Modifying the capacity of shallow foundations to resist uplift forces using structural skirts as a promising...

Uplift forces are an important parameter that geotechnical engineers are keen to study for their impact on shallow footings to reduce the risks resulting from them by inventing methods and techniques that limit these effects; one of these methods is the use of piles. This research paper examines the behavior of using structural skirts under shallow footing exposed to uplift loading as a promising alternative to using piles foundations.

A data logger connected to the loading system, a square footing model, two groups of skirts (chamfered and straight corners) with different properties (length to width ratio, inclination angle, and wings), and two types of single piles with different embedment ratios were utilized under 0.5 and 2 mm/min displacement rates. The behavior and performance of an unmodified footing model, which was placed on loose sand with a relative density of 30%, were examined and compared to those of skirted footing and piled footing under uplift forces.

The findings indicated that augmenting L/B to 2 (where L is the footing length and B is the footing width), the inclination angle to 45° of the skirt with wings, and 0.5 mm/min displacement rate substantially enhanced uplift resistance by 9 times more than the single pile in comparison to the unmodified footing and 10.25 times for L/B to 2, 45° inclination angle with wings, and 2 mm/min, displacement rate.

A significant increase in the uplift capacity of soil was observed by improving its properties by adding a skirt to the shallow footing and making modifications to it using wings. The use of a skirt achieved higher uplift capacity than that obtained from using a pile. Skirted footing demonstrates better performance than the single pile.