Bearing Characteristics and Influence Parameters of Rigid Pile-semi-rigid Pile-geogrid Reinforced Subgrade
Rigid pile-semi-rigid pile-geogrid is an effective method of reinforcing subgrade engineering.The pile-soil interaction of this method is more complicated than that of the traditional pile network structure subgrade,To analyze the bearing characteristics-especially the rigid pile length,pile diameter,pile spacing and geotechnical reinforcement materials and their influence on the settlement of the subgrade and pile-soil stress ratio-the optimization of the design of the composite subgrade reinforcement scheme was investigated under static loading.The results showed that the bearing capacity of both rigid and rigid and semi-rigid piles was mainly shared by the lateral resistance;however,there was some difference in the degree of lateral resistance.The load on the upper part of the embankment was transferred from the center pile to the edge pile in the rigid pile-semi-rigid pile-geogrid reinforced subgrade,and spread along the embankment toward the embankment cross-section.The soil settlement at the top plane of the pile shows a"W"distribution on the cross section,and the rigid pile significantly reduced the soil settlement at the top of the pile.Within a certain range,increasing the pile length,increasing the pile diameter and reducing the pile spacing of rigid piles can reduce the soil deformation of the subgrade and the total settlement of the subgrade by 7.12%-35.96%and improve the bearing capacity of the road embankment to a certain extent.Using geotechnical reinforcing materials in the road embankment,which works together with the gravel bedding,can coordinate the redistribution of the load in the subgrade,making the distribution of internal stress more balanced compared to using geogrids in the subgrade.Compared with geogrids,geocells have three-dimensional structures,which have better effect on reducing soil settlement and regulating load transfer in subgrade.The length of pile body and pile diameter and spacing should be designed reasonably,and suitable transverse reinforcement should be selected according to the upper load and geological conditions.
subgrade engineeringpile top settlementmodel testgeocellfinite element analysisinfluencing parameter