Study On Estimation Of Geotechnical Parameters

The most important characteristic of geotechnical material is complicated variability and remarkable uncertainties of the parameters. Since the extent of variation and actual distribution is unknown, certain hypotheses are produced in projects. The study on the estimation of geotechnical material is the key to reliability analysis of geotechnical engineering which remains one of the most leading directions. In this dissertation, a systematic study is conducted on the estimation of geotechnical parameters applying the theories of classical statistics and Geostatistics respectively in different situations, which is of great significance to develop the measurement and proper choice of geotechnical parameters.The main work is carried out as follows:1. What causes the uncertainties of geotechnical parameters and some available methods for analysis and evaluation are described.2. Portable penetrometer is applied to quick measurement of dry density of the fill of embankments, linear regression, logarithmic regression and polynomial regression are adopted to study the correlativity of water content, dry density and blow count, a large number of in-site portable penetrometer experiments and office geotechnical experiments are conducted, and the rationality and prospect of this method are evaluated.3. Filter paper method is applied in field measurement of matric suction and water content to study the correlativity of matric suction and water content, and the empirical equation of dry density and suction is derived.4. Systematic description of the regionalized variable theory is presented and the theory is applied to study the variograms model and structural analysis in the light of a practical example.5. The local estimation methods including Ordinary Kriging,co-Kriging and Universal Kriging are introduced followed by calculation in the light of practical examples.6. The theory of Geostatistics is applied to Yuncheng-Sanmenxia Expressway Project resulting in the contour maps of compaction estimator and the acquisition of the information of degree of compaction based on the correlativity of degree of compaction and dry density. The application of the theory of Geostatistics is significant to the spatial optimum estimation of geotechnical parameters.