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http://dx.doi.org/10.9720/kseg.2016.4.485

Probabilistic Optimization for Improving Soft Marine Ground using a Low Replacement Ratio  

Han, Sang-Hyun (Department of Civil Engineering, Seoil University)
Kim, Hong-Yeon (Technology Research Division, Sambu Construction Co., Ltd.)
Yea, Geu-Guwen (Technology Research Division, Sambu Construction Co., Ltd.)
Publication Information
The Journal of Engineering Geology / v.26, no.4, 2016 , pp. 485-495 More about this Journal
Abstract
To reinforce and improve the soft ground under a breakwater while using materials efficiently, the replacement ratio and leaving periods of surcharge load are optimized probabilistically. The results of Bayesian updating of the random variables using prior information decrease uncertainty by up to 39.8%, and using prior information with more samples results in a sharp decrease in uncertainty. Replacement ratios of 15%-40% are analyzed using First Order Reliability Method and Monte Carlo simulation to optimize the replacement ratio. The results show that replacement ratios of 20% and 25% are acceptable at the column jet grouting area and the granular compaction pile area, respectively. Life cycle costs are also compared to optimize the replacement ratios within allowable ranges. The results show that a range of 20%-30% is the most economical during the total life cycle. This means that initial construction cost, maintenance cost and failure loss cost are minimized during total life cycle. Probabilistic analysis for leaving periods of shows that three months acceptable. Design optimization with respect to life cycle cost is important to minimize maintenance costs and retain the performance of the structures for the required period. Therefore, more case studies that consider the maintenance costs of soil structures are necessary to establish relevant design codes.
Keywords
Low replacement ratio; Soil improvement; Life cycle cost; Probabilistic analysis; Granular compaction pile;
Citations & Related Records
Times Cited By KSCI : 3  (Citation Analysis)
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