In this paper, the membrane effect of geogrid reinforcement was investigated based on numerical simulation to understand the serviceability and deformation of highway piled embankments under moving vehicle loads. The membrane effect of geogrid reinforcement in low embankments (i.e., the ratio of embankment height to pile spacing is less than 1.5) was clearly emphasized. It has been found that the maximum settlement of geogrid occurs in the central area between the piles, and the maximum tension was concentrated at the corner of the pile cap. Due to the attenuation of the soil arching effect under moving dynamic loads and the punching mechanism, the settlement and tension of the geogrid increased considerably by approximately 35% and 23% compared to those under static loads. A parametric study was also achieved, and the results presented that the geogrid reinforcement tension increased by increasing the pile spacing, embankment height and geogrid stiffness, vehicle wheel load and vehicle velocity. It was also found that the reinforcement tension was most sensitive to the pile spacing among all the parameters considered in this paper, whose magnitude increased by approximately 104% as the pile spacing increased from 2.0 m to 2.5 m under dynamic loads.

Subsoil support is generally ignored in the design of reinforced piled embankments, resulting in a very conservative design for settlement control. This design philosophy may lead to an unnecessary increase in construction costs, especially for embankments constructed over subsoil of medium and high compressibility (i.e., compression index of subsoil larger than 0.2). This paper presents the ground reaction of lightly overconsolidated subsoil in a reinforced piled embankment subjected to cyclic loads for the purpose of investigating the general behavior of lightly overconsolidated subsoil, and it promotes the sustainable development of piled embankment technology. The ground reaction of subsoil under both static and cyclic loads was comprehensively analyzed in terms of settlement and incremental vertical stress, which exhibited approximately the same profile. However, the settlement of lightly overconsolidated subsoil under a cyclic load was 23% larger than that under a static load. A parametric study was then performed under cyclic loads, and the results showed that the vertical stress carried by the subsoil was the most sensitive to the pile spacing amongst all the parameters considered in this paper. The analysis demonstrated an approximately 88% increase in stress when spacing was enlarged from 2.0 to 3.0 m. Finally, a modified analytical method for the ground reaction of lightly overconsolidated subsoil under cyclic loads was presented, and it showed reasonable agreement with the numerical simulation, particularly for relatively low geogrid stiffnesses, low embankment height (<6.5 m), and small pile spacing (e.g., 2–3 m center to center).