A detection device includes an acquirer that acquires a video of each of a plurality of bearings of a structure including the plurality of bearings, an extractor that extracts a dynamic feature corresponding to a plurality of degrees of freedom of each of the plurality of bearings based on the video, and an identifier that identifies, among the plurality of bearings, a bearing whose dynamic feature fails to match a dynamic feature of one or more other bearings of the plurality of bearings.

The invention discloses an arch foot maintaining device and a maintenance method for achieving multi-degree-of-freedom displacement of an arch foot. The device includes a plurality of supporting structures, and the supporting structure includes a base (1), two base supporting seats (7), a hydraulic jack (2), a roller (3), and a roller supporting seat (4). The base (1) is a cuboid with equal length and width, a through hole running through side surfaces of the base (1) is provided on the base (1). A vertical guide groove is provided on each of the two base supporting seats (7). The roller supporting seat (4) is U-shaped and located between the two base supporting seats (7), and the roller (3) is rotatably supported in the roller supporting seat (4). Two ends of a central axis (14) of the roller (3) are respectively located in the two guide grooves, the hydraulic jack (2) is disposed within the base (1), and a top of the hydraulic jack (2) abuts against a bottom of the roller supporting seat (4). A plurality of supporting structures are freely combined to form an arch foot maintaining device, and an arch foot is sectioned and lifting/lowering of each roller (3) is controlled to achieve translation and rotation of the arch foot. The invention is simple in structure, flexible, convenient in operation, and highly adaptable, and therefore may be widely applied in arch foot maintenance and strengthening.

Disclosed is a self-centering viscous damper with pre-pressed ring springs. The self-centering viscous damper with pre-pressed ring springs comprises a first inner cylinder, a second inner cylinder, a third inner cylinder, an outer cylinder, a first end cover, a second end cover, a piston, a piston rod, a ring spring, a first connector, a second connector, a first linking nut, a second linking nut, a first outer cover, a second outer cover, a first end and a second end. Due to the interaction between the inner and outer cylinders, the ring springs are further pressed whether a damper is tensioned or pressed. The ring springs have been applied with pre-pressure which overcomes a frictional force and a restoring force when the ring springs are in an initial equilibrium position.

A sliding pendulum bearing is used to protect a construction against dynamic stresses from predominantly horizontal earthquake excitation with a first sliding plate, a second sliding plate and a slider movably arranged between both sliding plates, wherein each of the two sliding plates has a curved main sliding surface and the slider is in surface contact with a first main sliding surface of the first sliding plate and with a second main sliding surface of the second sliding plate, wherein the first main sliding surface is designed for a first load case and the second main sliding surface is designed for a second load case which differs from the first load case.

The present invention relates to a multipurpose viscous damper (100), comprising: an outer cylinder (101); a core rod (102) positioned in the outer cylinder (101); a core piston (103) positioned in the middle and surrounded the core rod (102); a plurality of bypass pipes (104) extending along the outer cylinder (101), each bypass pipe (104) being connected to the outer cylinder (101) adjacent to the two ends of the outer cylinder (101); an orifice controller (105) located on the bypass pipes (104) for providing initial adjustable damping during low to moderate vibration; and characterized by a pair of inner cylinders (106) positioned inside the two ends of the core rod (102); an inner piston (107) positioned in each inner cylinder (106); a fixed sealing (108) located at the two end of each of the inner cylinders (106); and an orifice (109) located at the two ends of the inner cylinder (106) for allowing fluid flowing from the inner cylinder (106) to the outer cylinder (101) during movement of inner piston (107).

The present invention discloses a multi-dimensional eddy current tuned mass damper, which belongs to the technical field of structural vibration control. A main body of the multi-dimensional eddy current tuned mass damper is composed of two hollow cylinders, wherein an inner hollow cylinder is located in an outer hollow cylinder, ball grooves are formed in the opposite upper and lower walls of the inner and outer hollow cylinders, rolling balls are installed in the ball grooves, and the inner hollow cylinder is rotated in the outer hollow cylinder through the rolling balls; the inner hollow cylinder is provided with an inner cover plate, and the outer hollow cylinder is provided with an outer cover plate, forming a relatively closed box body structure; an orthogonal bidirectional mass element, a stiffness element and an eddy current damping element are arranged in the inner hollow cylinder, and a torsional stiffness element and an eddy current damping element are arranged between the inner hollow cylinder and the outer hollow cylinder. The multi-dimensional eddy current tuned mass damper of the present invention is not only convenient to adjust in terms of mass, stiffness and damping parameters, but also has regular and beautiful appearance, simple structure, and very simple connection with a main structure.

A method for improving the seismic performance of bridges by utilizing the beam body and an energy dissipation and seismic mitigation bridge bearing, which can effectively eliminate the harmful vibration of the bridge pier in the inherent frequency band, thus reducing the stress of the pier body and improving the seismic performance of the bridge pier without introducing external additional mass and looking for an installation space on the pier. The method includes the following steps: obtain the natural frequency fi, the equivalent modal mass Mi and the modal stiffness Ki of the pier in the longitudinal or transverse direction by numerical modal analysis or experimental modal test; determine the mass mi of the beam body; calculate the connection stiffness ki and the connection damping ci between the beam body and the pier; select the bearing system with above connection stiffness ki and the connection damping ci.

A method for improving the seismic performance of bridges by utilizing the beam body and an energy dissipation and seismic mitigation bridge bearing, which can effectively eliminate the harmful vibration of the bridge pier in the inherent frequency band, thus reducing the stress of the pier body and improving the seismic performance of the bridge pier without introducing external additional mass and looking for an installation space on the pier. The method includes the following steps: obtain the natural frequency fi, the equivalent modal mass Mi and the modal stiffness Ki of the pier in the longitudinal or transverse direction by numerical modal analysis or experimental modal test; determine the mass mi of the beam body; calculate the connection stiffness ki and the connection damping ci between the beam body and the pier; select the bearing system with above connection stiffness ki and the connection damping ci.

Seismic protection materials are derived from assemblages of unit cells, where each of the cells has a core, one or more shells disposed about the core, and rigid plates bounding the shells. The cores limit relative vertical movement between the plates, and the shell(s) limit relative lateral motion between the plates. Uncompressed cores are preferably substantially spherical or cylindrical, and can be solid or hollow. Unit cells can be aligned in same or different directions, both within a given layer of cells, and in different layers of cells. Assemblages can have any suitable overall shape and size, depending upon application, and for example can support objects ranging from table top equipment to large buildings and bridges.

Seismic protection materials are derived from assemblages of unit cells, where each of the cells has a core, one or more shells disposed about the core, and rigid plates bounding the shells. The cores limit relative vertical movement between the plates, and the shell(s) limit relative lateral motion between the plates. Uncompressed cores are preferably substantially spherical or cylindrical, and can be solid or hollow. Unit cells can be aligned in same or different directions, both within a given layer of cells, and in different layers of cells. Assemblages can have any suitable overall shape and size, depending upon application, and for example can support objects ranging from table top equipment to large buildings and bridges.