In this thesis, geosynthetic reinforced pile supported embankments and their available research studies have been presented simultaneously to achieve a better perception about the mechanism of arching in such embankments. Laboratory scale tests were then arranged to investigate the effects of piles cap geometry and geosynthetic properties on the performance of agranular embankment models. Around twenty primary tests were first carried out to determine the testing materials characteristics. The effects of surcharge, tensile strength of reinforcements, distance of piles, and the shape of pile caps on the performance of such embankments were then considered by conducting about seventy tests. In each test, surface settlements at both the centre and abutment of embankment model were measured with precision of 0.01mm. The piles loads were also recorded using load cells of 5gr precision. The embankment behaviour was then evaluated using appropriate performance concepts such efficiency and differential settlements. Altogether, three alternatives were considered for each variable of surcharge, reinforcement type, and shape of caps. Further, tow cases of piles distance were also considered in the experimental tests. Using Design-Expert software, combinatorial effects on of these factors the embankment models were visualized. Totally, it could be concluded from the experimental tests that flat caps have better performance in comparison to other cap shapes. Finally, a full scale geosynthetic reinforced pile supported embankment was also modelled in ABAQUS finite element software to consider the effect of pile and cap on the operation of such a system. Results of numerical modelling had shown that the use of pile and pile cap could significantly enhance the system performance. Key Words: Geosynthetic, Reinforced Pile Supported Embankment, Arching Effect, Efficiency of System, Differential Settlement.