Large-Scale Experiment and Numerical Evaluation of Effective Parameters of Micropile Pullout in Sandy Silty Soils (Case Study: Bandar Abbas City)

Document Type : Original Article

Authors

1 Department of civil engineering, faculty of engineering, University of Hormozgan, Bandarabbas, Iran.

2 M.Sc., Grad., Geotechnical Engineering, University of Hormozgan, Bandarabbas, Iran.

Abstract

In most civil construction projects, if the soil is not adequate, it is necessary to improve and increase soil bearing capacity to carry out the compressive force, weight and earthquake forces. Also, due to the huge uplift force of some structures during an earthquake or wind force, it is essential to control the related forces. Micropile installation is very quick in comparison with other methods due to the feasibility of implementation, the ability to apply in various conditions and the possibility of implementing simultaneously with other construction stages. In this paper, a case study was carried out on the utilizing micropile for improving the sandy silty soil in a project in Bandar Abbas, and also the stages of micropile loading experiments have been described. Afterwards, the details and results of the tension tests on one of the micropiles at the project site were studied. In addition, the effect of parameters such as length, diameter and height of the improved soil layer has been investigated by using the finite element method. The results demonstrated that by increasing the length and diameter of micropile, the amount of settlement decreases significantly and with increasing depth of soil improvement, the amount of micropile settlement decreases.

Keywords


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