Comparison of Bearing Capacity of Piled Raft Foundations Consisting of Different Number of Piles under Static and Repetitive Loads

Abstract

In this study, large-scale experiments have been carried out at 5th Regional Research and Development Headquarters Engineering of Highways in order to determine the contribution of the piles in the pile-raft foundation to the bearing capacity. The bearing capacity were determined for only the raft, the raft with single pile and the raft with four pile under static and repetitive loading. In the examinations, sand samples which were taken from a river bed were used. The sand was classified as uniform clean sand (SP) according to standarts. As a result of study following results were obtained. Only raft has reached lowest bearing capacity at different alternatives under static loading. When used single pile and four piles at piled raft foundation systems, the bearing capacity has increased by 1.130 and 2.52 respectively under static loading. As the number of piles increased, it was observed that the settlements at piled raft foundations under the same repetitive loading decrease. 

Keywords

• Repetitive load,Static load,Sandy soil,Piled raft foundation

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