From the perspective of the idea that under certain condition hypothesis B is approximately equivalent to modified hypothesis A in quasiplastic viscoelastic model, a new simplified formula of void ratio in terms of equivalent time was proposed based on YinGraham’s equivalent time rheological model and using time reduction factor to modify the difference between real time and equivalent time. The formula was valid for any suddenly loading and unloading cases, including loading in normally consolidated soil, loading in overconsolidated soil, unloading and loading after unloading. Two simplified formula of void ratio for the multistage construction were established by the means of total consolidation degree method and grading consolidation degree method, respectively. Through comparing with the exact solution and the measured data on site, results show that the calculation error of postconstruction settlement by the new simplified formula of void ratio is obviously smaller than those by the classical method and the old equivalenttime method in singlestage construction. The theoretical duration of surcharge preloading and postconstruction settlement were analyzed by the total consolidation degree method and the grading consolidation degree method respectively. Both results are approximate to the exact solution. As the total consolidation degree method is much simpler than the grading consolidation degree method, the former is suggested to calculate preloading duration and postconstruction settlement in the preloading method.
HU Ya yuan, YANG Qiu hua. Unified simplified settlement formula based on YinGraham’s rheological model. JOURNAL OF ZHEJIANG UNIVERSITY (ENGINEERING SCIENCE), 2016, 50(6): 1009-1017.
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