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• Tension tests of glued-in steel rods embedded in mass-ply panels are reported. • A two-step adhesive application process for glued-in steel rods is tested. • Monotonic and cyclic testing show no significant difference in tension capacity. • Elastic stiffness does not change with embedment depth under monotonic loads. • Further testing is required for conclusions on elastic stiffness under cyclic loads. The length of mass timber wall panels is a limiting factor in designing taller buildings. Splice designs are needed to maintain panel transportability while transferring shear and moment forces from higher floors to the foundation under lateral loading. One such splice design utilizes structural adhesive to glue threaded steel rods into the ends of wall panels being connected. This paper reports tests of the tension capacity of glued-in rods embedded in Mass Ply Panels (MPP). Twenty glued-in rods were tested under monotonic and cyclic protocols. Embedment depths ranged between 304.8 mm (12 in.) and 812.8 mm (32 in.). Load and displacement were measured during tests to report values per ISO 6891 and an international code council acceptance criteria document. Elastic stiffness, peak capacity, design capacity, and a predictive capacity equation were determined. Results showed a similar stiffness for all embedment depths and a negligible difference between peak capacities from monotonic and cyclic testing. While the data reported is only directly applicable for analysis of the specific MPP and epoxy combination used in the test program, the methodology herein can be utilized for future testing of timber-adhesive glued-in rods. [ABSTRACT FROM AUTHOR]

• A 1:6 laboratory model of an elevated building was tested to collapse under surge and wave loading. • System identification is used to quantify out-of-water and in-water frequencies and damping. • Lidar point clouds were used to quantify damage following hydrodynamic testing. • OpenFOAM and OpenSees coupled simulations captured experimental acceleration responses. • Finite element model updating provides insights on parameters influencing structural response. An experimental program of a 1:6 scale elevated wood frame shear-wall residential building was developed to model the damage progression of buildings subjected to increasing hurricane surge depth and wave conditions until collapse. This paper presents testing and system identification methods used to characterize structural engineering properties of the physical model that accumulated damage during hydrodynamic testing under increasing surge depth and wave heights. Methods used include (a) quasi-static lateral load-deformation testing, (b) out-of-water dynamic structural characterization testing under free vibration, ambient vibration, and forced vibration, conducted on the test specimen prior to hydrodynamic testing, (c) in-water dynamic structural characterization during hydrodynamic testing, (d) quantification of accumulated damage in hydrodynamic testing through observed changes in the laser scan point cloud data of the specimen, and (e) finite element model updating. The accumulated damage in the test specimen is correlated to changes in modal features (frequency, damping, and mode shapes) assessed using two output-only system identification (SID) methods. In addition, finite volume numerical models are used to determine detailed pressure distributions on the test specimen which are coupled with finite element (FE) models that are updated, in a phased manner, to understand the contribution of structural and nonstructural components on the modeled stiffness and strength of the physical model. Lastly, the impact of the damage on the modal features of the physical model of the building and their sensitivity to FE model assumptions are presented. [ABSTRACT FROM AUTHOR]

Abstract Cross-laminated timber (CLT) is becoming increasingly adopted into North American construction, yet little is known about the impacts of environmental exposure (e.g., to rain during construction) on its long-term performance. The lack of protocols for on-site moisture protection in North America makes it a pressing matter to determine general moisture responses of this material in order to establish a behavioral baseline for practitioners and future researchers. A CLT floor panel sample was exposed to cycles of wetting and drying in an environmental chamber. During these cycles, physical and geometrical properties of the panel were monitored. Testing results indicate that discontinuities in the layup CLT affects the hygroscopic behavior of the product. While the panel showed high dimensional stability, it also exhibited checking, cupping, and interfacial shearing after cycling. Bending test results before and after cycling indicated a reduction of the structural capacity due to the weathering. Highlights • Gaps in the surface, in conjunction with wane, created a matrix of openings for ingress. • Moisture can remain or continue to accumulate at the core, even during drying conditions. • Checking, cupping and inter-facial shearing were pronounced, especially at edges. • A reduction of the structural capacity was observed in the weathered samples. • MC sampling should account for high spatial variability and acute sensor sensitivity. [ABSTRACT FROM AUTHOR]

The role of ground motion duration on the seismic performance of building structures remains unclear. This paper presents results on the effects of ground motion duration on the seismic behaviour of a 3-D plan-asymmetric reinforced concrete building. A three-story reinforced concrete building tested in Europe is used as a case study. A nonlinear model of the building with fibre-section distributed inelasticity displacement-based beam-column elements is subjected to two ground motion sets: (1) long-duration bi-directional earthquake ground motions, and (2) short-duration bi-directional earthquake ground motions. A new ground motion selection procedure is proposed to isolate the effect of duration on the structural response and on damage assessment. For comparative studies, long- and short-duration ground motions are selected so that they have similar response spectra. The damage assessment is performed analysing global and local responses. Global responses of the structure are evaluated in terms of peak roof drift ratios, peak interstory drift ratios (IDRs), IDR envelopes, normalized roof displacements relative to motion of the centre of gravity of the roof, and dissipated energy. Local responses assessed include moment-curvature or moment-rotation response in beams and columns as well as the hysteretic energy dissipated at selected sections of the structure. Two damage indices available in the literature are used to characterize the level of damage that the structure experiences, through damage index-based fragility curves that are developed as part of the work. For the short-duration motions, fragility curves developed independently from interstory responses and from the damage indices are similar, thus providing confidence into the use of the damages indices for fragility curve development. In addition, results indicate that for the vintage plan-asymmetric building analysed, the ground motion duration plays a role in the damage predicted using the two damage indices. [ABSTRACT FROM AUTHOR]

This study establishes a general methodology to account for the effects of the amount of disaster debris generated, debris dispersal, the duration floodwater pooling for events like tsunamis, and damage to infrastructure on initial and time evolution of connectivity between critical facilities and key locations within a community such as evacuation zones and shelters. The proposed methodology is applied to Seaside, OR, for cascading seismic and tsunami hazards corresponding to seven return periods ranging from 250 to 10,000 years. The post-event connectivity is assessed for the first 72 h. The results provide insights on immediate post-event connectivity, its evolution with time as floodwaters recede and as the debris is cleared, and the relative effect of debris, floodwater pooling, and infrastructure damage on connectivity. For example, the level of disconnection caused by debris and flooding in Seaside is not always directly proportional to the return period (magnitude) of the seismic-tsunami event. Results show that bridge damage further exacerbates the lack of connectivity due to debris and floodwater pooling, highlighting that multi-hazard and multi-infrastructure analyses are necessary to understand connectivity for disasters. [ABSTRACT FROM AUTHOR]

• Twenty in-plane shear tests on CLT surface spline connections were performed. • Splines were constructed using nails and three different screw spacings. • Nail spline connections were more ductile than the screw connections. • An engineering performance model for the CLT splines is presented. Cross-laminated timber (CLT) panels have been used as structural diaphragm elements that form the primary lateral force-resisting system in mass-timber buildings. To better understand the overall performance of CLT diaphragms, an experimental program including monotonic and cyclic in-plane shear panel-to-panel spline connections tests was conducted. The spline connections were constructed using nails and screws with different spacings. Experimental results from the testing program allow for characterization of the performance of the connection systems in terms of elastic stiffness, strength, and ductility. Based on the results of this specific testing program, nailed spline connections displayed similar performance in terms of stiffness and strength and were more 58.7% more ductile than the screw connections, which is partly explained by the larger overstrength factors observed for the screw connections. A simplified performance model is presented to aid designers in determining the elastic, inelastic, and post-peak force parameters of the various spline connections tested. [ABSTRACT FROM AUTHOR]

Abstract This study presents a probabilistic seismic and tsunami damage analysis (PSTDA) due to both earthquake shaking and tsunami inundation from tsunamigenic earthquake events at a coastal community. In particular, this study evaluates the annual exceedance probability (AEP) of seismic and tsunami hazards through earthquake and tsunami modeling that share the same fault sources. Then, estimates of earthquake and tsunami impact on the built environment utilizing fragility functions is predicted spatially. The PSTDA evaluates the combined impacts of earthquake and tsunami through a stochastic approach that accounts for the accumulated damage due to seismic shaking and subsequent tsunami inundation. A case study is setup and applied to Seaside, Oregon, for tsunamigenic earthquake events originating from the Cascadia Subduction Zone (CSZ) in order to illustrate the application of the PSTDA evaluation framework. The PSTDA integrates as a step within a resilience-focused risk-informed decision making process, which includes the assessment of direct and indirect socio-economic losses due to tsunamigenic earthquake events. [ABSTRACT FROM AUTHOR]

Annual exceedance probabilities of the maximum tsunami inundation depth, hMax, and momentum flux, MMax, conditional on a full-rupture event of the Cascadia Subduction Zone (CSZ) were used to estimate the probability of building damage using a fragility analysis at Seaside, Oregon. Tax lot data, Google Street View, and field reconnaissance surveys were used to classify the buildings in Seaside and to correlate building typologies with existing fragility curves according to the construction material, number of stories, and building seismic design level based on the date of construction. A fragility analysis was used to estimate the damage probability of buildings for 500-, 1000-, and 2500-year exceedance probabilities conditioned on a full-rupture CSZ event. Finally, the sensitivity of building damage was estimated for both the aleatory and epistemic uncertainties involved in the process of damage estimation. Probable damage estimates from the fragility curves based on hMax and on MMax both generally show higher damage probability for structures that are wooden and closer to the shoreline than those that are reinforced concrete (RC) and further landward of the shoreline. However, a relatively high and somewhat unrealistic damage probability was found at the river and creek region from the fragility curve analysis using hMax. Within 500 m from the shoreline, wood structure damage shows significant sensitivity to the aleatory uncertainty of the tsunami generation from the CSZ event. On the other hand, RC structure damage showed equal sensitivity to the aleatory uncertainty of the tsunami generation as well as the epistemic uncertainties due to the numerical modeling of the tsunami inundation (friction), the building classification (material and date of construction), and the type of fragility curves (depth or momentum flux type curves). Further from the shoreline, the wood structures showed similar aleatory and epistemic uncertainties, qualitatively similar to the RC structure sensitivity closer to the shoreline. [ABSTRACT FROM AUTHOR]

• A framework for post-earthquake response assessment of Pagoda temples is developed and outlined. • Lidar data are used for post-earthquake geometry and damage (crack) quantification. • Dynamic characterization tests informed the computational model development. • The Applied Element Method is compared to the Finite Element Method for a historic masonry pagoda style temple. This paper presents a linear applied element method (AEM) modeling approach for investigating the effects of the Mw 7.8 2015 Gorkha Nepal earthquake on a historical Pagoda temple. The impact of the earthquake is also investigated using linear FEM models and the results from both modeling approaches are compared. The numerical models are developed and calibrated using pre- and post-earthquake data collected from ambient vibration testing, lidar scans and data processing, and visual damage assessment. The numerical results indicate that the linear AEM models are as reliable as the finite element method (FEM) models to predict the modal response of the case study temple. In addition, the AEM models can potentially be further developed to estimate the damage from future earthquakes through nonlinear analyses. The present study not only informs the present health status of the masonry temple, but it also estimates how acceleration at the base of the temple is propagated through the height of the temple through comparison of floor response spectra, which could provide valuable insights into the force distribution over the height of the temple for the design of future retrofits. [ABSTRACT FROM AUTHOR]

• Decision support framework for quantifying and improving infrastructure resilience. • Framework considers multiple hazards and interdependence between infrastructure. • Framework also includes decision support options and community expectations. • Resilience = P (robustenss ∩ rapidity) and is quantified using a Bayesian network. • Framework is applied to Seaside, Oregon, for seismic ground shaking and tsunami hazards. A probabilistic decision support framework is developed in this study for community resilience planning under multiple hazards using performance goals based guidelines such as the Oregon Resilience Plan and the National Institute of Standards and Technology Community Resilience Planning Guide. Herein, resilience of community infrastructure systems is defined as the joint probability of achieving robustness and rapidity based performance goals, which is quantified using Bayesian networks. The framework assesses the effects of decision support options such as selection of hazards, resilience goals, and mitigation (ex-ante) and response (ex-post) strategies to identify measures that can improve infrastructure performance to meet community defined resilience goals. This framework is applied for resilience assessment of building, transportation, water, and electric power infrastructure systems in Seaside, Oregon, under combined earthquake ground shaking and tsunami inundation hazards corresponding to different return periods. Uncertainties in damage, restoration, and economic losses are explicitly considered and propagated in the framework using Monte Carlo simulation (MCS). The MCS results are then used to inform the Bayesian network, which evaluates the joint resilience of infrastructure systems in Seaside. Results highlight the impact of considering different performance goals, introduction of ex-ante and ex-post measures, and interdependencies between various infrastructure systems on infrastructure resilience. [ABSTRACT FROM AUTHOR]

Highlights • First shake table test of platform-style CLT construction with continuous hold down rods. • Provides an opportunity assess stacked CLGT shear wall performance. • Quantify the behavior of nailed angle connectors on CLT stacked shear wall dynamic performance. • Assess the effect of transverse walls on CLT shear wall performance. Abstract Cross-laminated timber (CLT) manufacturing and construction has been steadily growing since its inception in Europe in the 1990s. In the US, the growth of the CLT adoption is inhibited by the lack of codified design provisions for CLT in high seismic regions. This led to a multi-year study conducted by Colorado State University to investigate suitable seismic design parameters of CLT shear wall systems. This paper presents the results from a series of shake-table tests featuring a full-scale two-story mass-timber building utilizing CLT Seismic Force Resisting Systems (SFRS). The building was designed using an R- factor equal to 4.0 under the equivalent lateral force procedure specifications of the ASCE 7-16 Standard. The test program included three phases with different wall configurations, reflecting different wall panel aspect ratios and the existence of transverse CLT walls. Test results indicate that the code-level life safety objective was achieved in all test configurations. The addition of transverse walls did not affect the ability of the panels to rock, and improved the performance of the building structural system. [ABSTRACT FROM AUTHOR]

Tsunamis are rare destructive phenomena caused by the sudden displacement of a large amount of water in the ocean and can result in enormous losses to coastal communities. The resilience of coastal communities to tsunamis can be improved through the use of risk-informed decision making tools. Performance-Based Engineering (PBE) approaches have been developed for different natural hazards including earthquake, fire, hurricane, and wind to perform probabilistic risk assessment for structures. In this study, a probabilistic Performance-Based Tsunami Engineering (PBTE) framework based on the total probability theorem is proposed for the risk assessment of structures subject to tsunamis. The proposed framework can be disaggregated into the different basic analysis phases of hazard analysis, foundation and structure characterization, interaction analysis, structural analysis, damage analysis, and loss analysis. An application example consisting of the risk assessment of a three-story steel moment frame structure was performed using the proposed framework. The probability of exceedance of the total replacement cost including structural, nonstructural, and content losses were computed. [ABSTRACT FROM AUTHOR]