THIRTEENTH RANKINE LECTURE: PREDICTIONS IN SOIL ENGINEERING

THIS LECTURE EMPHASIZES AND ILLUSTRATES THE IMPORTANCE OF PREDICTIONS TO THE PRACTICE OF CIVIL ENGINEERING. PREDICTIONS ARE EXAMINED AND CLASSIFIED, AND COMPARISONS ARE MADE BETWEEN PREDICTED PERFORMANCE AND MEASURED PERFORMANCE FOR EIGHT CONSTRUCTED FACILITIES. ALTHOUGH THERE ARE MANY TECHNIQUES FOR PREDICTING INTERNAL STRESSES, DEFORMATIONS AND STABILITY FOR A GEOTECHNICAL FACILITY, THE APPLICATION OF THESE TECHNIQUES HAS LIMITATIONS. THE MAJOR LIMITATIONS ARE THE DIFFICULTY OF DETERMINING FULLY AND ACCURATELY THE FIELD SITUATION AND THE MECHANISMS WHICH WILL OCCUR, AND THE SELECTION OF SOIL PARAMETERS TO USE WITH PREDICTION METHODS. THE GREATEST NEED APPEARS TO BE FOR DEVICES AND TECHNIQUES TO DETERMINE, IN SITU AND CONTINUOUSLY WITH DEPTH, FUNDAMENTAL SUBSOIL PROPERTIES, SUCH AS STRESS, STRENGTH AND STRESS-STRAIN MODULUS. (A)