Ground Movements Caused by Braced Excavations

The causes and patterns of ground movement associated with braced excavations are examined. Field measurements of displacements for braced cuts in sand and soft to medium clay show a relationship between the deflection of the excavation wall and the ratio of horizontal to vertical movement adjoining the cut. A review of various case histories indicates that soil displacement depends strongly on the construction process. Practices are recommended for promoting a stiff bracing system, excavating beneath the lowest braces, and using berms to restrain ground movement.