The significance of critical height in the design of piled embankments

The design of piled embankments is extremely complex. Several methods exist for estimating the magnitude of arching occurring in the embankment fill. However these methods involve detailed and often complex calculations, which are considered tedious for preliminary design. Experimental and numerical analysis of piled embankments have demonstrated the existence of a plane of equal settlement, at the critical height, in the arched embankment fill. A new method, based on the critical height of the embankment, is proposed for calculating the magnitude of arching. The critical height is calculated assuming a log spiral shaped shear plane in the embankment fill, above the pile caps. For the case histories examined, the new method compared favorably with existing more complex methods for calculating the magnitude of arching in piled embankments. Copyright ASCE 2007.