Soil arching effect in reinforced piled embankment for motor-racing circuit: Field tests and numerical analysis

Abstract

When constructing superstructures on soft soils, severe issues including excessive settlements, bearing failures, and large lateral displacements arise and cause challenges for geotechnical engineers. Reinforced piled embankments are being used increasingly for various types of engineering construction such as highway widening and roadway construction, thereby making it crucial to comprehend and evaluate systematically the effect of soil arching, which has a significant influence on the performance of such embankments. This study focuses on two large-scale field tests of the piled embankments for an international motor-racing circuit in China, and the effect of the load transfer platform formed by geosynthetic reinforcement and gravel layer is investigated. Field monitoring data of soil pressures and settlements of pile caps and soils are reported and analyzed, and the test results show that soil arching acts significantly to transfer the load to the pile caps with an increase in loading from the embankment. Geogrids within the gravel layer can not only improve soil arching (reflected by higher stress concentration ratio) but also diminish differential settlements between pile caps and the ground surface. A numerical test considering different influencing factors is also conducted, thereby enabling both studying the effects of varying the field parameters and comparing with the insitu measurements. A proposed numerical model of the reinforced piled embankment is also shown to work well when compared with the results of the field tests. This study enhances the comprehension of soil–pile–geogrid interactions and guides similar projects in the future.