Field tests and analysis of sheet-pile walls with pre-stressed anchors

Field tests on the sheet-pile walls in a highway were performed and the stress of steel bar,lateral deformation of test piles and pulling force of pre-stressed anchor cables were observed.The process of anchor-stretching were reckoned as two conditions signed as BI,BII,while the process of filling was divided into three conditions signed as AI,AII,AIII.It was shown that: ① At the end of condition AI,the maximum moment appeared and the most part of displacement at the top of the test piles appeared during construction.So the time of transition from the filling to the anchor-stretching had great influence on the inner force of the piles.The most dangerous state maybe appeared under the condition AI.② Under the condition BI,the moment value was reduced slightly and the deformation of the piles was restored partly.After anchored,the reduction of the bending moment and the displacement of the top of the piles were unremarkable,so the cables should be loaded as early as possible to make the inner force of the piles more reasonable.③ The growing rate of the moment in the test piles above the ground descended sharply under the condition AII by contrast with that under the condition AI and the moment of the test piles increased more remarkably near the anchor cables than the moment of other part,furthermore,the most remarkable variation of moment of the piles was found at section of the lower anchor under the condition BII.④ The variation of the moment of the test piles mainly occurred near the upper anchor under the condition AIII.It was indicated that there was a great effect of the construction steps on the inner force and lateral deformation of piles,so the construction conditions should be optimized and the checking calculation should be done when the piles were designed.In order to ensure the safety of the walls during construction,the construction procedure should be clearly regulated.