A Numerical Analysis Of Soil Arching In Piled Reinforced Embankments

The piled reinforced embankment consisting of embankment fill, geosyntheticreinforcement, pile caps, piles and soft soil. In recent year, it has been widely used athome and aborad, because of its small settlement, high stability and rapid construction.The bearing principle of piled reinforced embankments is complex. This paperestablishes a3D numerical model of piled reinforced embankment by using finitedifference software FLAC3D. The soil arching, the interaction between pile and soil andthe height of the equal settlement plane are analyzed under the pile unembedded in softlayer and embedded in soft layer.Firstly, the article analyzes the influences of the time on the earth pressure of thepile cap, the earth pressure of the pile soil and the pile efficacy. The pile embedded insoft layer or not have no significant impact on pile efficacy. The pile efficacy issignificantly affected by the pile spacing to the cap size ratio, the embankment height tothe pile spacing ratio and the internal friction angle of the embankment fill. Thegeosynthetic reinforcement tensile strength and the cohesion of the fill have little effect.Hewlett&Randolph’s and Chen Yunmin’s methods and measured date are in fairagreement. However, the method in BS8006is great different with measured date.Then, this article analyzes the effect of the interaction between pile and soil withtime, and analyzes the influences of the time on the settlement of the pile and soil, thepile axial force, the pile skin friction and the location of the neutral point. With thechange of the time, the pile axial force, the pile skin friction and the location of theneutral point are changing. The pile embedded in soft layer or not have large influenceson the location of the neutral point. Thirdly, the height of the equal settlement plane is investigated in detail. In the caseof the embankment load, the pile embedded in soft layer or not have no influence on theheight of the equal settlement plane. The height of the equal settlement plane issignificantly affected by the cap clear spacing, the embankment height and the internalfriction angle of the embankment fill. The geosynthetic reinforcement tensile strengthand the cohesion of the fill have little effect.Fourthly, the height of the equal settlement plane is investigated under the trafficload. In the case of the embankment load and the traffic load, the pile embedded in softlayer or not have no influence on the height of the equal settlement plane. The height ofthe equal settlement plane is significantly affected by the traffic single axle axle load,the cap clear spacing, the embankment height and the internal friction angle of theembankment fill. The geosynthetic reinforcement tensile strength and the cohesion ofthe fill have little effect.