Efficiency of methods for determining pile axial capacity-applied to 70 cases histories in Persian Gulf northern shore

Three common approaches to determine the axial pile capacity based on static analysis and in-situ tests are presented, compared and evaluated. The Unified Pile Design (UPD), American Petroleum Institute (API) and a SPT based methods were chosen to be validated. The API is a common method to estimate the axial bearing capacity of piles in marine environments, where as the others are currently used by geotechnical engineers. Seventy pile load test records performed in the northern bank of Persian Gulf with SPT profile have been compiled for methods evaluation. In all cases, pile capacities were measured using full scale static compression and/or pull out loading tests. As the loading tests in some cases were in the format of proof test without reaching the plunging or ultimate bearing capacity, for interpretation the results, offset limit load criteria was employed. Three statistical and probability based approaches in the form of a systematic ranking, called Rank Index, RI, were utilized to evaluate the performance of predictive methods. Wasted Capacity Index (WCI) concept was also applied to validate the efficiency of current methods. The evaluations revealed that among these three predictive methods, the UPD is more accurate and cost effective than the others.

[1]  Murad Y. Abu-Farsakh,et al.  Assessment of Direct Cone Penetration Test Methods for Predicting the Ultimate Capacity of Friction Driven Piles , 2004 .

[2]  M. Davisson.  High capacity piles , 1972 .

[3]  D. Stephenson,et al.  Criteria for comparison of single event models , 1986 .

[4]  Harry G. Poulos,et al.  Pile foundation analysis and design , 1980 .

[5]  K. Loague,et al.  Statistical and graphical methods for evaluating solute transport models: Overview and application , 1991 .

[6]  James H. Long,et al.  Value of Methods for Predicting Axial Pile Capacity , 1999 .

[7]  村山 朔郎,et al.  International Conference on Soil Mechanics and Foundation Engineering , 1947, Nature.

[8]  Abolfazl Eslami,et al.  Bearing capacity of piles from cone penetration test data. , 1997 .

[9]  M. Homaee,et al.  Modeling Transient Evaporation from Descending Shallow Groundwater Table Based on Brooks–Corey Retention Function , 2009 .

[10]  Jean-Louis Briaud,et al.  MEASURED AND PREDICTED AXIAL RESPONSE OF 98 PILES , 1988 .

[11]  Abolfazl Eslami,et al.  Pile capacity by direct CPT and CPTu methods applied to 102 case histories , 1997 .

[12]  M. Randolph,et al.  Design of driven piles in sand , 1994 .

[13]  Mohammad M. Eslami,et al.  Study on optimized piled-raft foundations (PRF) performance with connected and non-connected piles- three case histories , 2012 .

[14]  Craig Loehle,et al.  A hypothesis testing framework for evaluating ecosystem model performance , 1997 .

[15]  Abolfazl Eslami,et al.  Evaluating CPT and CPTu based pile bearing capacity estimation methods using Urmiyeh Lake Causeway piling records , 2011 .

[16]  A. Eslami,et al.  Characterization of the correlation structure of residual CPT profiles in sand deposits , 2013 .

[17]  B. H. Fellenius,et al.  CRITICAL DEPTH: HOW IT CAME INTO BEING AND WHY IT DOES NOT EXIST , 1995 .