Model Test Studies And Numerical Analyses Of The Vertical Bearing Behavior Of Bored Piles And Pile Groups With Breakage Defects

Broken pile is a kind of common defect in pile foundation. Few researches havebeen conducted on its vertical bearing mechanism. In this paper, three meansincluding model test, field test and numerical simulation were conducted to study forthe vertical bearing capacity of the broken single piles of and group piles in silty soils.A set of simulation methods of the model test of piles indoor was summarized,and a complete and easy-to-control making process of normal piles and broken pileswas proposed in this paper. A series load-settlement curves of normal piles andbroken piles were obtained through a series of tests, respectively. By comparing theanalysis, comes with the preliminary conclusions. Compared with the normal piles,the bearing capacities of the broken piles were greatly reduced. And the reduction isclosely related to the location of the defects. The closer the defect location to theground surface, the smaller the ultimate bearing capacity of broken piles. But for thecase of pile group which contains one broken pile, the impact on the bearing capacityis not as big as like a single pile.On the basis of the indoor model test, a kind of basic approach of the small sizeof bored piles in field tests was conducted, and the whole section broken pile defectssimulation method was put forward. This method can provide reference for the furtherstudy on bored piles. The preliminary results of the indoor test and the field test wasbasically the same.Also by the numerical simulation via PLAXIS2D a series of load settlementcurves of normal piles and broken pile was made, revealing that the results ofnumerical analysis and tests were basically consistent.