Seismic Evaluation of Low-Rise Reinforced Masonry Buildings with Flexible Diaphragms: II. Analytical Modeling

This and a companion paper compare the results from shaking-table testing, quasi-static testing, and analytical predictions to provide a coherent description of the seismic response of low-rise reinforced masonry buildings with flexible roof diaphragms. This paper presents the development, implementation, and results of coordinated analytical modeling intended to corroborate and extend the results of experimental work discussed in a companion paper, Part I: Seismic and Quasi-Static Testing, and more important, examine the efficacy and accuracy of different analytical modeling approaches. Specifically, linear elastic finite-element models, simplified two-degree-of-freedom models, and nonlinear lumped-parameter models are created and all agree well with measured responses. Based on these, a simple design tool for the analysis of low-rise reinforced masonry buildings with flexible diaphragms is developed and verified.

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Seismic Evaluation of Low-Rise Reinforced Masonry Buildings with Flexible Diaphragms: III. Synthesis and Application

Earthquake Spectra ◽

10.1193/1.2192791 ◽

2006 ◽

Vol 22 (2) ◽

pp. 329-347 ◽

Cited By ~ 3

Author(s):

Gregory L. Cohen ◽

Richard E. Klingner ◽

John R. Hayes ◽

Steven C. Sweeney

Keyword(s):

Earthquake Engineering ◽

Analytical Modeling ◽

Seismic Analysis ◽

Experimental Testing ◽

Evaluation Methodology ◽

Masonry Buildings ◽

Seismic Evaluation ◽

Reinforced Masonry ◽

Shaking Table Testing ◽

Flexible Diaphragms

This paper outlines the last two phases of a joint research study performed by the University of Texas at Austin and the U.S. Army Corp of Engineers, Construction Engineering Research Laboratory, Engineer Research and Development Center (CERL). The study coordinates and synthesizes experimental testing, analytical modeling, practical implementation, and real-world application to enhance FEMA-310, the predominant seismic evaluation methodology for low-rise reinforced masonry buildings with flexible diaphragms. In earlier phases of study, conclusions from shaking-table testing, quasi-static testing, and analytical modeling were used to develop a simple tool for the seismic analysis of these types of buildings. In this paper, the tool is developed in the context of performance-based earthquake engineering into a supplementary evaluation methodology intended to fill a gap in FEMA-310. The tool is applied to four existing buildings and ultimately shown to be simple, useful, and necessary.

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Seismic Evaluation of Low-Rise Reinforced Masonry Buildings with Flexible Diaphragms: I. Seismic and Quasi-Static Testing

Earthquake Spectra ◽

10.1193/1.1776558 ◽

2004 ◽

Vol 20 (3) ◽

pp. 779-801 ◽

Cited By ~ 22

Author(s):

Gregory L. Cohen ◽

Richard E. Klingner ◽

John R. Hayes ◽

Steven C. Sweeney

Keyword(s):

Experimental Testing ◽

Shear Walls ◽

The United States ◽

Companion Paper ◽

Degree Of Freedom ◽

Shaking Table ◽

Masonry Buildings ◽

Static Testing ◽

Reinforced Masonry ◽

Shaking Table Testing

This and a companion paper compare the results from shaking-table testing, quasi-static testing, and analytical predictions, to provide a coherent description of the seismic response of low-rise reinforced masonry buildings with flexible roof diaphragms. Two half-scale, low-rise reinforced masonry buildings with flexible roof diaphragms are subjected to earthquake ground motions on the Tri-axial Earthquake and Shock Simulator at the United States Army Construction Engineering Research Laboratory, Engineer Research and Development Center. Following the shaking-table tests, diaphragms and top four courses of attached masonry walls are salvaged from the half-scale structures and tested quasi-statically in their own plane. In contrast to what is usually assumed in design, the half-scale specimens do not behave as systems with a single degree of freedom associated with the in-plane response of the shear walls, but rather a system with a dominant degree of freedom associated with the in-plane response of the roof diaphragm. A new index describing the potential for diaphragm damage is introduced, the diaphragm drift ratio. A companion paper, Part II: Analytical Modeling, presents analytical work intended to corroborate and extend results from experimental testing.

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Seismic Evaluation of Low-Rise Reinforced Masonry Buildings with Flexible Diaphragms

Masonry ◽

10.1520/stp45710s ◽

2009 ◽

pp. 109-109-38

Author(s):

Gregory L. Cohen ◽

Richard E. Klingner ◽

John R. Hayes ◽

Steven C. Sweeney

Keyword(s):

Masonry Buildings ◽

Seismic Evaluation ◽

Reinforced Masonry ◽

Flexible Diaphragms

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Seismic Evaluation of Low-Rise Reinforced Masonry Buildings with Flexible Diaphragms

Journal of ASTM International ◽

10.1520/jai13661 ◽

2006 ◽

Vol 3 (7) ◽

pp. 13661

Author(s):

GL Cohen ◽

RE Klingner ◽

JR Hayes ◽

SC Sweeney ◽

SW Dean

Keyword(s):

Masonry Buildings ◽

Seismic Evaluation ◽

Reinforced Masonry ◽

Flexible Diaphragms

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Displacement-Based Seismic Assessment of Low-Height Confined Masonry Buildings

Earthquake Spectra ◽

10.1193/1.3111149 ◽

2009 ◽

Vol 25 (2) ◽

pp. 439-464 ◽

Cited By ~ 11

Author(s):

Amador Terán-Gilmore ◽

Oscar Zuñiga-Cuevas ◽

Jorge Ruiz-García

Keyword(s):

Pushover Analysis ◽

Relative Strength ◽

Seismic Assessment ◽

Shaking Table ◽

Evaluation Procedure ◽

Masonry Buildings ◽

Confined Masonry ◽

Shaking Table Testing ◽

Displacement Based ◽

Global And Local

This paper presents a practical displacement-based evaluation procedure for the seismic assessment of low-height regular confined masonry buildings. First, the so-called Coefficient Method established in several FEMA documents is adapted to obtain rapid estimates of inelastic roof displacement demands for regular confined masonry buildings. For that purpose, a statistical study of constant relative strength inelastic displacement ratios of single-degree-of-freedom systems representing confined masonry buildings is carried out. Second, a nonlinear simplified model is introduced to perform pushover analysis of regular confined masonry buildings whose global and local behavior is dominated by shear deformations in the masonry walls. The model, which can be applied through the use of commercial software, can be used to establish the capacity curve of such buildings. Finally, the evaluation procedure is applied to a three-story building tested at a shaking table testing facility.

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Experimental investigation on the seismic performance of masonry buildings using shaking table testing

Bulletin of Earthquake Engineering ◽

10.1007/s10518-012-9410-7 ◽

2012 ◽

Vol 11 (4) ◽

pp. 1157-1190 ◽

Cited By ~ 23

Author(s):

Paulo B. Lourenço ◽

Leonardo Avila ◽

Graça Vasconcelos ◽

J.Pedro Pedro Alves ◽

Nuno Mendes ◽

...

Keyword(s):

Experimental Investigation ◽

Seismic Performance ◽

Shaking Table ◽

Masonry Buildings ◽

Shaking Table Testing

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Analytical Modeling of Zipper Frames Subjected to Shaking Table Testing

Structural Engineering Research Frontiers ◽

10.1061/40944(249)30 ◽

2007 ◽

Author(s):

M. Schachter ◽

A. M. Reinhorn

Keyword(s):

Analytical Modeling ◽

Shaking Table ◽

Shaking Table Testing

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Effects of Scale and Loading Rate with Tests of Concrete and Masonry Structures

Earthquake Spectra ◽

10.1193/1.1585866 ◽

1996 ◽

Vol 12 (1) ◽

pp. 13-28 ◽

Cited By ~ 14

Author(s):

Daniel Abrams

Keyword(s):

Large Scale ◽

Loading Rate ◽

Shaking Table ◽

Masonry Building ◽

Reinforced Concrete Frame ◽

Concrete Frame ◽

Static Testing ◽

Reinforced Masonry ◽

Critical Components ◽

Reduced Scale

Static and dynamic response of large-scale and reduced-scale test structures are correlated to discern effects attributable to scale and loading rate. Three case studies are presented where reduced-scale models were subjected to dynamic excitation using a shaking table. The test structures were: (a) multi-story reinforced masonry building systems, (b) two-story unreinforced masonry bearing and shear wall systems, and (c) ten-story reinforced concrete frame-wall systems. For each study, static testing of either critical components, or of the complete structural system, was done at a large scale to examine differences attributable to the modeling method, or to the loading procedure.

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Performance of masonry structures during the 1994 Northridge (Los Angeles) earthquake

Canadian Journal of Civil Engineering ◽

10.1139/l95-048 ◽

1995 ◽

Vol 22 (2) ◽

pp. 378-402 ◽

Cited By ~ 12

Author(s):

Michel Bruneau

Keyword(s):

Los Angeles ◽

Unreinforced Masonry ◽

Masonry Building ◽

Masonry Buildings ◽

Masonry Structures ◽

Northridge Earthquake ◽

Seismic Evaluation ◽

Masonry Construction ◽

Reinforced Masonry ◽

The Impact

The surface magnitude 6.8 Northridge earthquake which struck the Los Angeles area on January 17, 1994, damaged a large number of engineered buildings, of nearly all construction types. As earthquakes of at least similar strength are expected to occur in most of eastern and western Canada, the study of the effects of this earthquake is of particular significance to Canada. This paper, as part of a concerted multi-paper reporting effort, concentrates on the damage suffered by masonry buildings during this earthquake, and explains why the various types of observed failures occurred. The seismic performance of all masonry construction similar to that commonly found in Canada is reviewed, but a particular emphasis is placed on providing an overview of damage to unreinforced masonry structures which had been rehabilitated before this earthquake. To provide a better appreciation of the impact of this earthquake on masonry buildings, and a better assessment of the engineering significance of their damage in a Canadian perspective, this paper first reviews the evolution of building code requirements for unreinforced masonry buildings up to the seismic retrofit ordinances enacted prior to this earthquake. Examples of various damage types, as observed by the author during his reconnaissance visit to the stricken area, are then presented, along with technically substantiated descriptions of the causes for this damage, and cross-references to relevant clauses from Canadian standards and codes, as well as the recently published Canadian Guidelines for the Seismic Evaluation of Existing Buildings, whenever appropriate. Key words: earthquake, unreinforced masonry, seismic rehabilitation, retrofit, retrofitted masonry building, reinforced masonry, buildings, failure, collapse, heritage buildings.

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