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Tecnológico Superior Corporativo Edwards Deming – January - June Vol. 8 - 1 - 2024 https://revista-edwardsdeming.com/index.php/es
e-ISSN: 2576-0971
Another research is the one carried out by Paz (2014), focused on the calculation
procedure for the elaboration of seismic spectra for the seismic-resistant design of
structures, in which seismic spectra are considered important as a tool for analysis and
design of structures, minimum properties are described for dynamic analysis such as:
mass, damping, stiffness; from this, the vibration theory of a particle is determined
through the generation of spectra; where, starting from seismic readings , it considers
free motion as the simplest for the analysis of a moving particle. In addition, linear
systems are analyzed which obey Hooke's Law, therefore, only small deformations are
considered and the response of the particle or a single system with a single degree of
freedom to a seismic record (accelerogram) is obtained, the graphs obtained represent
maximum responses for different systems, this response spectrum uses a design
spectrum suitable for elastic design, inelastic aspects of the systems are also analyzed,
where nonlinear effects are considered to obtain a more realistic design. (Paz, 2014).
The seismic hazard study in Ecuador is still under development, new seismogenic zones
have not been defined and active faults have not been modeled, nor has an attenuation
study of accelerations, velocities, displacements and seismic intensities been performed,
considering the existing anisotropy and heterogeneities, in addition to the determination
of seismic recurrence with the new seismogenic sources defined and the updated
hypocenter catalogs (Hidalgo, 2011). (Hidalgo, 2011)..
Under this context and considering that many times small earthquakes are forgotten due
to the little information available and often there are only testimonies from populated
areas, causing the epicenters to be poorly located, this information has not been well
received by researchers and often discarded to take as valid only that based on
instrumentation, the lack of information over time makes it important to study the
microtremors and the need to instrument them more often and compare these data
over time is born.
During the history of the city of Riobamba, it has been affected by some earthquakes of
great intensity, thus in the year 1645 the city was known as a Villa that according to data
from 1605 was defined as "four streets both lengthwise and widthwise with a central
square..., whose buildings were made of adobe and thatched roofs and about three or
four tile roofs...."According to testimonies, reference is made to the fact that the
buildings were built on bad soil, which led to an amplification of seismic waves, according
to the data provided by the Geophysical Institute of the National Polytechnic School,
the epicenter was located at coordinates -1.68S and -78.55W very close to the village,
being felt in Quito with countless aftershocks produced several deaths. According to
historical archives and considering the type of houses built at the time, this earthquake
can be classified as grade VI on the modified Mercalli scale (Barahona and Mora, 2013).
In 1968, an earthquake qualified by history as a "dreadful cataclysm" in the central zone
of the Ecuadorian highlands, according to reports of the date, the terrible soil on which
the city was built and the poor quality of materials with which the houses of the time