Improving Tilted Foundations Over Soft Clay Using Micropiles: Numerical Analysis

Micropiles can be a suitable option for tilted foundations of inclined buildings standing on soft clay, where other options, such as soil injection, are either unavailable or considered to be inappropriate. In the past, the design parameters of the micropiles required to improve the tilted base, such as both the length and the configuration of the micropiles, have not attracted the attention of many researchers. In order to refine their lengths and configurations, this numerical study modeled the tilted foundations underpinned by micropiles. Accordingly, this paper studies the load transfer mechanism of micropiles by analyzing 16 hypothetical cases of renovation of tilted foundations using micropiles. This study was expanded to include two main reasons for differential settlement: various soil thicknesses and different soil properties. The purpose of this paper is to obtain optimized micropiles that may stop inclined foundations from tilting after installation. The numerical model results are calibrated using the available case study data for the rehabilitation of a tilted base over soft clay using micropiles. The results show that the most important factor for controlling tilted foundation settlement is only the micropiles which are on the tilting side, while very long micropiles are not significantly required because the only top length of 50 times the diameter of the micropiles transfers the highest percentage of skin friction from the micropiles to the soil medium.