Comparative Analysis Of Exsiting Liquefaction Identification Methods

The key technology of real-time alarm liquefaction is using seismic records to identify liquefied. Currently, the main methods of liquefaction identification based on strong motion records are method of Miyajima, method of Suzuki, method of Kostadinov and Yamazaki(method of KY), method of SR—YXM(method of SY). These four methods have done the self-test of the success rate independently in the past, Test results are good. But the self-test consists of three significant shortcomings, First, they use different samples. Second, there is no category for each test site. Third, all the indicators were not verified respectively. Therefore,it is difficult to evaluate the advantages and disadvantages of each method, and it is difficult to improve them.In this paper, we argue that the most essential requirements for methods of liquefaction identification in practical engineering is that these method should have the ability of distinguishing liquefaction site from non-liquefaction soft site. Therefore,seismic record samples should be classified, and examination of the proposed methods should focus on the feasibility for soft and medium soft soil site. In view of this, the paper applys uniform sample of site classification to the comparison of the reliability of the four existing liquefaction identification methods, and gives evaluation results and recommendations for further improvement.The main works include:1. Seek the most essential requirements for methods of liquefaction identification, and determine the principle of selecting the seismic sample records. Select representative samples from the famous earthquake at home and abroad.2. Replicate the three foreign liquefaction identification methods: method of Miyajima, method of Suzuki, method of KY. Apply the new and unified sample to the test of the four methods. Analyse the identification efficiency of the four methods parameters.3. Test the applicability of the method of Miyajima, the method of Suzuki, the method of KY, method of SY on soft soil sites, and analyze the misjudge reasons of the methods to soft soil sites.4. Compare the performance of the four methods under different sites category. Compare the efficiency of parameters of the four methods. Propose the recommendations for further improve the methods of liquefaction identification.5. For the liquefaction conditions of 27 original earthquakes records which epicentral distance is less than 50km from New Zealand earthquake of 2011, apply the four methods to the blind identification test and analyze the preliminary comparative results.