Dear Professors

Concerning our visit, I have a couple of important things to tell you.

The first thing is that I have contacted Los Andes University and The Colombian Association of Seismic Engineering, both groups deeply involved in the activities of evaluation of the earthquake.

In Los Andes University I have contacted the dean of the Engineering department (professor Alberto Sarria) which told me we could arrange I meeting at the University in Bogota city with our team.

I also contacted the president of the Colombian Association of Seismic Engineering (Dr. Omar Dario Cardona) who gave me a summarized report about the present situation of the region, and the activities they have been doing up to know. He also gave me several useful hints that could be helpful for our mission. Following I attach the English translation of the text originally in Spanish.

Nelson E Pulido

Dear Nelson

Thank you for your message. At present INGEOMINAS who has been leading the evaluation visits to the epicentral area did not find any surface break. According to Los Andes University and the OSSO (Western Colombia Seismic Observatory) the earthquake apparently was not produced by a branch of the Romeral Fault as we initially though.

Once again the earthquake showed the necessity to enlarge, support and promote formally the seismic microzonation of Armenia, Pereira and Manizales cities.

At a first glance, a clear lesson from this earthquake is the benefit that comes from the application of the Seismic Resistant code. A preliminary evaluation in Armenia city showed that the buildings that were designed after 1984, year in which the first official Seismic Resistant Code of Colombia was set up, had only minor structural damage. Most of the buildings that collapse were very old, adobe houses, non reinforced masonry houses, all of them constructed before 1984. The peak accelerations at Armenia were 0.12g in rock and 0.6g in soft soil. In Pereira city 50 km north of the epicenter, 0.11g in rock and 0.4g in soft soil were recorded.

Concerning the evaluation of the damaged structures it has been very efficient in Pereira city (less affected than Armenia city). More than 3000 inspections to the structures have been done and 1000 are still to be done. Many groups of engineers from several parts of Colombia have visited the affected zone, but a lot of help is still needed to accomplish this evaluation work.

In Armenia city and neighbor towns (the heavily affected zone) it has been very difficult to organize the evaluation work. The Colombian Association of Seismic Engineering has been supporting the local teams of engineers, but an efficient operation of the work has not been yet established. However the situation is improving right now with the normalization of the flights between Bogota and Armenia and Bogota and Pereira.

If there is some interest of sending a team to the disaster area, my recommendation is that the team should be self-sufficient. They should try to rent some car from Pereira or Manizales. Inside Armenia and the neighbor towns there is no transportation available and there is even restrictions for the circulation.

(In our case we will have access through INGEOMINAS)

Respecting the hotels it is advisable to stay at Pereira since in Armenia there is almost no hotel availability.

In Armenia, teams like the one sent by EERI, has faced several problems with the transportation, which has made difficult the evaluation work of the damaged structures. Once the emergency gets more stable it will be easier to access to the zone.

Omar Dario Cardona

President of the Colombian Association of Seismic Engineering (AIS)