Determination of Hydraulic Conductivity Using a Modified Cylindrical-Half-Spherical Piezocone Model

Abstract

To obtain more accurate values of in situ hydraulic conductivity, the present paper has outlined a new method based on the analysis and comparison of existing methods using piezocone data. Owing to results obtained from many numerical simulations and in situ tests, more substantial assumptions are proposed as being more suitable: (1) the flow surface of pore water is assumed to be cylindrical-half-spherical in shape, and (2) the negative exponential function rules the distribution of excess pore water pressure in the soil around the cone. A comparison is carried out between the proposed approach and existing methods based on the graphical and statistical analysis of test data obtained from Quaternary deposits in the Yangtze Delta region. According to the qualitative graphical analysis, the proposed method can evaluate the hydraulic conductivity of soil more accurately. Five different indices and a new graphical analysis using cumulative frequency can be utilized to assess the similar equations. In addition, the results revealed the accuracy and validity of the proposed method, with these methods. The reasonable assumptions, logical derivation, and mathematical analysis together indicate the academic value and application potential of the proposed method. This model and the graphical analysis using cumulative frequency have important guiding significance for the similar analysis.