GEOTECHNICAL BEHAVIOR OF THE CATHEDRAL AFTER 10 YEARS OF THE INTERVENTION OF SUBSOIL

In the year 1989 is advised damage in the vaults of the Cathedral of Mexico city, this alerted on the structural risk having the monument by the large differential settlements accusing; in that year the geotechnical exploration of subsoil began to understand differences in the compressibility of soft clay and establish the unusual geotechnical model of its subsoil allowing to predict the magnitude of future deformations. In addition were carried out topographic and structural measurements, allowing to know the dimensions and inclinations of the structural elements. Based on the results of the Geotechnical study and analyze the evolution of the interstitial water measured groundwater changes, the inclinations of columns and walls was deducted in next 50 years period would increases. This information persuaded the authorities to intervene the subsurface through two actions: a) a corrective that consisted the underexcavation of Cathedral’s and El Sagrario foundations, and b) other preventive to generate selective tightening of the subsoil, which was achieved with the establishment of rigid inclusions and injection of mortar by hydraulic fracturing. Underexcavation works began in August 1993 and concluded in June 1998; Hardening subsoil began in 1998 and concluded in 2001. From 2001 to date both temples have continued observing it instrumentally in this article are presented and discussed the most significant results of these topographic measurements taken between 2001 and 2012, which confirm the beneficial effects both the under-cutting and hardening of the subsoil, which constitutes an important example that is being applied to other monuments of the architectural heritage of Mexico city. Victor Hernandez, Enrique Santoyo and Julio Hernandez