Uncertainties in Settlement Prediction: KIA Offshore Airport

摘要

Settlement predictions at KIA have been examined and a probabilistic approach used to predict the most probable range of further settlements. From this investigation the following conclusions may be drawn: 1. The Hyperbolic method may be used to predict further settlements of a clay including secondary compression. 2. By applying the probabilistic approach to the Hyperbolic method of settlement prediction, a total "50 years" settlement of 14.3 ±0.5m is predicted at the KIA site; the prediction has a reliability safety index β of 1.0 (i.e., 16% probability of failure). For a value of β of 2.0 (i.e., 2.3% probability of failure) a predicted settlement of 14.3 ± 1.0m is obtained. 3. The probabilistic approach can also be applied to settlement computations based on the e-log p relationship for a clay. The investigation of layer Ma l2 showed that a single value of β cannot be defined for this stratum as the soil properties vary with depth considerably. For layer Ma 12 at KIA, the chance of the computed settlement being exceeded by ±25% has a reliability safety index of 0.75 to 0.95 (i.e., 23% to 17% probability of failure).