Document Type : Original Article
Authors
1
CIVIL ENGINEERING DEPARTMENT ,Faculty of Engineering Modern University, Cairo, Egypt
2
Civil Development, Faculty of Engineering, Al-Azhar University, Qena City, 01234, Qena, Egypt
3
Civil Development, Faculty of Engineering, Al-Azhar University, Nasr City, 11884, Cairo, Egypt.
Abstract
The study explores the challenges associated with constructing structures over weak soil layers. It presents a novel solution involving the utilization of granular piles made from gravel to enhance soil properties and counteract issues such as excessive settlement and pronounced lateral deformation. The investigation is conducted within the framework of the Jawharat Al-Fustat residential project, a development project comprising 45 residential buildings in the Ain Al-Sira area in Cairo governorate, Egypt. The project site consists of three layers of soil (Historical backfill & silt clay with interlayers of sand). The current study presents the effect of soil properties, granular pile dimensions, spacing between piles, and replacement soil thickness on the behavior of structures and the replacement ratio. Plate load tests were carried out within the natural at the foundation level, and over granular piles after one month of installation. The results refer to the significant improvement in the bearing capacity of soil attributed to the use of granular piles, which leads to increased strength and deformation properties of the weak soil. Field investigations confirm the feasibility of using granular piles incorporating gravel, combined with vibratory compaction and vibration replacement techniques, which effectively enhance the performance of buildings constructed on weak soils. The field measured on-site settlement values were compared with those analytically estimated using Terzaghi’s approach, and the finite element methods (PLAXIS 3D). The results show an increase in the bearing capacity of the improved soil by approximately (95% to 89%) compared to natural soil and a significant decrease in soil settlement when using granular piles compared to natural soil, On the other hand, the settlement measured on site was much lower than estimated. This is due to attention to the quality of implementation work and the short period of monitoring settlement values.
Keywords
Main Subjects
)
View on SCiNiTO