Title: Evaluation of Deep Foundations beneath Buildings Damaged during the 1994 Northridge Earthquake
Author(s): Allen G. Davis
Publication: Symposium Paper
Appears on pages(s): 319-332
Keywords: apartment buildings; drilling; earthquakes; field tests; nondestructive
tests; reinforced concrete
Two 16-story reinforced concrete apartment blocks founded on drilled shafts (CIP piles) were damaged in the 1994 Northridge earthquake. In order to assess the viability of the buildings for retrofit, it was considered necessary to evaluate the integrity of the existing concrete drilled shaft foundations, which were only partially reinforced. This paper describes the use of various nondestructive testing methods for the foundation evaluation, including ground penetrating radar, parallel seismic and impulse response tests. The selected test methods proved to be successfir!, and provided an economical approach while obtaiuing maximum informatron about the integrity and future performance of the hidden foundation.