Experimental investigation of circular piled raft foundation under vertical load in cohesionless soil
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Abstract
A shallow foundation on cohesionless soil cannot withstand higher loads; a piled raft foundation is preferred because it combines the bearing capacities of piles and rafts. In this study, a series of experimental tests were conducted for various parameters such as pile length, raft thickness, soil density, and pile arrangement patterns to study the complexities of pile and pile group behavior under vertical loading. Piled and unpiled rafts were tested and compared using circular rafts under various soil conditions. The findings revealed that increases in the pile length, raft thickness, and soil density enhanced the bearing capacity and decreased settlement. A 35% increase in load-bearing capacity was obtained when the compaction level increased from loose to very dense, and a 75% increase in capacity was obtained when comparing the shortest piles to the longest ones. As a result of this model analysis, the pile raft system with an improved pile and raft design was found to be more efficient. Providing an alternative foundation option for large constructions may make this foundation system more affordable.
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