STATISTICAL ANALYSES OF CORRELATION DISTANCES OF LACUSTRINE SEDIMENTARY SOILS IN CENTRAL REGION OF JIANGSU PROVINCE

Correlation distance is a very important parameter for random field theory in modelling soil profiles, and also a key point for the application of random field theory to reliability analysis in geotechnical engineering. Based on the collections of tip resistance indexes from field Cone Penetration Tests(CPT) of a project located in the centre of Jiangsu province, correlation distances of silty clays are statistically calculated by adopting different sample intervals. The influence of sample intervals on the results is also analysed. Hence, a procedure for selecting sample interval is recommended based on scale-matching principle in actual practice. In addition, many in-situ CPT data are obtained from the geotechnical investigation of an expressway in the centre of Jiangsu province. The vertical and horizontal correlation distances of lacustrine sedimentary soils are statistically analyzed by means of mean-crossings, moving average and correlation function. The conclusions of this paper provide not only a new prescription for determining sample interval in statistically estimating correlation distance, but also the characteristic values of correlation distances of regional soils in central Jiangsu. What is more, it can be very helpful to lay a solid foundation for establishing the random field model of regional soil properties and provide essential reference for reliability and statistics in geotechnical engineering in the central region of Jiangsu province.