Showing 3 results for Pile
M. A. Lotfollahi Yaghin, K. Farzad and M. Naghipour,
Volume 23, Issue 1 (7-2004)
Abstract
Similar to random sea waves, forces on the offshore structures due to waves are random. These forces can be mainly divided into two components, namely, inline forces and transverse or lift forces. The random nature of lift forces is more complicated than that of inline forces and both should be combined for design purposes. In the present paper, two different approaches have been used to determine time series of lift forces. Along these lines, the determination of lift coefficients is discussed which have then been used to obtain transverse forces and compared with experimental data. The experimental data used in this study were collected at Delft Hydraulics Laboratory on a full-scale rough vertical cylinder.
A. Eslami, M. Karimpoor Fard and N. Shariatmadari,
Volume 24, Issue 1 (7-2005)
Abstract
In recent years, determining bearing capacity of piles from in-situ testing data as a complement to static and dynamic analysis has been used by geotechnical engineers. In this paper, different approaches for estimating bearing capacity of piles from SPT data are studied and compared. A new method based on N value from SPT is presented. Data averaging,
failure zone and plunging failure of piles are revisited in the light of this new method. A data bank was compiled including 42 full scale pile load tests in sites where SPT was performed close to pile locations. Comparison of current methods by error investigation with statistical and cumulative probability approaches demonstrates that the new method predicts pile capacity with more accuracy and less scatter than others. Therefore, it can be applied as a suitable solution in geotechnical design.
M. Veis Karami, A. Eslami, M. M. Ranjbar and T. Riyazi,
Volume 26, Issue 1 (7-2007)
Abstract
Application of pile-raft foundations, which are known as “compound foundations”, is a suitable alternative in the case of heavy load structures. The interaction behavior of pile raft foundations makes these systems very complex to analyze. Different methods have been proposed to determine the bearing capacity of piled raft systems and distribution of loads between the components, i.e. pile group and mat. These methods are generally categorized into computer-based and conventional methods. In most of these methods, the bearing capacity of the mat, which is often a great portion of the total capacity, is neglected. Also, some model parameters used in these methods, as well as pile group or raft stiffness, cannot be determined by routine tests or calculations. In this study, a number of recent analytical methods of piled raft system are presented. A new method is then proposed which is based on settlement analysis of piled raft foundation and distribution of load between pile group and mat foundation, which regards the interaction of compound systems as an equivalent block foundation. In this approach, settlement is computed based on the concept of neutral plane according to which relative settlement of soil and pile group become the same. Two practical case studies are implemented for validation of the method. The comparison demonstrates favorable results for the proposed method.
