Probabilistic performance-based seismic assessment of an existing masonry building

Existing unreinforced masonry (URM) buildings represent a significant part of the constructed facilities. Unfortunately, in case of seismic actions, their structural behavior is negatively affected by the low capacity of masonry components to withstand lateral forces. For this reason, in the past decades, URM buildings have been responsible for fatalities and large economic losses even in the case of moderate earthquakes. This article presents the seismic loss assessment of an old masonry building damaged during the 2014 South Napa earthquake using the framework of the Pacific Earthquake Engineering Research Center’s Performance-Based Earthquake Engineering. For this purpose, the performance is expressed in terms of expected monetary loss curves for different hazard scenarios. Structural and non-structural losses are considered in the analysis using a practical, yet accurate, structural idealization of the URM building, which is validated by the observed damage from the 2014 South Napa earthquake.

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Estimating Downtime from Data on Residential Buildings after the Northridge and Loma Prieta Earthquakes

Earthquake Spectra ◽

10.1193/1.3477993 ◽

2010 ◽

Vol 26 (4) ◽

pp. 951-965 ◽

Cited By ~ 21

Author(s):

Mary C. Comerio ◽

Howard E. Blecher

Keyword(s):

Earthquake Engineering ◽

Residential Buildings ◽

Northridge Earthquake ◽

Engineering Research ◽

Loma Prieta Earthquake ◽

The Pacific ◽

Time Gap ◽

Loma Prieta ◽

Recent Earthquakes ◽

Performance Based Earthquake Engineering

The performance-based earthquake engineering (PBEE) methodology developed by the Pacific Earthquake Engineering Research (PEER) center uses data from recent earthquakes to calibrate its loss models. This paper describes a detailed review of building department permit data from the 1989 Loma Prieta earthquake and the 1994 Northridge earthquake. Although the data is limited to wood-framed residential structures, it provides some insight into the length of time between an event and re-occupancy. Based on a review of approximately 4,900 records, the typical repair of damaged multifamily residential buildings required two years and building replacement required almost four years. When this data is supplemented with additional case studies from other events, the capacity to better calibrate downtime models will improve, particularly if construction-repair times are separated from estimates of the time gap between closure and start-of-repair.

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A New Methodology to Assess Indirect Losses in Bridges Subjected to Multiple Hazards

Emerging Science Journal ◽

10.28991/esj-2018-01159 ◽

2018 ◽

Vol 2 (6) ◽

pp. 400 ◽

Cited By ~ 2

Author(s):

Davide Forcellini

Keyword(s):

Earthquake Engineering ◽

Direct Costs ◽

Engineering Research ◽

Multiple Hazards ◽

The Pacific ◽

Indirect Losses ◽

Performance Based Earthquake Engineering ◽

The Impact ◽

Original Configuration

Decision making approaches to manage bridge recovering after the impact of multiple hazards are increasing all over the world. In particular, bridges can be considered critical links in highway networks because of their vulnerability and their resilience can be assessed on the basis of evaluation of direct and indirect losses. This paper aims at proposing a new methodology to assess indirect losses for bridges subjected to multiple hazards. The method applied to calculate direct costs is the credited Performance Based Earthquake Engineering (PBEE) methodology by the Pacific Earthquake Engineering Research (PEER) center. Therefore, the main objective of the study consists in the assessment of indirect losses that are generally neglected elsewhere. In particular, the paper proposes to calculate indirect losses from direct costs and to divide them into connectivity losses and prolongation of time. The presented formulation has been applied to a real case study aimed at strengthening a benchmark bridge with several isolated configurations. The results show that the application of the proposed methodology allows to evaluate possible solutions to strengthen the original configuration.

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Discussion of “A Framework to Evaluate the Benefit of Seismic Upgrading”

Earthquake Spectra ◽

10.1193/041219eqs086a ◽

2019 ◽

Vol 35 (3) ◽

pp. 1511-1514

Author(s):

Panagiotis Galanis ◽

Marco Broccardo ◽

Lukas Bodenmann ◽

Božidar Stojadinović

Keyword(s):

Earthquake Engineering ◽

Existing Buildings ◽

Seismic Evaluation ◽

Engineering Research ◽

Existing Structures ◽

The Pacific ◽

The One ◽

Performance Based Earthquake Engineering

Discussers (Michel et al.) address the paper “A Framework to Evaluate the Benefit of Seismic Upgrading” written by the coauthors of this response. Discussers present the compliance factor approach to evaluate existing structures and determine the need for a seismic upgrade implemented in the Swiss code SIA 269/8 and compare this approach to the one presented in the discussed paper. The approach proposed in the discussed paper combines elements of the Pacific Earthquake Engineering Research (PEER) Center Performance-Based Earthquake Engineering (PBEE) framework and the standard actuarial frequency-severity approach. Discussers criticize this approach as not being risk based and, consequently, consider it inappropriate for seismic evaluation of existing buildings. Coauthors welcome the comparison of different approaches for evaluation of existing buildings but disagree with the discussers’ characterization of the PEER PBEE framework and, by extension, the approach of the discussed paper.

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Fragility of Hydraulic Elevators for Use in Performance-Based Earthquake Engineering

Earthquake Spectra ◽

10.1193/1.2720902 ◽

2007 ◽

Vol 23 (2) ◽

pp. 459-469 ◽

Cited By ~ 9

Author(s):

Keith Porter

Keyword(s):

Earthquake Engineering ◽

Cumulative Distribution ◽

Nonstructural Components ◽

Engineering Research ◽

Fragility Function ◽

The Pacific ◽

Applied Technology ◽

Binary Regression Analysis ◽

Ground Motion Records ◽

Performance Based Earthquake Engineering

New performance-based earthquake engineering methods developed by the Pacific Earthquake Engineering Research Center, the Applied Technology Council, and others include damage analysis at a highly detailed level, requiring the compilation of fragility functions for a large number of damageable generic structural and nonstructural components. This brief paper presents the development of a fragility function for hydraulic elevators. It uses post-earthquake survey data from 91 elevators in nine California locations after two earthquakes. Surveys were used to collect data on facilities and elevators. Ground-motion records from the California Integrated Seismic Network were used to estimate engineering demands at each site. Binary regression analysis was used to fit a fragility function, which takes the form of a lognormal cumulative distribution function with median value of PGA=0.42 g and logarithmic standard deviation of 0.3. The fragility function appears to be reasonable based on four criteria.

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