Time-dependent load transfer behavior of grouted anchors in laterite

Abstract

The load transfer behavior of grouted anchors is time-dependent under long-term (creep) load. This study aims at investigating the time-dependent behavior of grouted anchors in laterite by both physical model test and theoretical simulation. A laboratory creep pullout model test of full-length-bond grouted anchor in laterite was carried out using a special developed apparatus. The creep pullout load–displacement response at anchor head and time history curves of axial strain were tested and presented. The creep behavior on the grout - soil interface was simulated using Merchant rheological model in theoretical simulation. By comparing the experimental data with predictions, the applicability of the proposed theoretical method was validated, and the time-dependent load transfer behavior of grouted anchors was discussed. The impacts of five model parameters on the time-dependent pullout response were further analyzed by parametric studies. It revealed that the tensile force distribution tends to be linear, and the shear stress distribution towards uniformity as time elapsed. Additionally, the time-dependent load transfer behavior for grouted anchors is influenced by the above parameters in various levels. This work provides insights into understandings of time-dependent behavior, and facilitates the service life design practice for grouted anchors embedded in laterite.