Static and Seismic Assessment of Soil Arching in Piled Embankments

Abstract

AbstractPiled embankments are widely used to improve the weak soil characteristics and elevate the ground level for the construction of transport corridors on the weak soil. These embankments allow fast construction and a significant reduction in differential settlement. In the pile-supported railway embankment, most of the imposed load is transferred to the rigid pile through a shearing stress mechanism named as “soil arching.” Several studies contribute to the assessment of soil arching under static loading. However, studies dealing with the effect of the seismic excitation on soil arching in pile-supported railway embankment are scarce. The present study is focused on addressing the effects of static loading and seismic excitation using finite element analysis (FEA) in two-dimensional (2D) state of stress. The FEA results indicate that piled embankment properties such as friction angle, pile, and embankment fill modulus should be improved for the efficient mobilization of soil arching. The arching zone is influenced by varying the pile spacing. In addition, the available design approach shows a variation with numerical results. The soil arching is poorly developed indicating insufficient mobilization under the seismic excitation. This in turn results in the transfer of higher stresses to soft soil. The present study thus presents the detrimental effects of earthquake on transport infrastructure projects constructed in soft soil regions.KeywordsFinite element analysisPiled embankmentSoil archingEarthquake