A Reliable Method of Analysis for Geotechnical Data

Geotechnical engineering is the art of making decisions in the presence of uncertainty, where real world problems are treated and this is associated with uncertainties arising from various sources. The sources of uncertainty may be divided into uncertainties of nature and uncertainties of mind. The uncertainties of nature are due to variation of encountered phenomena, e.g., the shear strength in a soil. This is reduced by obtaining more reliable data via the results of tests. The uncertainties of mind are related to the modelling, which may be reduced by change of philosophy. Here, the data is considered as variable instead of random so is reliable. Based on logical reasoning and concise mathematics a reliable formulation, i.e., the change of state philosophy which is digested in the Persian curve is proposed. The Persian curve method is free of uncertainties of mind. In the presented paper the Persian curve method is used to manage the variable geotechnical data in a form that can easily be used in practical geotechnical work for decision making and design.