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Structural seismic stability is an important content of research in the field of structural engineering safety. Current methods of seismic stability assessment of single-layer reticulated dome structures, supporting engineering decisions regarding the strengthening, repair, or demolition of structures, are complex and do not facilitate engineering applications, so the deep learning action recognition networks to analyze the structural deformation are employed and assessment of the seismic stability. In order to tackle the problem of an insufficient receptive field of structural global change during the dynamic response process within networks, a Dual-Branch Attention Module (DBAM) is innovatively proposed, which enables the effective perception of the global deformation of reticulated dome structures. The DBAM consists of the Maxpooling Channel Attentional (MCA) branch and the Large Kernel Pyramid Attentional (LKPA) branch, which can provide the network with multi-scale global perceptual information, thus enhancing the recognition ability of the model. In addition, the ReticDomeSeismic dataset is created by the mapping relations from the displacement intervals to RGB colors proposed, which contains a large amount of video data on the seismic analysis of single-layer reticulated dome structures under different parameters. The dataset was employed to verify the proposed DBAM method, and the experimental results show that the DBAM improves the Mean Accuracy of base action recognition methods by 4.37% on average, the highest Top-1 Accuracy of 93.48%. Therefore, the method proposed for structural deformation recognition can quickly and accurately assess the seismic stability of single-layer reticulated dome structures, and also provides significant insights and guidance for engineering practice.

Parameter uncertainty associated with concrete arch dams always arises from modeling assumptions and the lack of knowledge or information of the engineering geological situations, especially in the seismic stability analysis of arch dams. In this research, a high arch dam is selected as a case study for probabilistic analysis of the seismic stability performance. The arch dam abutment and the dam are coupled as a system. A comprehensive approach considering contraction joints, boundaries of the probable sliding rock mass and the dam-foundation interface is presented. The contact nonlinearity is solved by using the dynamic contact model with Lagrange multiplier method. The main parameters of the probable sliding block are considered as random variables containing the friction coefficients and cohesions. Both the slippage and sliding area ratio are chosen as the engineering demand parameters (EDP). The sensitivity analysis is performed to reveal the relative influence of each parameter separately by the approximate incremental dynamic analysis (IDA) method. The friction coefficients are shown to be more crucial than the cohesions on the dam’s resistance to seismic instability. The sliding area ratio can be better used for unveiling the sliding process of the arch dam of concern, while the slippage is useful for one to judging the stability of the arch dam under seismic hazards. The Latin hypercube sampling (LHS) with approximate moment estimation is used to investigate the parameter uncertainty to the seismic stability performance of the high arch dam. The results provide a useful reference for using the median/mean-parameter model to accurately estimate the median/mean response of the dam.

Undrained seismic stability of dual unsupported circular tunnels was investigated in this work using a self-developed code for adaptive finite element limit analysis. The so-called pseudo-static method was used to simulate the seismic effects during an earthquake. Accurate upper and lower bounds of seismic stability factor $N_s$ were obtained by using an adaptive remeshing technique incorporated in the code. Comprehensive parametric studies of the problem variables, including the horizontal seismic coefficient $k_h$, the relative spacing ratio $S$/$D$, the relative depth ratio $H$/$D$ and the strength ratio $\gamma D$/$c_u$ were performed to provide dimensionless design tables for practical uses. In addition, visualized results from AFELA were summarized to reveal how the failure mechanism of dual tunnels would evolve with varying problems variables. Numerical results showed that both the stability and failure mechanism of dual tunnels can be much affected by seismic effects which should be carefully considered for a reasonable design in earthquake zones.

The seismic behavior of rock slopes accompanied with discontinuity is heavily governed by the geometrical distribution and mechanical properties of discontinuity. Especially, high and steep rock slopes, which are dominated by sub-vertical discontinuity, are likely to collapse due to toppling failure and it causes serious damage to structures surrounding the slopes. Ten thousands of landslides, collapses and other geological disasters occurred in the Wenchuan Ms 8.0 great earthquake on May 12, 2008 in Sichuan province of central China. The field survey during the disaster investigations indicated that it shows the tensile failure close to the top of slop and the shear failure below it. However, it is difficult to assess quantitatively toppling failure potential. In order to clarify mechanism of toppling failure in rock slopes and evaluation on seismic stability, 2D joint elements around each rock column is proposed to simulate the discontinuity of rock slope, which is different from Goodman joint and composed with normal spring K_n and shear spring K_s without volume. By a nonlinear numerical FEM analysis, the dynamic response of the rock slopes could demonstrate the landslide mechanism. Coupled with the effect of amplification on the toppling, the seismic horizontal acceleration at the top of slopes is often large, and then coursed inertia force would far exceed the tensile strength of rock mass. Eventually, the opening and sliding of joint elements occurs on the slope are identified based on the nonlinear characteristics of the joint elements. The result shows that a toppling failure could have occurred on the slope and the sliding plane also could be observed, which shows agreement with the existing investigation flexural toppling failure during the Wenchuan great earthquake.