A combined preparation method of stratified preloading and centrifuge operation for soft clay foundations
LAN Jingyan1，2，XIAN Ganling1，WANG Yongzhi3，4，WANG Tiqiang3，4，LIU Xiangyu1，REN Hongyi1，TANG Zhaoguang3，4
(1. College of Civil Engineering，Guilin University of Technology，Guilin，Guangxi 541004，China；2. Guangxi Key Laboratory of Geomechanics and Geotechnical Engineering，Guilin University of Technology，Guilin，Guangxi 541004，China；3. Key Laboratory of Earthquake Engineering and Engineering Vibration，Institute of Engineering Mechanics，China Earthquake Administration，Harbin，Heilongjiang 150080，China；4. Key Laboratory of Earthquake Disaster Prevention and Emergency Management Department，Institute of Engineering Mechanics，China Earthquake Administration，
Harbin，Heilongjiang 150080，China)
Abstract：The preparation of centrifugal model of soft clay foundation is both the prerequisite and foundation of the test，and at the same time，it is also a technical difficulty. In this paper，a centrifugal model preparation method for saturated soft clay is proposed based on the combination of layered pre-consolidation and centrifuge consolidation under conventional gravity conditions，the principle and steps of layered consolidation method are elaborated in detail，and the changes of pore pressure and vertical displacement in the process of consolidation are analyzed and compared with the theoretical calculations of compression amount. The results show that： for the layered pre-compression consolidation，the settlement rate of 0.2 mm/h and the dissipation rate of excess pore water pressure of 0.2 kPa/h can be taken as the conditions for the consolidation and stabilization of the soft clay model when applying each level of loading；for the centrifuge consolidation，the model achieves the consolidation and stabilization state when the centrifugal acceleration reaches the target value of 5 hours，and the dissipation of the excess pore water pressure of up to 2 kPa/h and the surface vertical settlement up to 0.15 mm/h can be taken as the stabilization conditions for centrifugal consolidation of soft clay model. The research results and test steps can be used to provide methodological references and technical support for the preparation of soft clay centrifugal shaking table tests in the future，which is of scientific significance for improving the preparation accuracy of soft clay centrifugal models.
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2024, Vol. 43 
