STATISTICAL-NUMERICAL ANALYSIS FOR PULLOUT TESTS OF GROUND ANCHORS

Abstract

The paper presents an application of statistical and numerical methods for the determination of the forcedisplacement curves and that of pullout capacity of prestressed grouted ground anchors installed in Miocene clay. A regression analysis of data from a database of acceptance test records for ground anchors to create has been performed, the force-displacement curve of the tested anchor corresponding to the range of loads applied for acceptance tests has been created. A linear regression model, employing the weighted least squares method and robust standard errors techniques were concluded to serve as a reliable statistical method suitable for achieving this goal. The discovered linear regression dependence then served as a lower control limit for the displacement values calculated at the anchor head applying the numerical model. A finite element model has been created to predict the behaviour of ground anchors being installed in fine-grained soils. The developed numerical model that employs Mohr-Coulomb strength criterion constitutive model evaluates the influence of high-pressure grouting by development additional radial stresses and that of an increment of fixed length diameter.