Laboratory and Numerical Study of the Behavior of Skirted Foundation Located on a Buried Pipe under Static Axial Loading

Document Type : Research Article

Authors

1 Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Iran

2 Department of Civil and Environmental Engineering, Ruhr-Universität Bochum, Bochum, Germany

Abstract

The bearing capacity and settlement of shallow foundations located on the pipe are usually not acceptable in sandy soils. Therefore, in order to improve the performance of strip foundations, various methods are proposed, as a cost-effective alternative is to add skirts to the edges of the shallow foundation. the addition of the skirt to the edges of the shallow foundation increases the effective depth of the foundation and soil trapped within the skirts, and loads of the structure are transferred to the bottom depth at the level of the skirt tip. In recent years, performance assessment of skirted foundations has become one of the desired topics for civil engineers. In this article, the effect of the burial depth and horizontal distance from the center of the pipe to a single load have been evaluated using numerical and experimental tests. Therefore, the skirted foundations located on the buried pipe with skirts B and 2B (B is the width of the foundation) have been used. The results of the laboratory tests show that by using the skirted foundation with skirts of 2B, the bearing capacity can be increased by more than 300% compared to the strip foundation. A numerical comparison of the skirted foundation with semi-deep and embedded strip foundation shows that the bearing capacity of the skirted foundation was less than 10% different from the semi-deep foundation. Civil engineers can be led towards more economical and accurate designs by using the skirted foundation.

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