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This is an extension of the companion paper (Part 1) that presents the details of the two buildings located in Tokyo and designed using the US Performance Based Seismic Design (PBSD) methodology for one building (US Prototype Building) and the Japanese PBSD methodology for the other (Japan Prototype Building). The paper presents the IDA results and associated discussion on the collapse safety margin and the damage progress of the major structural elements. The Japan Prototype Building made of steel moment-resisting frames equipped with oil dampers is 1.5 times stronger in terms of the collapse safety margin than the US Prototype Building made of an reinforced concrete (RC) core shear wall system. The difference between the two buildings is believed to occur because of the larger redundancy and resultant larger over-strength achieved by the Japan Prototype Building. It is noteworthy that the construction cost of the Japan Prototype Building is about 30% higher than the US Prototype Building as indicated in Part 1. To explain the behavioral difference, sequences, and progresses of damage to major structural members are characterized in reference to the fragility curves of respective members. The benefits of oil dampers are found that the addition of the oil dampers would increase the collapse safety margin by 29% with an extra construction cost of 3%. [ABSTRACT FROM AUTHOR]

The concept of performance-based seismic design dates from the 1990s. Several complex bridges in seismic hazard zones were designed following this concept. The list includes but not limited to the New Carquinez Suspension Bridge, the New Tacoma Narrows Suspension Bridge, and the Gerald Desmond Bridge. This paper documents the fundamental issues that were considered in the seismic design of recent cable-supported bridges including the seismic performance-based criteria (PBDC). The paper also discusses how the local damage levels are employed through a deformation-based approach to achieve the global performance objectives of the bridge. The paper also explains the development procedure of spectrum compatible ground motions through probabilistic seismic hazard analysis. Issues such as foundation modeling, soil–structure interaction, and appropriate damping are also outlined. PBDC is an appropriate approach for the seismic assessment of this class of bridges, particularly if the damage is determined using a displacement-based assessment approach. [ABSTRACT FROM AUTHOR]

Summary: In the United States, wood has been traditionally used in residential construction. However, the combustibility of wood still limits its use as a building material in prescriptive building codes, and to overcome the limitations, performance‐based codes can be used. In order to properly analyze performance‐based designs, more information on the fire performance of materials is required, including fire performance under different fire exposures. The char rate when timber elements are exposed to the standard time‐temperature curve have been well characterized and can be used to determine the fire‐resistance rating. However, much less is known about the rate of char formation under other fire exposures and time‐temperature curves. In this study, we used time‐temperature data from full‐scale compartment fire tests and applied that data in an intermediate‐scale horizontal furnace. By measuring the furnace temperature, fuel consumption, and heat flux during the various tests, we identified that the furnace could closely replicate the shape of a real time‐temperature fire curve from a ventilation controlled compartment. However, the furnace fell short in terms of meeting the peak temperatures at flashover and heat fluxes expected in a real compartment fire. [ABSTRACT FROM AUTHOR]

Simplified performance-based liquefaction triggering procedures have sought to address observed inconsistencies in predicted liquefaction triggering hazards across the United States resulting from conventional, pseudoprobabilistic analysis procedures. Unfortunately, current simplified performance-based procedures are limited to use with a single liquefaction triggering curve. This paper introduces a modified performance-based procedure and applies it to a different liquefaction triggering curve that is currently used by many engineering practitioners. The modified procedure is derived, and the concept of liquefaction loading parameter maps is introduced. Validation of the modified procedure against the full performance-based procedure is performed for multiple U.S. cities and soil profiles at three different return periods. The results of the validation demonstrate that the modified performance-based procedure reasonably approximates the full performance-based procedure across multiple return periods, though it tends to slightly underpredict the full performance-based results on average. Some discussion regarding the limitations and potential benefits of this modified procedure is provided. [ABSTRACT FROM AUTHOR]

Current research trends in residential construction focus on the development of performance-based design methodologies for wood structures. As one key prerequisite to the implementation of such design concept, the performance objectives and their corresponding limit state criteria must be properly defined first. So far, the displacement-based limit state criterion, such as the one proposed in ASCE 41, is the only type of standard available for wood structures. In this paper, damage index-based limit state criterion is proposed for wood-frame buildings. The Park-Ang damage model is used to estimate damage to the wood structures caused by seismic loads. An incremental dynamic analysis-based approach is developed to calibrate the damage model parameter for wood shear wall. To predict the potential damage of wood-frame buildings under future earthquakes, the relationship between calculated damage index and observed building damage is established and validated by experimental test data. The results of this research show that displacement alone may not be a reliable indicator for seismic performance of wood structures and damage index-based criterion allows a more realistic performance evaluation. [ABSTRACT FROM AUTHOR]

Environmental design has a long history of concern for ecosystems but has often lacked explicit assessments of, or goals associated with, site performance. Ecosystem services provide an organizing concept around which to make a wide array of environmental and, to some extent, social design goals explicit. Additionally, they allow assessment and evaluation of site-design decisions through both pre-construction modeling and/or post-occupancy evaluation. The U.S. Green Building Council's Leadership in Energy and Environmental Design (LEED) rating system and the Sustainable Sites Initiative (SITES) are used as examples of how performance-based site design can be incorporated into the design process. We suggest that the maintenance of ecosystem services become a standard and increasingly monitored goal for the practice of environmental design. This move toward performance goals linked to ecosystem services for which success or failure can be determined is essential if environmental design is to offer a substantive contribution to the achievement of a more sustainable culture. [ABSTRACT FROM AUTHOR]

Abstract: This paper presents a fragility assessment for roof sheathing in light frame constructions built in high wind regions. A fragility methodology is developed to assess the performance of roof sheathing subjected to uplift (suction) pressures. The majority of single-family housing in the United States is woodframe construction. A review of the performance of woodframe buildings after recent hurricanes has shown that the majority of wind damage (insured losses) was the result of a breach in the building envelope. Loss of roof sheathing and broken windows result in water penetration causing extensive interior damage and associated property and contents losses. The aim of this study was to develop a fragility model for roof sheathing uplift using available fastener test data, recently developed wind load statistics, and a code-based approach for evaluating pressures. Five baseline structures considering different roof shapes, geographic locations, nail types, and enclosure conditions were investigated using simulation and system reliability concepts. Fragilities and complementary fragilities (or survivorship curves) of roof sheathing removal considering different levels of damage are developed as a function of basic wind speed (3 s gust wind speed at 33 ft (10 m) above the ground in open terrain). The fragility models presented in this paper can be used to develop performance-based design guidelines for woodframe structures as well as tools for condition assessment and loss estimation for use with the existing building inventory. [Copyright &y& Elsevier]