A new detection device was designed by integrating fiber Bragg grating (FBG) and polyvinyl chloride (PVC) tube in order to monitor the slip surface of a landslide. Using this new FBG-based device, a corresponding slope model with a pre-set slip surface was designed, and seven tests with different soil properties were carried out in laboratory conditions. The FBG sensing fibers were fixed on the PVC tube to measure strain distributions of PVC tube at different elevation. Test results indicated that the PVC tube could keep deformation compatible with soil mass. The new device was able to monitor slip surface location before sliding occurrence, and the location of monitored slip surface was about 1–2 cm above the pre-set slip surface, which basically agreed with presupposition results. The monitoring results are expected to be used to pre-estimate landslide volume and provide a beneficial option for evaluating the potential impact of landslides on shipping safety in the Three Gorges area.

Summary For the precast structure with postcast connections, the location of the connection is usually the midspan of the beam, joint core, and beam end. However, the postcast connections located at the midspan of the beam or the joint core would increase the difficulty of construction because of the large dimension of the precast components or reinforcement congestion at joint core, respectively. A connection located at the beam end could decrease the seismic performance the energy dissipation mechanism being disturbed. To balance the requirements on the transportation, construction, and seismic performance, the connection is proposed to be located at one plastic hinge length from the beam end. A quasi‐static test was conducted on three 6 m × 3 m beam‐column joints, including two precast joints and a monolithic joint. The results show that the joint with connections located outside the plastic hinge zone had good seismic performance. When the connection located at the beam end, the ductility, strength, and energy dissipation reduced 8%, 10%, and 30%, respectively. To optimize the postcast location, finite element analysis was conducted and 2h was suggested for the postcast location according to the analysis results.

To focus on the key scientific problem of process control of dynamic catastrophe of high dams, presented for the first time are the modelling theory of liquid-gas-solid tri-phase coupling of the air-cushion isolation control of high dams and its numerical simulation method, and theoretical description of the complicated dynamics problem of the tri-phase coupling-thermodynamics state-material-contact bi-nonlinearity, as well as the simulation analysis of the key effects of dynamic catastrophe of the air-cushion isolated high dam engineering. The analytic solution of plane-wave with rigid-dam body was created. The simulation comparison of dynamic catastrophe processes of 305 m Jinping arch dam with and without seismic control was carried out, and the results were basically in agreement with that obtained from the large shaking table tests, and verify each other. The entire air-chamber and optimized air-cushion with varying thickness were presented to develop a optimization method. The large shaking table tests of the isolated dam model, which is satisfied with the basic dynamic similarity relations, were performed for the first time. The test data seemed to be convincing and were in agreement with the dynamic simulation results of the tested model, thereby providing an experimental verification to the simulation theory and method. The combination experiments of theoretical model and physical model demonstrated that the hydrodynamic pressure of high arch dams can be reduced by more than 70% as well as the first and third principle stresses of the dam body reduced by more than 20%-30%, thereby the global anti-seismic capacity of the high dam being improved significantly. The results have shown that the air-cushion isolation is the prior developing direction of structural control technology of high concrete dams.air-cushion isolation of high concrete dam, liquid-gas-solid multi-field coupling, material-geometry bi-nonlinearity, large shaking table test, hydrodynamic pressure Citation:Liu H W, Zhang S J, Chen J, et al. Simulation analysis theory and experimental verification of air-cushion isolation control of high concrete dams.

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Composite steel plate shear wall (CSPSW), as a new lateral force resisting structure composed of steel plate and concrete slab, is introduced. CSPSWs can fully display the superiority of the steel plate and concrete. Ductility and energy dissipation capacity of the walls are increased and seismic behavior is improved. Recent seismic research around the word of two kinds of CSPSWs, namely, CSPSW with signal steel plate and CSPSW with double steel plates, is presented and discussed comprehensively. Some existing problems in current research of the walls are also reviewed in this paper.