Non-linear finite element analysis on single-headed anchor under shear loading in concrete compared to predictive design models.

Abstract

In recent years, advances in technology-aided design tools have made the construction of complex structures increasingly easier. Consequently, there is growing research interest in using different fastening techniques to understand how components of an engineering structure connect to ensure resilient designs. For instance, depending on the installation methods, the construction industry uses a variety of anchorage systems, such as cast-in-place anchors and post-in-place anchors. Previous studies have predominantly focused on understating the behavior of concrete anchors subjected to shear loading utilizing Finite Element Analysis (FEA) explicit dynamic solver. However, there is scanty evidence of work that analyzed the concrete behavior of a single cast-in-place headed anchor subjected to shear loading using an FEA static solver. Understanding the nonlinear behavior of a single concrete-headed anchor under loading and the consequent failure loads associated with concrete edge breakout depends heavily on the type of analysis. This dissertation examines the nonlinear behavior of a single concrete-headed anchor using a concrete model that was created using solid 65 element in Ansys static structural. The proposed model accuracy is validated by comparing numerical study results to experimental test results. However, the impact of the anchors in-group is not taken into account in this study because it solely addresses single-headed anchors loaded in shear. In addition, this study evaluated uncertainties and bias based on i) the Concrete Capacity Design (CCD) model, ii) the European standard (EN1994-2:2009), iii) the analytical predictive models from Anderson and Meinheit (2006), and iv) the Grosser model (2006). While the first two are drawn from the codes, the second two are derived from literature on anchorage with concrete edge breakout failure. The study employed statistical analysis and linear correlation to examine the uncertainties and biases of each predictive model. Overall, the failure loads derived from the numerical study were higher than the loads obtained from the findings of experimental test results. Nevertheless, in some instances, results obtained from numerical analysis were much lower than the experimental test results. This exception points to several assumptions made regarding the constitutive materials law of concrete and steel anchors. The statistical analysis and model uncertainties quantification of each predictive model indicates that the Grosser model is the most excellent predictor of concrete breakout capacity of single-headed anchor subject to shear loading, followed by Anderson and Meinheit (2006), EN2, and CCD.