastic simulation model built to evaluate the downtime of tunnel infrastructure. • Separate modeling mechanism for event types. • Functionality loss quantified using a numeric metric. • Metric is used to compute resilience of road tunnels to disruptive events generated from the model. Given the importance of road tunnels in a transportation network, it is essential to quantitatively assess and predict tunnel functionality loss due to disruptive events. In this study, a stochastic event simulation model was developed to evaluate the resilience of tunnel infrastructure, quantified using a functionality metric as a function of loss in traffic capacity and its duration. The model consists of individual modules to account for disruptive events that cause tunnel closures. In this paper, the mechanism and probabilistic models used for each simulation module are presented. A simulation for Eisenhower tunnel, Colorado, was conducted using the proposed method as a validation case study. The results showed that the proposed model could simulate realistic tunnel operation status. While the validation was made for a specific tunnel, the model was designed to be applied to the resilience analysis of any road tunnel with defined design and operation parameters. [ABSTRACT FROM AUTHOR]