Basal Stability Analysis of Braced Cuts in Clay

The evaluation of basal stability is important in the design of braced excavations in clay. Limitations exist in two common methods of analysis—Terzaghi's method and Bjerrum and Eide's—and their results vary. Two improved methods of analysis, one a direct modification of Terzaghi's and the other based on limit analysis, have been proposed. The modified Terzaghi method provides factors of safety that are close to Bejerrum and Eide's solutions. The factors of safety as obtained from limit analysis are the lowest and are consistent with field observations of classical braced cuts in clay.