A large number of loess tunnels are being built or have been put into operation due to the vigorous development of highways and railways. Due to the broken, porous and multiphase of loess microstructure, the loess will lose its strength rapidly under the loading conditions of rainfall and dynamic, while the shaking table test can be used to simulate this dynamic process much better. Based on the shaking table model of 1/40 loess tunnel and considering the adverse conditions of El-Centro bidirectional seismic wave and rainfall, the seismic response law of loess tunnel is studied in this paper; the damping effect of the loess tunnel structure is discussed by setting the damping layer. The results show that under the action of rainfall and earthquake, the damage of surrounding rock structure precedes that of lining structure; the acceleration of the lining structure changes little under different rainfall conditions, but the strain tends to increase; under the cumulative effect of ground motion, the failure time of surrounding rock structure appears early in the case of heavy rainfall, and the width and depth of crack finally formed are also larger; the setting of damping layer can obviously reduce the strain under different rainfall.
21 January 2023 in KSCE Journal of Civil Engineering
To study the seismic failure mechanism of Plate-Shell Integrated Concrete Liquid Storage Structure (PSICLSS), the mechanical properties of each component under earthquake are studied. The influences of excitation frequency and amplitude on seismic responses of PSICLSS are analyzed. Based on the alternate load path method, the influences of partial component failure on the seismic responses of PSICLSS are studied, and the effects of free surface and structure size on seismic responses of PSICLSS are studied. Results show that the upper connection beams, upper plate and upper shell are easily tension failure. The effect of external liquid sloshing on the seismic response of the structure is more significant. The upper beams have a more significant influence on the structural seismic response. Considering the liquid free surface will cause structural stress increases. With the increase of the structural size, the structural stress, displacement and hydraulic pressure all increase, but the liquid sloshing height does not increase as the structural size increases.
The classical one-dimensional electroosmotic consolidation theory assumes a linear potential distribution independent of time, thereby neglecting the influence of spatiotemporal evolution of soil electrical properties on the consolidation process. To address this limitation, a one-dimensional electroosmotic model test is conducted in this study, revealing the spatiotemporal evolution characteristics of the electric potential field. The results indicate that changes in electrode-soil interfacial properties and the nonuniform evolution of soil electrical parameters are the primary factors responsible for the redistribution of the potential field. On this basis, the Physics-Informed Neural Networks (PINNs) method is introduced for potential field reconstruction, fully leveraging the combination of physical constraints and data-driven approaches to achieve spatial densification of the potential field under sparse observations. Furthermore, a surrogate model characterizing the spatiotemporal evolution of the potential field is constructed and embedded into the governing equation of electroosmotic consolidation as a nonhomogeneous source term, which is then solved numerically using the finite difference method. The computational results demonstrate that the negative excess pore water pressures obtained by the proposed method exhibit smaller magnitudes than those predicted by the classical theory, with the discrepancies primarily concentrated near the anode, reaching a maximum of approximately 120 kPa. The proposed approach provides a feasible pathway for electroosmotic consolidation analysis that accounts for the spatiotemporal evolution of the electric potential field.