Probabilistic Analysis of Braced Excavation for Box Drain Construction in Cuttack

KUMARI, PRATIMA; Samui, Pijush; Burman, Avijit

doi:10.22059/ceij.2024.371955.2012

Probabilistic Analysis of Braced Excavation for Box Drain Construction in Cuttack

Articles in Press

Authors

¹ National Institute of Technology Patna

² National Institute of Technology Patna Bihar, India

³ National Institute of Technology Patna, Patna

10.22059/ceij.2024.371955.2012

Abstract

This study presents a probabilistic failure analysis of a braced excavation system for a 9.0 m deep box drain in Cuttack, Odisha, using Monte Carlo Simulation (MCS) and Subset Simulation (SS) methods. The drain spans 3.0 km through highly plastic clayey soil with low shear strength, requiring excavation and braced techniques. Geotechnical field exploration suggests that the soil along the 3.0 km long stretch of the proposed box drain site has very wide variation. A probabilistic analysis is conducted to ascertain the risk involved in the designed braced excavation system. In probabilistic analysis of the braced excavation system, cohesion and unit weight of soil are treated as lognormally distributed random variables. Spatially correlated random fields along the depth are generated using Pearson Correlation matrix and Markov Correlation function. MCS with 10000 samples have been run to conduct the probabilistic response of the braced excavation system. The paper also presents the results of SS, an advanced version of MCS, that enables rapid probabilistic analysis. Furthermore, the results obtained using MCS and SS are compared to establish the relative superiority of SS over MCS.

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