24/06/19 22:25 pm





In January 1986, after assessing the magnitude of the disaster caused by the earthquakes of September 1985, in Mexico City; experts geophysicist and seismic engineer suggested CONACyT (Consejo Nacional de Ciencia y Tecnología) to create basic research and useful technological developments to mitigate the vulnerability of the urban area of the Valley of Mexico, and this way to face this natural hazard.



In 1987 CIRES started the development of the Accelerograph Network for Mexico City (RACM Spanish acronym), with 78 devices, which were donated to the CIRES by the Government Authorities and the Foundation of Civil Engineers Associated.


Distribución de las estaciones de la RACM

In 1997 the CIRES renewed for the first time, with the RAD-851 system, all of the DCA333 accelerometers of the RACM, they were discontinued by the manufacturer in 1995, in this way, it was achieved to keep the service of these devices and the continuity of the registration of earthquakes that occasionally could affect the Mexico Valley.

It is noteworthy that the CENAPRED (Centro Nacional de Prevención de Desastres) supported in the modernization of the equipment donated by FICA through trust 2038 of the Mexican Seismic Network, sponsored by the Federal Government in the lapse from 2006 to 2011..



From 2011 to 2012, as part of a new agreement with the SOS (Secretaría de Obras y Servicios) of the Mexico City government authorities, CIRES regained the civil work of all stations of the RACM and renewed again its accelerometers with the new RAD-12/16 system. Also this technological development implemented technical progress, such as increasing their equipments of 12 to 16 bits resolution, as well as in their monitoring systems and remote interrogation.

The network currently has 80 accelerometers, 72 of surface and 8 of borehole. Which are distributed in the following way: 66 accelerometric stations of register in surface, 6 accelerometers installed in two structures and 8 sensors for subsurface monitoring. The site of installation, in the Valley of Mexico, was selected in 1987, according to experts in soil mechanics and earthquake engineering judgment.

These accelerometers record the information on a PCMCIA card with capacity to store 34 minutes of information. They have adjustable pre-event memory to record up to 56 seconds before the earthquake and post-event up to 64 seconds after the moment of the earthquake acceleration is less than the selected trigger level.

To get in the site the registered accelerograms, it is use a portable computer, which is inspected and/or changed the parameters of operation and the condition of the sensors; some of these stations possess telephonic line and they are interrogated by modem.


The strong motion accelerographs are disseminated to promote research activities on design factors and seismic risk in the Mexico City; through the publication of newsletters, presentations at conferences and seminars, as well as in the group of institutions which contribute to the conservation and upgrading of the Mexican Strong Motion Database, and in the present day it has been edited, with the support of the SMIS (Sociedad Mexicana de Ingeniería Sísmica), the volumes 1 and 2 in CD-ROM format. These disks gather the results of the different Mexican institutions devoted to the register of seismic information and feature a total of 13,545 accelerograms, which have been obtained in the lapse from 1960 to 1999.



Also, CIRES diffuses a newsletter in less than 24 hours to the SOS of the GDF, after have felt an earthquake in the Valley of Mexico. Likewise, a bi-monthly report relating to the activities carried out in the RACM stations is delivered, at the same time it contains information about service, operation and conservation as well as accelerograms that has been gotten in that period of time. It is a main objective of CIRES to have results available for researchers and specialists in seismic engineering from Mexico and abroad.


The continuous service of RACM, until June 2015, has been successful in attracting 5,880 accelerograms measured over the effects of 229 earthquakes. This collection data strong motion meets little more than 252 hours of accelerometric information.


We acknowledge the financial support received from the Mexico City Government Authorities through of the SOS to assure and to carry out the activities of operation and maintenance of the RACM.

Centro de Instrumentación y Registro Sísmico, A.C.
814 Anaxagoras Street, Narvarte. C.P.03020. Mexico, City.
Phone Numbers:(55) 56874542, (55) 56874582
Fax:(55) 56692512
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