Based on recent research by Li and Liu in 2011, this paper proposes the application of support vector machine- (SVM-) based semiactive control methodology for seismic protection of structures with magnetorheological (MR) dampers. An important and challenging task of designing the MR dampers is to develop an effective semiactive control strategy that can fully exploit the capabilities of MR dampers. However, amplification of the local acceleration response of structures exists in the widely used semiactive control strategies, namely “Switch” control strategies. Then the SVM-based semiactive control strategy has been employed to design MR dampers. Firstly, the LQR controller for the numerical model of a multistory structure formulated using the dynamic dense method is constructed by using the classic LQR control theory. Secondly, an SVM model which comprises the observers and controllers in the control system is designed and trained to emulate the performance of the LQR controller. Finally, an online autofeedback semiactive control strategy is developed by resorting to SVM and then used for designing MR dampers. Simulation results show that the MR dampers utilizing the SVM-based semiactive control algorithm, which eliminates the local acceleration amplification phenomenon, can remarkably reduce the displacement, velocity, and acceleration responses of the structure.

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Taking the demolition blasting of complex structure of continuous multi-span aqueduct as the research object and combining with the importance analysis of safety factors in safety evaluation, the blasting scheme, reliability of electric blasting network, pretreatment quality, protection of buildings around the blasting area and safety protection are emphatically studied. The numerical model of aqueduct is established by LS-DYNA. Through the simulation analysis of the whole process of aqueduct blasting demolition and collapse, the blasting breakpoint and the design of pretreatment notch are reasonably determined. Carry out the equivalent electric blasting network test and field blasting test to check the reliability of the blasting network and determine the single hole charge. By the analysis and verification of safety parameters such as blasting shock wave, collapse vibration and safety distance, the active protective measures are taken to protect the important structures and public facilities within the blasting area. The blasting effect and monitoring data show that the safety technical measures can effectively control the safety risk of aqueduct blasting demolition.

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Carbon fiber–reinforced polymer (CFRP) sheets have been widely applied in civil engineering, and the bonded materials are important components in the practical strengthening process. Presently, epoxy adhesive is the most widely used cementation material, but the inorganic materials are developing rapidly. This article reviews the taxonomy and origin of cementation material used in civil engineering as structural adhesives to create the bond between CFRP and summarizes the properties of epoxy adhesive, alkali-activated cementing material, magnesium oxychloride cement, and cement-based composite material. The conclusion shows that using an inorganic adhesive as a binder can fix the temperature problems of organic materials and improve the bearing capacity of reinforced concrete structures. At present, the inorganic adhesive also has weaknesses, which indicates the future research directions.