Structural behavior of non-uniform mat foundation on weak sandy soil

Rapid urban growth due to increase in population and economic prosperity has witnessed large number of high-rise residential and commercial structures in cities like Abu Dhabi. The weak salty sand that covers many of cities in Middle East requires construction of costly deep foundation. As a solution to the requirement of large numbers of parking spaces for high-rise structures, especially in city areas, require basement-parking provision. To accommodate the high number of parking spaces needed for the building users, the underground floors on a mat foundation are considered as a solution for vertical expansion in a safe and an economic way. The mat foundations are often designed based on simplified design methods. Generally, large number of piles, along with an over-designed uniform thickness mat foundation, can significantly increase the total cost of the foundation for a high-rise building. Although, the application of non-uniform mat foundation can contribute to saving, the structural behavior of these non-uniform mat foundations on soil types similar to the soil of many parts of Middle East is not well studied. To address this gap in knowledge on the behavior of both uniform and non-uniform mat foundations, a parametric study was conducted to explore the structural responses of different schemes of mat foundation on typical soil conditions using finite element analysis. Results from this study provide a better understanding of the behavior of typical uniform and non-uniform mat foundation on a weak sandy soil. The findings of this study suggest some savings in material percentage by changing the mat scheme from uniform to non-uniform thickness subjected to weak sandy soil conditions.