DAMAGES OF SMALL TO MEDIUM SIZE EARTH DAMS DURING BHUJ EARTHQUAKE OF 26 JANUARY 2001

摘要

The M7.7 2001 Bhuj earthquake caused severe damages to earthen dams and embankments, and geotechnical infrastructure facilities in the Kachchh region. Of the 19 small to medium size dams (10-25m high), 9 were severely damaged. Longitudinal cracks along the dam, deep-seated circular sliding of the slopes, subsidence of the crest, lateral spreading of adjoining ground due to liquefaction resulting in large lateral displacements in the darn body, and damage to the spillway segment, are some of the major observations. Liquefaction appears to be the major cause of these failures. Indian code provisions related to seismic design of geotechnical facilities are very primitive. The performance of the earth dams during this earthquake has necessitated an urgent re-look at these provisions. This paper discusses six of the severely damaged earthen dams and embankments, and analyses the causes.