Ecuadorian isolation

A new hospital in Ecuador, reconstructed following its destruction during a 2016 earthquake, will be far better able to survive future seismic events thanks to the 156 seismic isolators on which it has been built

The general hospital of the city of Chone in western Ecuador, destroyed during a large earthquake in April 2016, required to be rebuilt with two major priorities: the reconstruction should be as quick as possible to enable it to resume serving the local population, and the new building should be able to withstand any similar seismic events in the future – thereby protecting lives, saving reconstruction costs, and avoiding loss of service when it is needed most.

In order to meet these objectives, it was decided to isolate the building from future violent ground movements by supporting it on isolator bearings. Of the various types of seismic isolators available, which also include LRBs and HDRBs, isolators of the pendulum type were preferred considering the project’s specific needs. 156 pendulum seismic isolators of type RESTON®PENDULUM were selected for use (of the DUPLO variety, with two curved sliding surfaces for translation – one above and one below the central rotation unit). Two further units were fabricated for prototype testing, which was conducted at Sismalab in Italy, to verify seismic performance in advance of use. Following design of the seismic isolators by mageba to meet all requirements, and fabrication in mageba’s Shanghai factory, they were shipped to site in closed containers and installed under mageba supervision – ensuring proper performance of these vital protective devices when the next earthquake strikes the region.

Building owner: Ministry of Public Health
Building designer: Consulsismica Sísmica Ingenieros Consultores Cia. Ltda.
Construction contractor: China CAMC Engineering Co. Ltd.

View of the hospital construction site in Chone, Ecuador

Representation of a RESTON®PENDULUM DUPLO seismic isolator bearing (cross section showing only half of bearing), in which its various spherical sliding surfaces can be seen – two for translation, one for rotation

Cross-section drawing showing how the RESTON®PENDULUM DUPLO seismic isolator bearing allows large horizontal displacements during an earthquake while temporarily raising the structure and dissipating energy through friction, before re-centring the supported building after the event

Two specimens of the bearings, as designed and manufactured for this project, were subjected to prototype laboratory testing at Sismalab, Italy

Unloading on site after transport from Shanghai in closed shipping containers for maximum protection, carefully packed to avoid damage

Lifting of one of the 156 seismic isolator bearings into place on site

Positioning of a seismic isolator on its concrete pedestal

Precise levelling of a seismic bearing using a specially constructed installation frame, before grouting

Checking of installation by mageba’s installation supervision staff