Proposal of One Comprehensive Ground Improvement Acceptance Criteria Based on CPT Results

摘要

The cone penetration test (CPT) has been widely used as one of the most popular performance test for ground improvement. Most of the acceptance criteria based on CPT result is only correlated with single factor-relative density. It is rarely common to see the acceptance criteria is built based on multi-factors incorporating relative density, liquefaction susceptibility, bearing capacity, and allowable long-term settlement. Therefore one comprehensive acceptance criteria ground improvement is proposed for Al-Zour LNGI project in Kuwait. In accordance with the analysis, the compaction criteria can be built by applying Baldi method based on the site specified correlation between relative compaction and relative density. While for the liquefaction susceptibility criteria, it can be built by the Youd and Idriss method using soil behavior index Ic based on the reclamation quality controlling class. Moreover, the bearing capacity and allowable long term settlement criteria can be built based on CPT test. In order to verify the comprehensive criteria, one zone load test (ZLT) with four CPTs being performed at four corners was analyzed. Based on the CPT result, the performance result might fail if only considering one compaction criteria, however, the ZLT result shown that the bearing capacity along with the predicted long term settlement can meet the design requirement. Hence, the criteria taking into account the liquefaction susceptibility, bearing capacity, and allowable long-term settlement together with compaction degree seem more reasonable and reliable.