Prediction of Ground Settlements Due to Deep Excavations

ABSTRACTS: Effects of ground settlements on adjacent structures have been a critical issue in deep excavations in urban areas. Empirical methods commonly adopted in the past cannot always give reasonable predictions on maximum settlements or settlement troughs. As computers and computer software become more and more popular, engineers nowadays tend to rely more and more on advanced numerical analyses together with comprehensive soil models for predicting the performance of deep excavations. This study uses a simplified method developed by Jen(1998) for predicting ground settlements due to deep excavations in Taipei. The method is founded on a sound analytical framework and has been validated by many projects in Boston area. Since cohesive deposits in Taipei are lean sensitive clay with properties similar to those of the Boston Blue Clay, the method has been used in two excavations in Taipei to see whether it is equally applicable to the Taipei deposits. Reasonable results were obtained leading to the conclusion that the method is not only good for the Boston area but may also be suitable for other areas. However, it is noted that certain parameters used have to be adjusted to suit local ground conditions