Study of the Effect of an Inclined Bedrock on the Bearing Capacity of Shallow Foundations
- PDF / 3,149,871 Bytes
- 14 Pages / 595.276 x 790.866 pts Page_size
- 75 Downloads / 221 Views
RESEARCH PAPER
Study of the Effect of an Inclined Bedrock on the Bearing Capacity of Shallow Foundations Sina Fatolahzadeh1 · Rasool Mehdizadeh2 · Bahram Nadi1 Received: 5 March 2018 / Accepted: 5 May 2020 © Shiraz University 2020
Abstract In order to determine the bearing capacity of shallow foundations, most of the analytical methods take the assumption that the soil layers below the foundation are homogenous, horizontal and are extended to a great depth. However, in reality, the geological structure under the foundation is much more complex and far from simplifying taken the hypothesis. This can lead to unrealistic bearing capacity values and cause serious difficulties for the concerned structures. This paper aims to study the effect of various parameters such as soil geotechnical properties and geometrical specifications on the ultimate bearing capacity of a shallow foundation on an inclined bedrock, in order to obtain a new equation for determining the bearing capacity. A series of numerical modeling was performed to study the influence of the effective parameters of geotechnical and geometrical properties for calculation of the ultimate bearing capacity. The obtained results were verified through some laboratory small-scale models, and the failure surfaces of a shallow foundation on an inclined bedrock layer were analyzed. Finally, the verified results of the modeling were then evaluated by genetic algorithm in order to determine the new bearing capacity factors ( 𝜇a , 𝜇b , 𝜇c ) for the presented equation. Keywords Bearing capacity · Shallow foundation · Inclined bedrock · Numerical and experimental modeling · Genetic algorithm List of Symbols c′ Cohesion strength 𝜑′ Soil friction angle 𝜓 Dilatancy angle 𝛾 Unit weight 𝛾d Dry density E Young’s modulus 𝜐 Poisson’s ratio e Void ratio Dr Relative density PI Plastic index
* Sina Fatolahzadeh [email protected] Rasool Mehdizadeh rasool.mehdizadeh@univ‑lorraine.fr Bahram Nadi [email protected] 1
Civil Engineering Department, Islamic Azad University Najaf Abad Branch, Esfahan, Iran
GeoRessources, UMR 7359, Université de Lorraine/CNRS/CREGU, Mines Nancy, France
2
D10 Particle-size diameters corresponding to 10% passing the cumulative particle-size distribution curve B Width of the foundation L Length of the foundation H Vertical distance from center of foundation to the rigid layer Df Depth of the foundation 𝛼 Inclination angle S, 𝜃, 𝜆, 𝜉 Failure zone parameters f Horizontal distance of the edge of the foundation to outside edge of the shear failure on conventional failure surface q Total vertical load qu Ultimate bearing capacity UCS Unconfined compressive strength Nc , Nq , N𝛾 Bearing capacity factors Nc∗ , Nq∗ , N𝛾∗ Modified bearing capacity factors 𝜇a , 𝜇b , 𝜇c New bearing capacity factors N𝛾′ Scaled model bearing capacity factor 𝜆 Scale factor 𝜎ci Unconfined compressive strength of the intact rock
13
Vol.:(0123456789)
Iranian Journal of Science and Technology, Transactions of Civil Engineering
𝜎cm
Data Loading...
