Numerical Study of Installation Effect and Inclination Angle on the Pullout Capacity of Helical Multiple Anchors on Excavation Support

Document Type : Original Article

Authors

1 M.Sc. Grad, Department of Civil Engineering, Yazd University, Yazd, Iran.

2 Associate Professor, Department of Civil Engineering, Yazd University, Yazd, Iran.

3 Assistant Professor‌, Department of Civil Engineering, Yazd University, Yazd, Iran.

Abstract

In today’s world, roads are considered the main arteries of the global community. One of the most typical methods to build these routes is stabilizing the excavations on two sides of the roads. Using multiple helical anchors in excavation stabilization is one of the means recently used by many road and geotechnical engineers. The increasing use of multiple helical anchors has led to several laboratories, numerical, and field studies. Therefore, this study employed the FLAC 3D software also a three-dimensional numerical investigation of bearing capacity under different inclination angles in sandy soil. In the present study, the effect of soil installation, which is caused by installing helical anchors in the soil, has been studied on the load-bearing capacity of these helical anchors. For this purpose, first, a verification test is done to validate the modeling approach. Then, by performing a parametric analysis, the effect of different inclination angles, as well as the installation effect on the bearing capacity of the multiple helical anchors, are studied. The present study results show that the maximum bearing capacity of the helical anchors is achieved by the angle of 5 and 10 degrees. In addition, by investigating the installation effect, the bearing capacity of the helical anchors has been significantly reduced with respect to the number of helical plates and the density of soil.

Keywords


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