1907 Static Liquefaction Flow Failure of the North Dike of Wachusett Dam

Abstract

A static liquefaction flow failure occurred in the upstream slope of the North Dike of Wachusett Dam near Clinton, Massachusetts on April 11, 1907 during the first reservoir filling. The fine sands of the upstream dike shell liquefied and flowed approximately 100 m horizontally into the reservoir. This paper presents a description of the construction of the North Dike, failure of the upstream slope, and the results of stability analyses that were conducted to estimate the shear strength mobilized in the liquefied soils during failure. Analyses of the postfailure geometry, the prefailure geometry, and an analysis incorporating the kinetics of failure were conducted. The back-calculated shear strength considering the kinetics of failure is in agreement with other liquefaction flow failure case histories published in the literature. As a result, it is recommended that the kinetics of failure be considered to determine the shear strength mobilized during a liquefaction flow failure.