Probabilistic And Statistic Analyses On The Characteristics Of Engineering Indexes Of Silt In Taiyuan

In the analyses on the reliability in geotechnical engineering, the principle problem is to decide the probabilistic characteristics of soil indexes. Based on the engineering geologic investigation reports of 22 buildings and the author's own tests in lab (which includes 18 groups of conventional test and compression test, 8 groups of unconsolidated undrained triaxial test and 8 groups of quick direct shearing test), Taiyuan silt is studied in the paper.Firstly, the variability of silt indexes is analyzed. The analyses results show the change laws on variability, in addition, the average value and variability coefficient ranges of silt indexes are given for reference.Secondly, by characteristic statistic, the probabilistic distribution of silt indexes is roughly learned, then the normal and Beta distribution probabilistic models are fitted for generally symmetric distribution indexes, and the Beta distribution models for all indexes owing to their good adaptability. After tested, the indexes of Cuu and m fitted by the Beta models are very good.Finally, the correlation between partial silt indexes is studied. The correlation analyses between physical indexes can be used to decide whether these indexes can be looked as independent variable at the same time in reliability design, furthermore, the correlation between mechanical and physical are also studied and some empirical equations with practical usage are drawn up.The author expects the work done in the paper can play a positive role in richening district data and researching the reliability in geotechnicalengineering.