Journal of Structural and Construction Engineering

Journal of Structural and Construction Engineering

Investigating The Effect of Slope on the Coefficient of Undrained Bearing Capacity (Ncʹ) of Ring and Circular Foundations

Document Type : Original Article

Authors
1 Assistant Professor, Departemnt of Engineering, Islamic Azad University, Ahvaz, Iran
2 Associate Professor, Department of Civil Engineering,. Islamic Azad University, Najafabad, iran
Abstract
Ring foundation is used for foundations of structures such as silos, water tanks and transmission towers. Sometimes these structures are placed in the near or on the slope. Considering that no research has been done on the effect of slope on the undrained bearing capacity of circular and ring foundations.Therefore, investigating the effect of slope on the behavior of ring foundation is very important. In this research, with the help of finite element method and using PLAXIS3D software, the effect of slope on undrained bearing capacity factor (Ncʹ) of ring and circular foundation is investigated. In this research, a ring foundation with a diameter of 2.5 meters and a ratio of inner diameter to outer diameter of 0.2, 0.4, 0.6 and 0.8 was modeled in three dimensions model and the effect of various factors such as angle of the slope, the dimensionless resistance ratio and the ratio of slope height to foundation diameter on Ncʹ was investigated. The results showed that with the increase of the angle of the slope, the amount of Ncʹ decreases linearly, and also with the increase of the ratio of the inner diameter to the outer diameter of the ring foundation, the effect of the slope on Ncʹ decreases.In the numerical analysis, 3 types of failure were observed, 2 of which were due to the failure caused by the bearing capacity and the third type of failure was due to the general failure of the slope. The results showed that with the increase of the dimensionless resistance ratio from 1 to 5, the value of Ncʹ ' increases, and for higher values of the dimensionless resistance ratio, the value of Ncʹ remains constant.
Keywords

Subjects


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  • Receive Date 29 June 2024
  • Revise Date 11 September 2024
  • Accept Date 26 September 2024