Seismic reinforcement: how it works and why it is so important
This article is also available here in Spanish.

Seismic reinforcement: how it works and why it is so important

My list

Author | Jaime Ramos

The Earth, as rocky planet that it is, is alive beneath our feet. Although the geological activity cannot be felt, sometimes it manifests in an abrupt and dangerous fashion. Earthquakes and seismic events are responsible for transmitting those tectonic beats and have forced humans to be prepared.

Depending on the particular magnitude of the earthquakes, according to the Richter scale, each year there are between one and two dozen earthquakes exceeding a magnitude of eight, up to more than 2,000.

How can buildings be adapted and reinforced to withstand earthquakes

The risk increases in more vulnerable areas or geological points. Earthquakes pose a threat because many regions have high density populations. Cities such as Manila, Jakarta, Los Angeles, San Francisco, Lima, Tehran, Istanbul (https://tomorrow.city/a/success-story-urban-regeneration-in-the-municipality-of-gaziosmanpasa-after-the-earthquake-in-1999) or Tokyo have significant seismic activity, although this is not always felt on the ground in these areas.

The Japanese capital, for example, is located in an area in which 80% of the planet’s largest earthquakes occur. The University of Tokyo estimates that the city has a 98% chance of suffering a major earthquake within the next 30 years.

seismic retrofitting 129

These are the main areas in which earthquake engineering has been developed as an essential instrument of urban protection through architecture. In recent decades, a methodology known as Performance Based Earthquake Engineering has been developed to identify the response of anti-seismic technologies.

What is seismic reinforcement

Seismic retrofitting is an application of earthquake engineering that modifies internal and external structures of buildings using specific methods. The aim is to develop an architecture that offers greater resistance in the event of geological disasters.

Anti-seismic reinforcement methods

To achieve this, there are numerous methods at a global level. They tend to be based on three protection functionalities: through dissipation, resistance and through deformation or ductility.

Energy dissipation

Anti-seismic reinforcement methods through dissipation, are designed to channel or absorb an earthquake’s energy to prevent it from impacting the health of the building and from being offloaded in the form of heat or movement. They tend to be effective for what is known as seismic resonance that lingers after the initial moments of an earthquake.

seismic retrofitting 130

A derivative and global reference of this method can be found in the Taipei 101 skyscraper in Taiwan. A 728-ton golden sphere works as a TMD (tuned mass damper), maintaining the equilibrium of the 508-meter building in the event of potential seismic events.

Seismic resistance

These are structures that increase resistance to the impact of an earthquake. Among the different methods are external post-tensioned metal straps that use precast concrete or the more conspicuous retrofitting on the building itself, in the form or massive columns or structures.

This method is normally used on historical or older buildings that do not allow major internal refurbishments. The Rostrevor House in Wellington, New Zealand uses this method to alleviate the effect of the 30,000 earthquakes of all magnitudes that the country experiences in each year.

Ductility to withstand earthquakes

Ductility control methods recognize that an earthquake will damage a building. The angular stone directs the energy towards structural elements that can absorb that energy and deform without affecting the rest of the building or run the risk of collapsing.

The 73 floors of the Wilshire Grand Center building in Los Angeles (United States) protect the building’s equilibrium thanks to shape memory alloys (SMA). In the event of an earthquake, they absorb part of the energy and deform, to then return to their prior state.

The development of these methods, enable the harmful effects of disasters to be mitigated in cities. They form an essential part of the new urban design that all smart cities should incorporate in order to guarantee the safety of the new urban landscape.

Images | iStock/Skarie20, iStock/TokioMarineLife, Someformofhuman

Related content

Recommended profiles for you

AA
ANA ABRAHIM
Fundação Municipal de Cultura, Turismo e Eventos
Director of Cultural Policies
CO
Crina Oltean-Dumbrava
University of Bradford
Professor in Sustainable Built Environment
AB
Ali Bagabas
Saudi Aramco
a project manager for smart city related projects at an IT department
PC
Pedro Cortes
Pedro Cortes
Founder
VR
Vinod Rathi
Crescendo Transcription Private Limited
Director
ML
Mihkel Lehtmets
EyeVi Technologies
Chief Marketing Officer
OZ
Oscar Zarate
Inteligencia urbana
Director de gestión urbana
ID
Isabel Delgado
Instituto metropolitano de patrimonio
Asistente de Diseño e investigación
SI
Suhairah Amaliyah Ira
Student
I am a student
CT
Chiva Thlang
Palladium 3i
Infrastructure Policy Manager
ML
Maria Andree Lopez Gomez
MUN
postdoctoral fellow
SB
Susan Bwowe
M.Sc Student - Mundus Urbano
Project Cost Manager
UT
Ulari Teder
EyeVi Technologies Ltd
Sales Director
IS
Imrandeep Singh
RODIC Consultants Pvt ltd
Support Engineer
IS
Ibarra Sudario
SUDACON Inc.
Manager
PC
PHILLIPE COSTA
Federal University of Rio de Janeiro
Researcher, PhD Student, Professor
MX
Maximilian Xavier
FIDELIDADE
MP
Marcela Pérez
Congéneres tic
Directora
LP
Luis Enrique Pérez Chacón
Pérez & Carballo Arquitectos
BIM SPECIALIST
AG
Angela Maria Galarza
AGArquitectura
Creator, CEO