Analysis of the Effect of Pile Skin Resistance Verses Pile Diameter Based on Experimental Research

Marandi Marandi

doi:10.3844/ajassp.2009.114.123

Abstract

In spite of the many recent advances in pile design and execution methods, the quantitative effects of grouted pile skin resistance and form on subsequent pile behavior remains an area for research. There are many parameters involved in the analysis of the bearing capacity of piles and descriptive method theory of the loading effect for each parameter is very complex. Many of these parameters are interrelated and investigation of the relationships leads to complex equations, which cannot be easily solved. The only reliable solution is to study the influence of each parameter by experimental model tests in equipped laboratories. This research presents the results of static compression tests on two model groups of pipe and grouted pile shafts (35mm, 50mm and 60 mm in diameters and 900 mm in length) installed into beds of Yazd siliceous sand (located in southeast Iran). The findings of the experimental research were to the average ultimate loads at failure for grouted piles were approximately 12% higher than for the pipe piles. The pile skin resistance is an effective factor on pile bearing capacity, the load transfer response appears to be more plastic with increasing pile diameter in siliceous sand and the skin resistance of the pile was not linearly proportional to the pile diameter and varied with increase in pile diameter.

Highlights

There are numerous interrelated parameters that influence the axial behavior of a pile subjected to axial load
In spite numerous experimental investigations and theoretical analysis, new data are believed to provide a better insight into the behavior of grouted piles and pipe piles in siliceous sand which; may be considered in future theoretical analysis
This research concentrates on the strength derived from pile roughness and skin resistance with the surrounding soil, which, are two of the main aspects that influence the behavior of piles and requires further attention

Summary

INTRODUCTION

There are numerous interrelated parameters that influence the axial behavior of a pile subjected to axial load. On extraction after the tests, the grouted pile surface was found to be quite uniform (Fig. 5) and it was reasonable to assume that the grout penetration into the surrounding soil due to the core tube penetration was negligible The proof of this procedure was shown in the resultant pile diameters and the fact that the reservoir discharge did not contain traces of the cement slurry. Much research has been carried out on the extent of the effected zone surrounding a single pile installed in granular soils (Meyerhof[12], Kishida[13] and Robinsky and Morrison[14]) The results of these studies confirmed the generally the accepted trends (Poulos and Davis[15]) as discussed below. To apply the compressive load on the piles; a gear jack with a maximum displacement of 40mm was used

EXPERIMENTAL RESULTS

G P 6 0 A v erag e P P 60 A verage

RESULTS