Author : M. Eid, A. Hefny, T. Sorour!, Y. Zaghloul, M. Ezzat

A finite element model is established using MIDAS GTS NX 2018 software, in order to simulate the behavior of an instrumented large diameter bored pile, installed in multi layered soil and tested under three different loading and unloading cycles at Damietta Port Grain Silos project site. Modified Mohr-Coulomb constitutive model has been used to define the drained condition for sandy soil layers and undrained condition for clayey soil layers. Necessary soil parameters were determined from extensive laboratory and in-situ soil tests. Numerical results are compared with field loading test measurements and very good agreement is obtained. The effect of dilatancy angle on pile load transfer mechanism was investigated, and results of the study showed important effect for the dilatancy angle on the pile settlement values and the load distribution along the pile shaft. Results obtained also showed that the plastic zone below the base of the pile at failure extended laterally to about seven times the pile diameter and vertically to about 5 times the pile diameter.

Keywords: Large diameter bored pile, full scale pile load test, settlement, pile load distribution, finite element, Modified Mohr-Coulomb constitutive model, load transfer mechanism, pile failure, dilatancy angle, end bearing influence zone

Article published in International Journal of Current Engineering and Technology, Vol.8, No.2 (March/April 2018)