The International Platform for Reducing Earthquake Disaster (IPRED) supports the development and transmission of seismology and earthquake engineering knowledge and provides methodologies for governments and local communities to lead their own efforts in mitigating earthquake disasters.
Last update: 31 January 2024Every year, natural hazards affect more than 200 million people, and the risks are increasing, especially in developing countries, where a single disaster can set back economic growth by decades. Earthquakes pose considerable risks to livelihoods and the environment, and have a higher mortality rate than other types of natural hazards, with most fatalities occurring due to building collapse.
While it is impossible to prevent an earthquake, disasters can be prevented by reducing the risks associated to earthquakes and minimizing their impacts. The most effective way to prevent earthquake disasters is to design resilient infrastructure and new constructions, while retrofitting existing buildings to strengthen them based on knowledge of the earthquake performance of different building types.
Natural hazards including earthquakes do not recognize geographical borders. Knowledge about earthquakes must be shared for the benefit of all.
Koïchiro Matsuura former Director-General of UNESCOReducing earthquake disaster risk is essential and can be life-saving. Mitigating earthquake disasters requires education, training, and capacity building at all levels. It also calls for a change in mindset, shifting from post-disaster reaction to pre-disaster action. IPRED aims to promote this shift by mobilizing knowledge and technological know-how to support decision-making and strengthen earthquake disaster preparedness and mitigation measures among governments and local communities.
Studying the Earth's movements for disaster reductionThe San Andreas fault, seen here just north of Los Angeles, forms the straight diagonal mountain front bordering the Mojave Desert. Tectonic movement along the fault has been associated with occasional large earthquakes originating near the surface along its path, including a disastrous earthquake in San Francisco in 1906.
IPRED experts have established a network to observe and share new data on the movement of the Earth's surface. When sudden movements occur on a fracture or zone of fractures between two blocks of rock, waves of energy are sent through and along the Earth’s surface, making the ground move, more commonly known as an earthquake. However, accurately studying and predicting ground motion is difficult due to uncertainties in earthquake size, location, and time of occurrence. IPRED experts aim to address this challenge in seismology and earthquake engineering by contributing to realistic and robust modelling proposals for future seismic events.
In addition to studying ground motion, IPRED and UNESCO experts have been examining and creating engineering data on soil-to-structure interaction, as it affects the response of buildings to earthquakes.
Soil to structure interactions includes how much the base of a building moves, how much the building shakes, and how much the floors lean. UNESCO-IPRED, and the International Institute of Seismology and Earthquake Engineering (IISEE) continually study different soil conditions and how they impact different seismic engineering techniques. For example, Natalya Silacheva, an IPRED expert from Kazakhstan, studies seismic microzonation techniques, which enable the subdividing of a potential earthquake-prone area into zones based on their soil properties. The development of these techniques will improve our understanding of how soil properties affect buildings, as well as how an earthquake could lead to other natural hazards such as landslides or flooding.
By preventing buildings from being damaged or collapsing during earthquakes, we can ensure the safety of many people who would otherwise be at risk. Seismic safety aims to prevent casualties and injuries caused by buildings by establishing techniques that minimize damage to constructions. In addition to contributing to standards and codes for large structures, IPRED members also work to strengthen building codes for smaller structures.
To this end, Professor Raúl Alvarez, an IPRED expert from Chile, has identified several building techniques that have worked well through the large magnitude earthquakes experienced by Chile over the last couple of years. Some of these techniques include innovations in dissipating energy from earthquakes so it does not impact the building and seismic base isolation, which is a means of protecting a building against earthquake force by detaching the main structure frame from its bases.
These innovative approaches to seismic safety are then structurally tested using different methods to develop engineering data. Structural testing is a crucial part of the engineering process. It assesses the physical strength of materials and the capacity of existing structures. Through testing, engineers can evaluate the suitability of materials and identify areas for improvement in design and construction.
In addition to assessing physical strength through techniques like hydraulic wall and shaking table tests that measure compressive, shear, and tensile strength, structural testing may also use indirect techniques like x-ray and ultrasound to evaluate quality, ensuring that structures are built to the highest standards.
This data is then used to determine how to improve existing building codes and promote seismic safety to all building actors, including the local population. By improving building codes and promoting seismic safety for all types of constructions, IPRED and IISEE support communities in mitigating the consequences of earthquakes and other natural hazards.
Experience from Chile: seismic safety to save lives during earthquakesIn the past decade, Chile has experienced three major earthquakes. However, due to the country's efficient seismic safety designs, most of its buildings have remained standing, saving many lives.
