Mitigating the uneven settlement of nearby strip footings on loose saturated sand using concrete pedestals: A model test study

Document Type : Article

Authors

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

2 Geotechnical Engineering Research Center, International Institute of Earthquake Engineering and Seismology, Tehran, Iran.

3 Department of Civil Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan, Iran.

Abstract

Abstract: Adjacency and interfering of footings are a matter of importance in geotechnical engineering. The researchers have focused on the adjacency of the footings by several approaches, but the mechanism of nearby footings under unequal and non-simultaneous surcharges have not been explored to date. In this study, two series tests were conducted using small scale 1g models to investigate the behavior of the two adjacent footings under reinforced and unreinforced soil conditions. The footings were installed with different spacing and rested on loose saturate sand. The ultimate bearing capacity, settlement, and tilting of footings were evaluated when the footings are rested on unreinforced sand as well as the sand bed reinforced by concrete pedestals. The results indicate that reinforcing the new footing by three concrete pedestals in the spacing to footing's width ratio (S/B) of 0 (i.e., two coherent footings) results in 67% increase of the bearing capacity of the new footing compared to that of the unreinforced condition. Also, the settlement and tilting of the old footing adjacent to the new footing decrease respectively up to 250% and 600% in comparison to those of the unreinforced condition.

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