Retrofitting of unreinforced masonry structures and considerations for heritage-sensitive constructions

This paper assesses the benefits of a seismic retrofit program for commercial unreinforced masonry structures (CURMs) in Salt Lake County, Utah. A comparative risk assessment embedded in a geographic information systems is the method used. A policy evaluation time horizon of twenty years is set. Future rates of demolition and rehabilitation, with and without a retrofit policy, are assumed. Damage functions for ordinary and retrofitted URMs are used to assess losses having a 10 percent chance of being exceeded over a 50-year exposure period. With a retrofit program, expected losses are reduced by 57 percent or more than a quarter billion dollars when compared to the no-policy scenario. Expected injuries and fatalities are reduced by more than 80 percent. These are minimal benefits expected from enforcement of the seismic provisions of the Uniform Code of Building Conservation.

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Finite/discrete element modelling of reversed cyclic tests on unreinforced masonry structures

Engineering Structures ◽

10.1016/j.engstruct.2017.02.019 ◽

2017 ◽

Vol 138 ◽

pp. 159-169 ◽

Cited By ~ 6

Author(s):

Paola Costanza Miglietta ◽

Evan C. Bentz ◽

Giovanni Grasselli

Keyword(s):

Discrete Element ◽

Unreinforced Masonry ◽

Discrete Element Modelling ◽

Masonry Structures ◽

Cyclic Tests ◽

Element Modelling ◽

Reversed Cyclic

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Testing of Masonry Structures for Seismic Assessment

Earthquake Spectra ◽

10.1193/1.1585872 ◽

1996 ◽

Vol 12 (1) ◽

pp. 145-162 ◽

Cited By ~ 52

Author(s):

G. Michele Calvi ◽

Gregory R. Kingsley ◽

Guido Magenes

Keyword(s):

Energy Dissipation ◽

Experimental Evaluation ◽

Unreinforced Masonry ◽

Seismic Assessment ◽

Experimental Techniques ◽

Masonry Buildings ◽

Masonry Structures ◽

Seismic Loadings ◽

Energy Dissipation Capacity ◽

Reduced Scale

The experimental evaluation of strength, deformability, and energy dissipation capacity of unreinforced masonry buildings subjected to seismic loadings presents unique and complex problems, both for laboratory and field evaluations. The paper addresses these problems, focusing on the relative merits and roles of several experimental techniques, including quasistatic, dynamic, and pseudodynamic loadings at full and reduced scale.

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Development and Calibration of an Earthquake Fatality Function

Earthquake Spectra ◽

10.1193/1.1596916 ◽

2003 ◽

Vol 19 (3) ◽

pp. 605-633 ◽

Cited By ~ 22

Author(s):

John M. Nichols ◽

James E. Beavers

Keyword(s):

United States ◽

Twentieth Century ◽

The United States ◽

Unreinforced Masonry ◽

Earthquake Magnitude ◽

United States Geological Survey ◽

Seismic Events ◽

Calibration Data ◽

Masonry Structures ◽

Remote Locations

Structures present a risk during seismic events from partial or full collapse that can cause death and injury to the occupants. The United States Geological Survey (USGS) has collated data on deaths from and magnitudes of earthquakes. These data have not previously been analyzed to establish any relationships between fatality tolls or fatality rates in different earthquakes. An investigation of the fatality catalogue establishes a bounding function for the twentieth-century fatality data using the USGS assigned earthquake magnitude as the dependent variable. A simple equation was established and calibrated to relate the fatalities in earthquakes having tolls lower than the bounding function to the bounding function. This equation and the calibration data, essentially for unreinforced masonry and timber-framed buildings, provides a procedure for estimating fatality counts in future theoretical events with a specific combination of circumstances. Potential uses of the fatality function with further refinement are economic analysis of seismic mitigation alternatives for unreinforced masonry structures. Current uses of the fatality function can be for real-time estimating of fatalities in earthquakes in remote locations, and estimating fatality counts in future earthquakes for planning purposes.

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