(1. College of Civil Engineering and Architecture, Henan University of Technology, Zhengzhou, Henan 450001, China; 2. School of Civil Engineering and Architecture, Zhejiang Sci-Tech University, Hangzhou, Zhejiang 310018, China; 3. Institute of Engineering Mechanics, China Earthquake Administration, Harbin, Heilongjiang 150080, China; 4. MOE Key Laboratory of Soft Soils and Geoenvironmental Engineering, Zhejiang University, Hangzhou, Zhejiang 310058, China; 5. School of Water Conservancy and Transportation, Zhengzhou University, Zhengzhou, Henan 450001, China)
Abstract：Addressing the subgrade featuring a high-saturation upper layer and a low-saturation lower layer induced by the pot cover effect, this paper simplifies the covering layer as an impervious boundary and the unsaturated subgrade into a pot cover layer and a non-pot cover layer, thereby establishing a one-dimensional transient response analysis model for a double-layer unsaturated soil column. First, the displacement field is decomposed into its static and dynamic components, and the boundary conditions are rendered homogeneous. The characteristic equation is then solved to obtain the system?s eigenvalues and eigenfunctions. Finally, the method of undetermined coefficients and precise time integration method are used to directly provide a semi-analytical solution to the problem in the time domain, which can effectively avoid the numerical instability issues associated with the Laplace method. The correctness of the model and solution in this paper is verified through degeneration. The results of the example calculations show that the pot cover effect markedly alters the pore water pressure response under dynamic loading. As the water content of the pot cover layer increases, both the excess pore water pressure and the solid displacement increase. When the water content is nearly saturated, the peak values of pore pressure can reach 14.5 times the initial water content, respectively. Therefore, in engineering practice, it is necessary to pay attention to the dynamic disasters caused by the pot cover effect.
引用本文:
赵 云1*，吉姿洁1，陈樟龙2，单振东3，凌道盛4，徐 平5. 锅盖效应下双层非饱和路基瞬态响应半解析研究[J]. 岩石力学与工程学报, 2026, 45(9): 2863-2874.
ZHAO Yun1*, JI Zijie1, CHEN Zhanglong2, SHAN Zhendong3, LING Daosheng4, XU Ping5. A semi-analytical model for transient response of double-layer unsaturated subgrade under pot cover effect. , 2026, 45(9): 2863-2874.
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2026, Vol. 45 
