In recent years the idea of using piled raft foundations to reduce the settlement of the raft instead of group pile is proposed by various researchers through experimental and numerical studies. Because of interaction effects between raft-pile-soil under different loading conditions, understanding the behavior of a piled raft foundation is so complicated. The aim of this research is to investigate the behavior of piled raft foundations and unpiled rafts under vertical and vertical-horizontal loading in small-scale. Besides, present loading systems for imposing vertical, horizontal, and combined have some disadvantages. High price, complicated structure, heavyweight, and risk of dealing with high-pressure oil to maintain the needed force are the most important defects of the mentioned systems. So In the present study, an innovative system to impose vertical and horizontal loading is presented. The density of the soil, length, and the number of piles were changed to conduct 20 tests on the unpiled raft and piled raft foundation. According to the results, increasing the number and length of piles reduce the settlement and increase the bearing capacity of the raft under vertical-horizontal loading.

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