Numerical Analysis of Square and Circular Skirted Footings Placed on Sand using PLAXIS ۳D Software

This paper presents the numerical analysis of square and circular skirted footings placed on different sands using the PLAXIS ۳D software. The numerical analysis is done using the Mohr-coulomb (M-C) yield criteria. The size of the footings is considered as ۱۰۰ mm for both the square and circular footings. The three different friction angles (Ø) of sand ۳۶˚, ۴۰˚, and ۴۲˚ are used to study the effect of sand compactness. The depth of the skirt (h) varies from ۰B to ۲B (B is the width of the footing). The surface roughness between skirt-sand and footing-sand is considered partially rough and completely rough. The interface friction factor (δ) for a partially rough and fully rough interface is taken as ۲/۳Ø and Ø. All the tests are conducted by applying a prescribed displacement (s/B) of ۲۰% of the footing size. The results obtained from the present work reveal that the inclusion of structural skirts with the footings appreciably increases the bearing capacity and reduces the settlement of the footing by increasing the skirt depth. The results obtained show that the skirted footing is found to be more effective in loose sand compared to dense sand in increasing the bearing capacity. The numerical analysis results are also verified with the experimental results available in the literature and multiple regression model. This work shows that the prediction of the accuracy of the results is quite good with the experimental results and the generated regression model.

کلیدواژه ها:

Numerical Analysis ، PLAXIS ، skirted footing ، Mohr-coulomb ، bearing capacity