(1. Faculty of Engineering，China University of Geosciences，Wuhan，Hubei 430074，China；2. Engineering Research Center of Rock-soil Drilling and Excavation and Protection，Ministry of Education，China University of Geosciences，Wuhan，Hubei 430074，China；3. College of Civil Engineering and Architecture，Guangxi University，Nanning，Guangxi 530004，China；4. Guangxi Key Laboratory of Disaster Prevention and Structural Safety，Guangxi University，Nanning，Guangxi 530004，China)
Abstract：Based on the equivalent assumption of elliptic cylindrical drain and the linear loss law of the vacuum degree in the prefabricated vertical drain(PVD)，a solution for calculating the radial consolidation of PVD combined with vacuum preloading was proposed. The shape effect of PVD was discussed and the influence of relevant parameters on the foundation consolidation was analyzed. Case study was performed to validate the rationality of the present solution by the comparison between the settlement curve calculated by the present solution and the measured settlement curve，and the consolidation behavior is detailed investigated on the basis of the present solutions. The results show that，when considering the shape effect of PVD，the elliptic cylinder equivalent method is the optimum choice and the result calculated by the perimeter equivalent method is closer to that by the elliptic cylinder equivalent method. Increasing the loss coefficient of the vacuum degree or the vacuum pressure on the top of PVD can accelerate the discharge of pore water in the foundations，speed up the descent rate of the water table and lower the final water table. As the parameter κ increases，the consolidation rate of the overall foundation slows down.
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2019, Vol. 38 
