Seismic response of long-period sites: lessons from the September 19, 1985, Mexican earthquake

The implications for seismic design in Canada, of the acceleration data recorded at a number of sites in Mexico City during the September 19, 1985, earthquake, were investigated. The conditions for amplification of low-level incoming ground motions at deep sites were identified, in particular, the critical role of variation in shear modulus with shear strain. The current procedure for determining site-specific ground motions was evaluated and major sources of uncertainty in the results were identified. Criteria for selecting representative input motions for site response studies are recommended based on results of analyses of Mexico City sites. A comparative study of sites in the Fraser Delta area of British Columbia showed that offshore subduction earthquakes should be considered when developing design spectra for deep sites in the delta. Key words: earthquakes, seismic design, ground motions, shear modulus, design spectra.

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Insights and challenges associated with determining seismic design forces in a loading code

Bulletin of the New Zealand Society for Earthquake Engineering ◽

10.5459/bnzsee.28.3.224-246 ◽

1995 ◽

Vol 28 (3) ◽

pp. 224-246 ◽

Cited By ~ 9

Author(s):

A. C. Heidebrecht

Keyword(s):

New Zealand ◽

Seismic Hazard ◽

Seismic Design ◽

Ground Motions ◽

Performance Expectations ◽

Hazard Parameters ◽

Seismic Hazard Parameters ◽

Frequent Reference

This paper presents and discusses a number of important topics which affect the determination of seismic design forces in a loading code. These range broadly from seismic hazard through to design philosophy and include the following aspects: influence of uncertainty in determining seismic hazard, seismic hazard parameters, site effects, probability level of design ground motions, role of deformations in seismic design, performance expectations and level of protection. The discussion makes frequent reference to the seismic provisions of both the National Building Code of Canada (1995) and the New Zealand Loading Standard (1992). Also, comparisons are made of seismic hazard and seismic design forces for several Canadian and New Zealand cities.

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Amplification of Strong Ground Motions at Heathcote Valley during the 2010–2011 Canterbury Earthquakes: The Role of 2D Nonlinear Site Response

Bulletin of the Seismological Society of America ◽

10.1785/0120160389 ◽

2017 ◽

Vol 107 (5) ◽

pp. 2117-2130 ◽

Cited By ~ 6

Author(s):

Seokho Jeong ◽

Brendon A. Bradley

Keyword(s):

Site Response ◽

Ground Motions ◽

Strong Ground Motions ◽

Nonlinear Site Response ◽

Strong Ground

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Preliminary Design of Low-Rise Buildings Stiffened with Buckling-Restrained Braces by a Displacement-Based Approach

Earthquake Spectra ◽

10.1193/1.3054638 ◽

2009 ◽

Vol 25 (1) ◽

pp. 185-211 ◽

Cited By ~ 18

Author(s):

Amador Teran-Gilmore ◽

Neftali Virto-Cambray

Keyword(s):

Mexico City ◽

Seismic Design ◽

Mechanical Characteristics ◽

Ground Motions ◽

Flexural Behavior ◽

Preliminary Design ◽

Lake Zone ◽

Buckling Restrained Braces ◽

Displacement Based ◽

Story Building

A displacement-based methodology for the preliminary design of a system of buckling-restrained braces is introduced. The methodology applies to the case of low-rise buildings, whose dynamic response is not significantly influenced by global flexural behavior or higher modes. The methodology is applied to the preliminary design of a five-story building located in the Lake Zone of Mexico City. From the evaluation of the global mechanical characteristics of the building and of its seismic performance when subjected to ground motions generated in that zone, it is concluded that the proposed methodology yields an adequate level of seismic design.

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Introduction

Enlightened Immunity ◽

10.11126/stanford/9781503604339.003.0001 ◽

2018 ◽

pp. 1-22 ◽

Cited By ~ 1

Author(s):

Paul Ramírez

Keyword(s):

Mexico City ◽

New Spain ◽

Healthcare Reform ◽

Critical Role ◽

Colonial Mexico ◽

Rural Regions ◽

Corporate Sponsors ◽

French Physician ◽

Critical Moments

The introduction recounts the experiences of French physician Esteban Morel, who arrived in Mexico City in 1778 and immediately set about introducing inoculation among the upper classes during an epidemic of smallpox. Reluctant parents and rampant rumors of deformity and death stymied the inoculation campaign that year and suggest the critical role of nonprofessionals in colonial Mexico in healthcare reform. In an age when European monarchs looked to govern from above the health of populations, the perspectives and sensibilities of laypeople in the socially heterogeneous barrios, subdistricts, and rural regions of New Spain remained pivotal. Experiments with disease and its control were critical moments in which amateur scientists, physicians, corporate sponsors, and lay communities came together to assess the merits of reform and the relevance of Atlantic practices and projects for their own lives.

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The Role of the SLP in Autism Spectrum Disorder Screening and Assessment

Perspectives on Language Learning and Education ◽

10.1044/lle15.2.50 ◽

2008 ◽

Vol 15 (2) ◽

pp. 50-59 ◽

Cited By ~ 1

Author(s):

Amy Philofsky

Keyword(s):

Language Development ◽

Critical Role ◽

Children With Autism ◽

Autism Spectrum ◽

Children With Asd ◽

Prevalence Estimates ◽

Notable Increase ◽

Screening Assessment ◽

Critical Components

AbstractRecent prevalence estimates for autism have been alarming as a function of the notable increase. Speech-language pathologists play a critical role in screening, assessment and intervention for children with autism. This article reviews signs that may be indicative of autism at different stages of language development, and discusses the importance of several psychometric properties—sensitivity and specificity—in utilizing screening measures for children with autism. Critical components of assessment for children with autism are reviewed. This article concludes with examples of intervention targets for children with ASD at various levels of language development.

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