Analytical models and solutions for consolidation of composite foundation with multiple types of reinforcements
LU Mengmeng1，2，BAI Yao1，2，LI Hongjun3，LI Dongxu1，2，LI Chuanxun4
(1. State Key Laboratory of Geomechanics and Deep Underground Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221116，China；2. School of Mechanics and Civil Engineering，China University of Mining and Technology，Xuzhou，Jiangsu 221116，China；3. Zhejiang Real Estate Division，Greenland Holding Group，Hangzhou，Zhejiang 310015，China；4. Faculty of Civil Engineering and Mechanics，Jiangsu University，Zhenjiang，Jiangsu 212013，China)
Abstract：In recent years，the technique of composite ground presents a trend from using a single column type to the combined use of multiple types of columns. This paper takes the combined composite ground improved by prefabricated vertical drains(PVDs) in combination with impervious columns as the research object. In view of the different arrangements of piles，different unit selection methods are employed. Accordingly，three analytical models for consolidation of the combined composite ground are proposed，including the outward flow model(Model A)，the inward flow model(Model B) and the outward-inward bidirectional flow model(Model C). Then a unified solution for the three models is derived. Based on this，detailed solutions are further obtained for instantaneous loading，linear loading，multi-staged instantaneous loading and multi-staged linear loading. Finally，the consolidation behavior of the combined composite foundation is analyzed by a series of the parametrical analysis. The results show that the present solutions are able to consider comprehensively the effects of the well resistance and smear effect of the PVDs，as well as disturbance effect of the constructions of the impervious columns，compared to the previous studies. Moreover，the Model C is more universal to cover all the cases of regular layout patterns of the PVDs and the impervious columns. A smaller well resistance of the PVDs，or a denser layout of the PVDs and the impervious columns，or a higher compression modulus of the impervious columns，will lead to a faster consolidation of the combined composite ground.
卢萌盟1，2，白 垚1，2，李红军3，李东旭1，2，李传勋4. 多元组合桩复合地基固结解析模型与解答[J]. 岩石力学与工程学报, 2021, 40(S2): 3301-3312.
LU Mengmeng1，2，BAI Yao1，2，LI Hongjun3，LI Dongxu1，2，LI Chuanxun4. Analytical models and solutions for consolidation of composite foundation with multiple types of reinforcements. , 2021, 40(S2): 3301-3312.
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2021, Vol. 40 
