Geotechnical Engineering Journal of the SEAGS & AGSSEA ISSN 0046-5828
Vol. 51 No. 4 December 2020
A Numerical Approach to Cyclic Consolidation of Saturated Clays
Shay Haq, Tian Ho Seah, Kuo-Chieh Chao, and Cholachat Rujikiatkamjorn
ABSTRACT: A finite-difference numerical code is written in MATLAB to predict excess pore pressures and settlements under stepped/square wave cyclic loads. The numerical code is developed by approximating the Terzaghi’s 1D consolidation equation under time-dependent loading using the Crank Nicolson scheme. A method of applying the stepped/square wave cyclic loads is proposed. The code considers the nonlinear inelastic stress ~ strain relationship and can be used for both homogeneous and heterogeneous layers. The code is validated by comparing the results with analytical, experimental, and field monitoring data in the literature. A good agreement of the results shows that the code is well developed and can be used in predicting the settlements in practice. The analyses show that the maximum steady-state degree of consolidation calculated based on settlement and the maximum steady-state average degree of consolidation calculated based on dissipation of excess pore pressures decrease as the time period decreases. Below a specific time period, both remain unchanged. For a specific time period, both increase as the percentage of loaded portion in a cycle increases. Besides, the maximum steady-state degree of consolidation based on settlement, for a specific time period, increases with an increase in stress levels, which is due to the nonlinear stress ~ strain behavior.
KEYWORDS: Consolidation, Cyclic loads, Finite difference, Crank Nicolson, Settlements.
