A C-shaped steel-friction damper combined energy dissipation structure and method

Abstract

The present invention is a C-shaped steel-friction damper combined energy dissipation structure, which includes a connecting base, a large C-shaped steel energy dissipation device and a friction device; the connecting base includes a symmetrically arranged left connecting base and a right connecting base, and the large C-shaped steel energy dissipation device and the friction device are installed between the left connecting base and the right connecting base; the C-shaped steel-friction damper combined energy dissipation structure is arranged at the connection position of the pier column and the tie beam, and when subjected to earthquake load, the large C-shaped steel energy dissipation device can absorb the lateral load energy through deformation, and the friction device absorbs the longitudinal load energy through its own relative friction. The present invention is mainly used for double-column piers with tie beams in the field of bridges, which realizes the assembly, replacement and repairability of the tie beam, reduces the full life cycle cost, changes the brittle failure mode of the shear failure of the tie beam into ductile failure, enhances the seismic performance of the double-column pier, and realizes sufficient energy dissipation under earthquake action.

Description

Technical Field

[0001] The invention relates to the field of bridge engineering, and in particular to a C-shaped steel-friction damper combined energy dissipation structure and method. Background Art

[0002] With the rapid growth of my country's economic strength, the demand for transportation infrastructure is increasing, and the technical requirements for basic buildings such as roads and bridges are getting higher and higher. However, my country has a vast territory and complex terrain, especially in the southwest region, which is surrounded by high mountains and has a large difference in terrain height. It is extremely difficult to use traditional on-site construction methods, the construction period is long, and pouring concrete on site pollutes the environment. At the same time, the quality of concrete cannot be strictly guaranteed. Prefabrication and assembly technology, due to the characteristics of prefabrication in the factory and assembly on site, guarantees the quality of concrete, reduces on-site environmental pollution and pouring processes, and shortens the construction period. Therefore, prefabrication and assembly technology has begun to receive attention and development.

[0003] my country is located between the Pacific Rim seismic belt and the Eurasian seismic belt, and the fault zones are widely distributed, especially in the southwest region, which is very vulnerable to earthquake damage. The seismic performance of the bridge substructure (piers) directly determines the safety performance of the entire bridge. Therefore, for the double-column high piers in mountainous areas, it has become another research topic to achieve rapid prefabrication and assembly while ensuring their seismic performance. Double-column piers, especially double-column piers with tie beams, are usually high in height. When prefabricated and assembled, they are often divided into different segments for on-site assembly. The seismic performance of the segment connection position determines the seismic performance of the structure.

[0004] Since the tie beam has the function of improving the transverse stiffness of the bridge, increasing the lateral bearing capacity of the pier, and reducing the displacement of the pier top, and the tie beam is destroyed before the pier and consumes seismic energy, it plays the role of protecting the pier as a capacity protection component. Once the tie beam is destroyed, the double-column pier system will change, accelerating the destruction of the entire pier, and even directly affecting the safety of the entire bridge structure. Therefore, ensuring the seismic performance and sustainable working capacity of the tie beam-pier connection position has become a key and difficult issue. It is urgent to propose a tie beam-pier connection structure that can both ensure the connection performance and achieve sustainable working capacity.

[0005] There are three types of existing tie beam-pier connections. The first is a metal damper, which uses the deformation of the metal damper to generate energy dissipation and provide corresponding connection performance. This connection method is simple and easy to disassemble and assemble, but usually requires a large deformation to produce significant effects. The second is a friction damper, which uses the friction force when the materials are in contact to provide energy dissipation and connection performance. The force form is simple, but the friction force is difficult to control when the deformation is large. The third is auxiliary support, that is, the tie beam and pier are directly cast in place, and anti-buckling supports are arranged around them. The support is used to dissipate energy and provide seismic performance. However, this type of support is often arranged obliquely between the tie beam and pier connection position and the pier bottom, and the required layout space is relatively large.

[0006] Based on the above reasons, it is urgent to propose a prefabricated assembly structure of pier column-tie beam connection, which can provide sufficient bearing capacity and energy dissipation capacity while meeting the prefabrication and assembly of double-column piers with tie beams, thereby improving the overall seismic performance of the double-column piers, and at the same time, it can be quickly replaced in the event of damage, thereby achieving sustainable working capacity and promoting the development and improvement of the prefabrication and assembly technology of double-column piers. Summary of the invention

[0007] In order to effectively solve the problems of prefabrication, assembly, energy consumption and replaceability of tie beams of double-column piers with tie beams in high-intensity areas mentioned in the above technical background, the present invention proposes a C-shaped steel-friction damper combined energy-absorbing structure and design and construction method, which not only realizes the assembly of the pier column-tie beam connection position, continuous energy consumption at the connection position and replaceable tie beam segments, but also enhances the ductility of the pier column-tie beam connection position, realizes continuous energy consumption, saves construction sites, reduces the full life cycle cost of bridges, and promotes the development and improvement of prefabrication and assembly technology of double-column piers with tie beams.

[0008] The technical solution adopted by the present invention is:

[0009] A C-shaped steel-friction damper combined energy dissipation structure, the C-shaped steel-friction damper combined energy dissipation structure comprises a connecting base, a large C-shaped steel energy dissipation device and a friction device; the connecting base comprises a left connecting base and a right connecting base, the left connecting base and the right connecting base are symmetrically arranged, the large C-shaped steel energy dissipation device and the friction device are installed between the left connecting base and the right connecting base; the large C-shaped steel energy dissipation device and the friction device are fixedly connected to the pier column through the left connecting base, and the large C-shaped steel energy dissipation device and the friction device are fixedly connected to the tie beam through the right connecting base; the C-shaped steel-friction damper combined energy dissipation structure is arranged at the connecting position of the pier column and the tie beam, when subjected to seismic load, the large C-shaped steel energy dissipation device can absorb lateral load energy through deformation, and the friction device absorbs longitudinal load energy through its own relative friction.

[0010] Furthermore, the structures of the left connecting base and the right connecting base are the same, both of which include a base steel plate, a base steel plate connecting bolts, a base steel plate connecting steel bar and a connecting square steel; the base steel plate is a rectangular steel plate with a plurality of through holes arranged thereon; the base steel plate connecting steel bars are a plurality of steel bars, the number of which matches the through holes on the base steel plate, the base steel plate connecting steel bars are pre-embedded in the pier or tie beam, and the ends are exposed outside the pier or tie beam; the ends of the base steel plate connecting steel bars pass through the through holes on the base steel plate, and are threadedly connected to the base steel plate connecting bolts, and one side of the base steel plate is tightly fitted to the pier or tie beam through the base steel plate connecting bolts; the connecting square steel is fixed in the middle of the other side of the base steel plate, and the base steel plate is connected to the friction device through the connecting square steel.

[0011] Furthermore, the friction device comprises a left friction preload steel plate, a right friction preload steel plate, a small C-shaped steel, a concave side friction steel plate and a convex side friction steel plate; the outer centers of the left friction preload steel plate and the right friction preload steel plate are respectively fixedly connected to the connecting square steels of the left connecting base and the right connecting base; the concave side friction steel plate and the convex side friction steel plate are located between the left friction preload steel plate and the right friction preload steel plate, one side of the concave side friction steel plate and the convex side friction steel plate are convex-concave matching surfaces, and the other sides of the concave side friction steel plate and the convex side friction steel plate are respectively fixedly connected to the friction preload steel plate and the right friction preload steel plate; the preload force between the left friction preload steel plate and the right friction preload steel plate is controlled by a number of small C-shaped steels; the two ends of the small C-shaped steel pass through the left friction preload steel plate and the right friction preload steel plate respectively, and are fixedly connected to the left friction preload steel plate and the right friction preload steel plate by threaded small C-shaped steel anchor nuts.

[0012] Furthermore, the large C-shaped steel energy dissipation device is arranged at the top and bottom between the left connecting base and the right connecting base.

[0013] Furthermore, the large C-shaped steel energy dissipation device includes a large C-shaped steel base, a large C-shaped steel, fixing bolts and fixing nuts; the large C-shaped steel base is a rectangular strip, on which a plurality of slots are provided, and one side of the large C-shaped steel is fixedly connected to the base steel plate; the number of the large C-shaped steels is several, which are installed between two large C-shaped steel bases, and the two ends of the large C-shaped steel are located in the slots of the large C-shaped steel base; the fixing bolts pass through the large C-shaped steel base and the plurality of slots of the large C-shaped steel base, and are threadedly connected with the fixing nuts; the two ends of the large C-shaped steel located in the slots are provided with anchor holes, and are mounted on the fixing bolts through the anchor holes.

[0014] Furthermore, the opening of the large C-shaped steel faces the outside of the C-shaped steel-friction damper combined energy dissipation structure.

[0015] A design method for a C-shaped steel-friction damper combined energy dissipation structure, the method is directed to the above-mentioned C-shaped steel-friction damper combined energy dissipation structure, comprising the following steps:

[0016] Step 1, determine the type of material to be used based on the known dimensions of the piers and tie beams;

[0017] Step 2, according to the determined material type, calculate the bending bearing capacity M and shear bearing capacity V of the tie beam;

[0018] Step 3: Determine the reasonable internal force requirement M of the combined energy-absorbing structure T , Q T ;

[0019] Specifically, M. T =β×M;Q T =β×V;

[0020] In the formula, β is the internal force reduction coefficient, M and V represent the bending bearing capacity and shear bearing capacity of the concrete tie beam respectively; since the energy dissipation structure yields before the ordinary concrete section of the tie beam, it can be a number less than 1, which is determined according to the requirements of the actual project;

[0021] Step 4, determine the size of the energy-consuming component;

[0022] 1. Determine the size and quantity of large C-shaped steel:

[0023] The cross section of the large C-shaped steel is rectangular, the cross section width is b, the cross section height is h, the limit plastic bending moment that a single large C-shaped steel can withstand and the number of C-shaped steels required under the bending moment requirement is n:

[0024]

[0025] n=M T / M c ;

[0026] The vertical shear force and total shear force borne by a single large C-shaped steel are:

[0027]

[0028]

[0029] And must meet In the formula, τ u With Q cu is the shear strength of C-shaped steel material and the shear bearing capacity of the section;

[0030] 2. Determine the preload force of the friction device and the number of small C-shaped steels:

[0031] The shear force demand of the friction damper is:

[0032]

[0033] The sliding friction capacity of the friction damper is:

[0034] F = P tanθ + μP sgn [sinθ];

[0035] In the formula, R m is the curvature radius of the proposed friction steel plate; θ is the rotation displacement of the friction damper; μ is the sliding friction coefficient; sgn is the sign function, that is,

[0036]

[0037] The required preload force p of the friction damper and the number of small C-shaped steels n can be determined b for:

[0038]

[0039]

[0040] Where, T b The preload force of a single small C-shaped steel can be determined according to the design standard of high-strength bolts;

[0041] Step 5, checking the reasonable stiffness requirements of the combined energy dissipation structure;

[0042] The maximum rotation displacement requirement of the combined energy dissipation structure is as follows: θ T =β×θ c Sure;

[0043] In the formula, θ c is the maximum rotation angle of the tie beam-pier column node when the concrete tie beam yields;

[0044] According to the principle of virtual work, the maximum rotation displacement θ of the combined energy dissipation structure can be obtained:

[0045]

[0046] Where, L link is the cantilever length of the concrete tie beam; I(x) is the plastic moment of inertia of the C-shaped steel;

[0047] If θ≤θ T If the combined energy-absorbing structure stiffness meets the requirement, recalculate if the combined energy-absorbing structure stiffness does not meet the requirement.

[0048] A construction method for a C-shaped steel-friction damper combined energy dissipation structure, the method is for the above-mentioned C-shaped steel-friction damper combined energy dissipation structure, the construction steps are as follows:

[0049] Step 1: According to the load borne by the double column pier, calculate the size of the concave side friction steel plate and the convex side friction steel plate and the required preload force, calculate the required number and cross-sectional size of the large C-shaped steel and the small C-shaped steel, and the number and size parameters of the steel bars connecting the base steel plate;

[0050] Step 2: pre-process the accessories required for the C-shaped steel-friction damper combined energy dissipation structure, embed the base steel plate connecting steel bars in the pier column and tie beam, and ensure that the ends of the base steel plate connecting steel bars are exposed outside the pier column or tie beam;

[0051] Step 3: Assemble the connecting base, weld the connecting square steel to the middle position of the base steel plates of the left connecting base and the right connecting base, and weld the large C-shaped steel base to the top and bottom positions of the left connecting base and the right connecting base;

[0052] Step 4, assemble the friction device, weld the left friction preload steel plate and the right friction preload steel plate to the concave side friction steel plate and the convex side friction steel plate respectively, pass the small C-shaped steel through the left friction preload steel plate and the right friction preload steel plate, apply preload at the appropriate position with the small C-shaped steel anchor nut and tighten it;

[0053] Step 5, welding the left friction preload steel plate to the connecting square steel of the left connecting base, welding the right friction preload steel plate to the connecting square steel of the right connecting base, so that the friction device is fixedly connected to the connecting base;

[0054] Step 6: Assemble the large C-shaped steel energy dissipation device, insert the large C-shaped steel into the slot of the large C-shaped steel base, pass the fixing bolts through the large C-shaped steel base and the slot and the end of the large C-shaped steel in the slot, and tighten them with fixing nuts;

[0055] Step seven, transport the C-shaped steel-friction damper combined energy-absorbing structure to the construction site, and pass the ends of the steel bars connected to the pre-embedded base steel plate through the piers and tie beams through the through holes on the base steel plate and are threadedly connected to the base steel plate connecting bolts. The base steel plate connecting bolts make one side of the base steel plate fit tightly with the piers or tie beams.

[0056] The beneficial effects of the present invention are:

[0057] 1. The present invention proposes a C-shaped steel-friction damper combined energy dissipation structure, in which the friction device is anchored by a small C-shaped steel to provide the axial force required for friction, and the concave side friction steel plate and the convex side friction steel plate produce relative displacement to achieve the purpose of energy dissipation. For the large C-shaped steel energy dissipation device, when the earthquake action is large, the large C-shaped steel begins to yield, and the energy dissipation purpose is achieved through the yield deformation of the large C-shaped steel. A C-shaped steel-friction damper combined energy dissipation structure achieves full dissipation of seismic energy through the energy dissipation method of the C-shaped steel-friction damper combination.

[0058] 2. The C-shaped steel-friction damper combined energy-absorbing structure overcomes the technical difficulty of assembling the connection position of the pier column and tie beam of the double-column pier with tie beam, realizes the assembly of the tie beam, and helps to realize the full prefabrication and assembly of the double-column pier with tie beam. Under the action of earthquake, the C-shaped steel-friction damper combined energy-absorbing structure is destroyed before the reinforced concrete structure of the pier column segment and the tie beam segment, providing a fuse effect at the connection position of the pier column and tie beam. After the earthquake, only the same energy-absorbing structure needs to be replaced to achieve rapid repair after the earthquake. The C-shaped steel-friction damper combined energy-absorbing structure realizes the assembly, replacement and repairability of the prefabricated double-column pier with tie beam, and also reduces the full life cycle cost of the double-column pier with tie beam.

[0059] 3. Since the tie beam slenderness of the cast-in-place double-column pier with tie beam is relatively small, the actual bridge earthquake damage is often shear failure at the end of the tie beam, which is a brittle failure and cannot achieve ductile failure at the pier column tie beam connection position, which is not conducive to the overall seismic resistance of the double-column pier. The C-shaped steel-friction damper combined energy dissipation structure is used for the pier column tie beam connection position, and its failure mainly occurs at the combined energy dissipation structure position, which is a ductile failure. It is safer than the traditional cast-in-place connection, improves the sustainable working capacity of the pier column tie beam connection position, and greatly enhances the seismic performance of the pier column tie beam connection position. BRIEF DESCRIPTION OF THE DRAWINGS

[0060] Figure 1 It is the installation schematic diagram of the present invention;

[0061] Figure 2 It is a schematic diagram of the overall structure of the present invention;

[0062] Figure 3 It is a side structural schematic diagram of the present invention;

[0063] Figure 4 It is a schematic diagram of the top surface structure of the present invention;

[0064] Figure 5 It is a structural schematic diagram of the connection base of the present invention;

[0065] Figure 6 This is a schematic diagram of the split structure of the connection base of the present invention;

[0066] Figure 7 It is a structural schematic diagram of a large C-shaped steel energy dissipation device of the present invention;

[0067] Figure 8 This is a schematic diagram of the disassembled structure of the large C-shaped steel energy dissipation device of the present invention;

[0068] Fig. 9 It is a structural schematic diagram of the friction device of the present invention;

[0069] Fig.10 It is a schematic diagram of the disassembled structure of the friction device of the present invention;

[0070] Fig.11 It is a design flow chart of the present invention;

[0071] Fig.12 Calculation diagram of preload force of friction device and quantity of small C-shaped steel;

[0072] Fig.13 Check the reasonable stiffness calculation diagram of the combined energy dissipation structure;

[0073] Figure 1 —10, 1—connecting base, 2—large C-shaped steel energy dissipation device, 3—friction device, 4—left connecting base, 5—right connecting base, 6—pier, 7—tie beam, 8—base steel plate, 9—base steel plate connecting bolts, 10—base steel plate connecting steel bars, 11—connecting square steel, 12—left friction preload steel plate, 13—right friction preload steel plate, 14—small C-shaped steel, 15—concave side friction steel plate, 16—convex side friction steel plate, 17—small C-shaped steel anchor nut, 18—large C-shaped steel base, 19—large C-shaped steel, 20—fixing bolts, 21—fixing nuts, 22—slots, 23—anchor holes. DETAILED DESCRIPTION

[0074] The present invention is described below based on embodiment, but it should be noted that the present invention is not limited to this embodiment. In the detailed description of the present invention below, some specific details are described in detail. However, for the part not described in detail, those skilled in the art can also fully understand the present invention.

[0075] In addition, those skilled in the art should understand that the drawings are only provided to illustrate the purpose, features and advantages of the present invention, and the drawings are not drawn entirely according to the actual scale.

[0076] At the same time, unless the context clearly requires otherwise, the words "include", "comprises" and similar words throughout the specification and claims should be interpreted as inclusive rather than exclusive or exhaustive; that is, the meaning is "including but not limited to".

[0077] Examples of reference Figure 1 As shown in FIG. 11 , the present invention proposes a C-shaped steel-friction damper combined energy dissipation structure, which is composed of a connecting base 1, a large C-shaped steel energy dissipation device 2 and a friction device 3.

[0078] like Figure 1As shown, a C-shaped steel-friction damper combined energy dissipation structure can be arranged at the end of the tie beam 7 at the connection position between the pier column 6 and the tie beam 7, and the energy dissipation structure is connected to the main structure by connecting the base 1. It should be pointed out that the end of the tie beam 7 at the connection position between the pier column 6 and the tie beam 7 is only the best arrangement position selected for illustrating this solution, and can also be arranged at other positions in actual engineering applications.

[0079] like Figure 2 As shown in FIG. 4 , a C-shaped steel-friction damper combined energy dissipation structure comprises a connecting base 1, a large C-shaped steel energy dissipation device 2 and a friction device 3;

[0080] Specifically, the connecting base 1 includes a left connecting base 4 and a right connecting base 5, and the left connecting base 4 and the right connecting base 5 are symmetrically arranged, and the large C-shaped steel energy absorbing device 2 and the friction device 3 are installed between the left connecting base 4 and the right connecting base 5; the large C-shaped steel energy absorbing device 2 and the friction device 3 are fixedly connected to the pier 6 through the left connecting base 4, and the large C-shaped steel energy absorbing device 2 and the friction device 3 are fixedly connected to the tie beam 7 through the right connecting base 5; the C-shaped steel-friction damper combined energy absorbing structure is arranged at the connection position of the pier 6 and the tie beam 7. When subjected to seismic load, the large C-shaped steel energy absorbing device 2 can absorb lateral load energy through deformation, and the friction device 3 absorbs longitudinal load energy through its own relative friction.

[0081] This embodiment also provides a specific structure of the connection base 1, the large C-shaped steel energy dissipation device 2 and the friction device 3:

[0082] like Figure 5 As shown in FIG. 6 , the left connecting base 4 and the right connecting base 5 have the same structure, and both include a base steel plate 8, a base steel plate connecting bolt 9, a base steel plate connecting steel bar 10 and a connecting square steel 11;

[0083] Specifically, the base steel plate 8 is a rectangular steel plate with a plurality of through holes arranged thereon; the base steel plate connecting steel bars 10 are a plurality of steel bars, the base steel plate connecting steel bars 10 are high-strength steel bars, the number of which matches the through holes on the base steel plate 8, the base steel plate connecting steel bars 10 are pre-buried in the pier 6 or the tie beam 7, and the end is exposed outside the pier 6 or the tie beam 7, and the length of the embedded section of the base steel plate connecting steel bars 10 meets the anchoring length requirements specified in the specification; the end of the base steel plate connecting steel bar 10 passes through the through hole on the base steel plate 8, and is threadedly connected with the base steel plate connecting bolt 9, the base steel plate connecting bolt 9 is a high-strength bolt, and one side of the base steel plate 8 is tightly fitted with the pier 6 or the tie beam 7 through the base steel plate connecting bolt 9; the connecting square steel 11 is fixedly arranged in the middle of the other side of the base steel plate 8, and the base steel plate 8 is connected to the friction device 3 through the connecting square steel 11, so that the friction device 3 and the connecting base 1 are synergistically stressed to produce the same deformation.

[0084] The connection base 1 adopts the above structure and is arranged at the disconnected position of the tie beam 7, and is used to connect the large C-shaped steel energy dissipation device 2 and the friction device 3. When subjected to earthquake loads, the connection base 1 can be disassembled and replaced as a whole, or only part of its structure can be replaced. Its specific size is determined according to the size of the tie beam 7, the outer size should be consistent with the tie beam 7, and the thickness size can be determined according to the bending bearing capacity requirements.

[0085] like Figure 7 As shown in FIG. 8 , the friction device 3 includes a left friction preload steel plate 12, a right friction preload steel plate 13, a small C-shaped steel 14, a concave side friction steel plate 15 and a convex side friction steel plate 16;

[0086] Specifically, the outer centers of the left friction preload steel plate 12 and the right friction preload steel plate 13 are fixedly connected to the connecting square steels 11 of the left connecting base 4 and the right connecting base 5 respectively; the concave side friction steel plate 15 and the convex side friction steel plate 16 are located between the left friction preload steel plate 12 and the right friction preload steel plate 13, one side of the concave side friction steel plate 15 and the convex side friction steel plate 16 are convex-concave matching surfaces, and the other sides of the concave side friction steel plate 15 and the convex side friction steel plate 16 are respectively connected to the friction The friction preload steel plate and the right friction preload steel plate 13 are fixedly connected; the preload is controlled by a plurality of small C-shaped steels 14 between the left friction preload steel plate 12 and the right friction preload steel plate 13; the small C-shaped steel 14 is made of soft steel material, and the two ends of the small C-shaped steel 14 pass through the left friction preload steel plate 12 and the right friction preload steel plate 13 respectively, and are fixedly connected to the left friction preload steel plate 12 and the right friction preload steel plate 13 through a threaded small C-shaped steel anchor nut 17.

[0087] The preload is controlled by a number of small C-shaped steels 14 to provide the axial pressure required for friction between the concave side friction steel plate 15 and the convex side friction steel plate 16, so that the concave side friction steel plate 15 and the convex side friction steel plate 16 are always kept in a compressed state and do not separate. The purpose of setting the small C-shaped steel 14 in a C shape is to produce a certain vertical deformation to avoid direct shear damage. The friction device 3 is fixed in the middle position of the connecting base 1. When subjected to seismic loads, vertical relative movement occurs on both sides of the tie beam 7, driving the vertical relative movement between the concave side friction steel plate 15 and the convex side friction steel plate 16, and the concave side friction steel plate 15 and the convex side friction steel plate 16 absorb the longitudinal load energy consumption.

[0088] like Fig. 9 As shown in FIG. 10 , the large C-shaped steel energy dissipation device 2 is arranged at the top and bottom between the left connecting base 4 and the right connecting base 5 .

[0089] Specifically, the large C-shaped steel energy dissipation device 2 includes a large C-shaped steel base 18, a large C-shaped steel 19, a fixing bolt 20 and a fixing nut 21; the large C-shaped steel base 18 is a rectangular strip, and a plurality of slots 22 are provided on the large C-shaped steel base 18, and one side of the large C-shaped steel base 18 is fixedly connected to the base steel plate 8; the number of the large C-shaped steels 19 is a plurality of pieces, and the material of the large C-shaped steel 19 can be made of soft steel material, which can easily reach the yield point to increase the energy dissipation generated by plastic deformation, and the large C-shaped steel 19 is installed between the two large C-shaped steel bases 18, and the two ends of the large C-shaped steel 19 are located in the slots 22 of the large C-shaped steel base 18; the fixing bolt 20 passes through the large C-shaped steel base 18 and the plurality of slots 22 of the large C-shaped steel base 18, and is threadedly connected with the fixing nut 21; the two ends of the large C-shaped steel 19 located in the slots 22 are provided with anchor holes 23, and the two ends of the large C-shaped steel 19 are sleeved on the fixing bolts 20 through the anchor holes 23, and the fixing bolts 20 are high-strength bolts. The opening of the large C-shaped steel 19 faces the outside of the C-shaped steel-friction damper combined energy dissipation structure.

[0090] The large C-shaped steel energy dissipation device 2 adopts the above structure and is arranged at the top and bottom of the connection base 1 to provide the main bending bearing capacity. When subjected to a large deformation caused by an earthquake load, it can absorb the lateral load energy through deformation. The specific size of the large C-shaped steel energy dissipation device 2 is determined according to the calculation result of the bending bearing capacity of the cross section of the tie beam 7, and it is sufficient to ensure that the bending bearing capacity of the large C-shaped steel energy dissipation device 2 is consistent with that of the cross section of the tie beam 7.

[0091] In order to determine the technical parameters of the friction damper and the C-shaped steel, including size, preload, quantity, etc., the present invention proposes a design method for a C-shaped steel-friction damper combined energy dissipation structure. The method is aimed at the above-mentioned C-shaped steel-friction damper combined energy dissipation structure, and includes the following steps: Fig.11 As shown;

[0092] Step 1, determine the type of material to be used based on the known dimensions of the piers and tie beams;

[0093] Step 2, according to the determined material type, calculate the bending bearing capacity M and shear bearing capacity V of the tie beam;

[0094] Step 3: Determine the reasonable internal force requirement M of the combined energy-absorbing structure T , Q T ;

[0095] M T =β×M (1);

[0096] Q T =β×V (2);

[0097] In the formula, β is the internal force reduction coefficient, M and V represent the bending bearing capacity and shear bearing capacity of the concrete tie beam respectively; since the energy dissipation structure yields before the ordinary concrete section of the tie beam, it can be a number less than 1, which is determined according to the requirements of the actual project;

[0098] Step 4, determine the size of the energy-consuming component;

[0099] 1. Determine the size and quantity of large C-shaped steel:

[0100] The cross section of the large C-shaped steel is rectangular, the cross section width is b, the cross section height is h, the limit plastic bending moment that a single large C-shaped steel can withstand and the number of C-shaped steels required under the bending moment requirement is n:

[0101]

[0102] n=M T / M c (4);

[0103] In the formula, σ y is the yield strength of the C-type damper material.

[0104] The vertical shear force and total shear force borne by a single large C-shaped steel are:

[0105]

[0106]

[0107] Where l is the horizontal projection length of the C-type damper.

[0108] And must meet

[0109]

[0110] In the formula, τ u With Q cu is the shear strength of C-shaped steel material and the shear bearing capacity of the section;

[0111] Second, determine the preload force of the friction device and the number of small C-shaped steels: Fig.12 As shown;

[0112] The shear force demand of the friction damper is:

[0113]

[0114] The sliding friction capacity of the friction damper is:

[0115] F=P tanθ+μP sgn[sinθ] (9);

[0116] Where θ is the rotation displacement of the friction damper; μ is the sliding friction coefficient; sgn is the sign function, that is,

[0117]

[0118] The required preload force p of the friction damper and the number of small C-shaped steels n can be determined b for:

[0119]

[0120]

[0121] Where, T b It is the preload force of a single small C-shaped steel and can be determined according to the design standard of high-strength bolts.

[0122] Step 5: Check the reasonable stiffness requirements of the combined energy dissipation structure; Fig.13 Shown

[0123] In order to avoid the damage of concrete tie beams, the maximum allowable rotation displacement requirement of the combined energy dissipation structure is determined according to formula (13);

[0124] θ T =β×θ c (13);

[0125] In the formula, θ c It is the maximum rotation angle of the tie beam-pier column node when the concrete tie beam yields.

[0126] According to the principle of virtual work, the maximum rotation displacement θ of the combined energy dissipation structure can be obtained:

[0127]

[0128] Where, L link is the cantilever length of the concrete tie beam; I(x) is the plastic moment of inertia of the C-shaped steel, E represents the material elastic modulus of the C-shaped damper; M(x) is the section bending moment of the C-shaped steel.

[0129] The stiffness of the energy dissipator combined with C-shaped steel and friction damper must meet

[0130] θ≤θ T (15)

[0131] A construction method for a C-shaped steel-friction damper combined energy dissipation structure, the method is for the above-mentioned C-shaped steel-friction damper combined energy dissipation structure, the construction steps are as follows:

[0132] Step 1: According to the load borne by the double column pier, the size of the concave side friction steel plate 15 and the convex side friction steel plate 16 and the required preload force are calculated, and the required number and cross-sectional size of the large C-shaped steel 19 and the small C-shaped steel 14, as well as the number and size parameters of the base steel plate connecting steel bars are calculated;

[0133] Step 2: pre-process the accessories required for the C-shaped steel-friction damper combined energy dissipation structure, embed the base steel plate connecting steel bar 10 in the pier 6 and the tie beam 7, and ensure that the end of the base steel plate connecting steel bar 10 is exposed outside the pier 6 or the tie beam 7;

[0134] Step 3: Assemble the connecting base 1, weld the connecting square steel 11 to the middle position of the base steel plate 8 of the left connecting base 4 and the right connecting base 5, and weld the large C-shaped steel base 18 to the top and bottom positions of the left connecting base 4 and the right connecting base 5;

[0135] Step 4, assemble the friction device 3, weld the left friction preload steel plate 12 and the right friction preload steel plate 13 to the concave side friction steel plate 15 and the convex side friction steel plate 16 respectively, pass the small C-shaped steel 14 through the left friction preload steel plate 12 and the right friction preload steel plate 13, apply preload at a suitable position with the small C-shaped steel anchor nut 17 and tighten and fix;

[0136] Step 5, welding the left friction preload steel plate 12 to the connecting square steel 11 of the left connecting base 4, welding the right friction preload steel plate 13 to the connecting square steel 11 of the right connecting base 5, so that the friction device 3 is fixedly connected to the connecting base 1;

[0137] Step 6, assemble the large C-shaped steel energy dissipation device 2, insert the large C-shaped steel 19 into the slot 22 of the large C-shaped steel base 18, pass the fixing bolt 20 through the large C-shaped steel base 18 and the slot 22 and the end of the large C-shaped steel 19 in the slot 22, and tighten it with the fixing nut 21;

[0138] Step seven, transport the C-shaped steel-friction damper combined energy-absorbing structure to the construction site, and pass the end of the base steel plate connecting steel bar 10 embedded in the pier 6 and the tie beam 7 through the through hole on the base steel plate 8, and threadedly connect it with the base steel plate connecting bolt 9. The base steel plate connecting bolt 9 makes one side of the base steel plate 8 fit tightly with the pier 6 or the tie beam 7.

Claims

1. A design method for a C-shaped steel-friction damper combined energy dissipation structure, characterized in that: The method is directed to a C-shaped steel-friction damper combined energy dissipation structure; the C-shaped steel-friction damper combined energy dissipation structure comprises a connecting base, a large C-shaped steel energy dissipation device and a friction device; the connecting base comprises a left connecting base and a right connecting base, the left connecting base and the right connecting base are symmetrically arranged, and the large C-shaped steel energy dissipation device and the friction device are installed between the left connecting base and the right connecting base; the large C-shaped steel energy dissipation device and the friction device are fixedly connected to the pier column through the left connecting base, and the large C-shaped steel energy dissipation device and the friction device are fixedly connected to the tie beam through the right connecting base; the C-shaped steel-friction damper combined energy dissipation structure is arranged at the connection position of the pier column and the tie beam, and when subjected to seismic load, the large C-shaped steel energy dissipation device can absorb lateral load energy through deformation, and the friction device absorbs longitudinal load energy through its own relative friction; The friction device comprises a left friction preload steel plate, a right friction preload steel plate, a small C-shaped steel, a concave side friction steel plate and a convex side friction steel plate; the outer centers of the left friction preload steel plate and the right friction preload steel plate are respectively fixedly connected to the connecting square steels of the left connecting base and the right connecting base; the concave side friction steel plate and the convex side friction steel plate are located between the left friction preload steel plate and the right friction preload steel plate, one side of the concave side friction steel plate and the convex side friction steel plate are convex-concave matching surfaces, and the other sides of the concave side friction steel plate and the convex side friction steel plate are respectively fixedly connected to the friction preload steel plate and the right friction preload steel plate; the preload force between the left friction preload steel plate and the right friction preload steel plate is controlled by a number of small C-shaped steels; the two ends of the small C-shaped steel pass through the left friction preload steel plate and the right friction preload steel plate respectively, and are fixedly connected to the left friction preload steel plate and the right friction preload steel plate through threaded small C-shaped steel anchor nuts; The large C-shaped steel energy dissipation device is arranged at the top and bottom between the left connection base and the right connection base; The large C-shaped steel energy dissipation device comprises a large C-shaped steel base, a large C-shaped steel, a fixing bolt and a fixing nut; the large C-shaped steel base is a rectangular strip, on which a plurality of slots are arranged, and one side of the large C-shaped steel base is fixedly connected to the base steel plate; the number of the large C-shaped steels is a plurality of pieces, which are installed between two large C-shaped steel bases, and the two ends of the large C-shaped steel are located in the slots of the large C-shaped steel base; the fixing bolts pass through the large C-shaped steel base and the plurality of slots of the large C-shaped steel base, and are threadedly connected with the fixing nuts; the two ends of the large C-shaped steel located in the slots are provided with anchor holes, and the large C-shaped steel is sleeved on the fixing bolts through the anchor holes; The method comprises the following steps: Step 1, determine the type of material to be used based on the known dimensions of the piers and tie beams; Step 2, according to the determined material type, calculate the bending bearing capacity M and shear bearing capacity V of the tie beam; Step 3: Determine the reasonable internal force requirement M of the combined energy-absorbing structure T , Q T ; Specifically, M. T =β×M;Q T =β×V; In the formula, β is the internal force reduction coefficient, M and V represent the bending bearing capacity and shear bearing capacity of the concrete tie beam respectively; since the energy dissipation structure yields before the ordinary concrete section of the tie beam, a number less than 1 is taken, which is determined according to the requirements of the actual project; Step 4, determine the size of the energy-consuming component; 1. Determine the size and quantity of large C-shaped steel: The cross section of the large C-shaped steel is rectangular, the cross section width is b, the cross section height is h, the limit plastic bending moment borne by a single large C-shaped steel and the number of large C-shaped steels required under the bending moment requirement is n: n=M T / M c ; In the formula, σ y is the material yield strength of the large C-shaped steel; The vertical shear force and total shear force borne by a single large C-shaped steel are: Where, l is the horizontal projection length of the large C-shaped steel; In the formula, τ u With Q cu It is the shear strength and cross-sectional shear capacity of large C-shaped steel materials; Second, determine the preload force of the friction device and the number of small C-shaped steels: The shear force requirement of the friction device is: The sliding friction capacity of the friction device is: F = Ptanθ + μPsgn[sinθ]; Where θ is the rotation displacement of the friction damper; μ is the sliding friction coefficient; sgn is the sign function, that is, Determine the required preload force p of the friction device and the number of small C-shaped steels n b for: Where, T b The preload force of a single small C-shaped steel is determined according to the design standard of high-strength bolts; Step 5, checking the reasonable stiffness requirements of the combined energy dissipation structure; The maximum rotation displacement requirement of the combined energy dissipation structure is as follows: θ T =β×θ c Sure; In the formula, θ c is the maximum rotation angle of the tie beam-pier column node when the concrete tie beam yields; According to the principle of virtual work, the maximum rotation displacement θ of the combined energy dissipation structure is obtained: Where, L link is the cantilever length of the concrete tie beam; I(x) is the plastic moment of inertia of the large C-shaped steel, E represents the material elastic modulus of the large C-shaped steel; M(x) is the section bending moment of the large C-shaped steel; If θ≤θ T If the combined energy-absorbing structure stiffness meets the requirement, recalculate if the combined energy-absorbing structure stiffness does not meet the requirement.

2. The design method of the C-shaped steel-friction damper combined energy dissipation structure according to claim 1 is characterized in that: The left connecting base and the right connecting base have the same structure, both of which include a base steel plate, a base steel plate connecting bolts, a base steel plate connecting steel bar and a connecting square steel; the base steel plate is a rectangular steel plate with a plurality of through holes arranged thereon; the base steel plate connecting steel bars are a plurality of steel bars, the number of which matches the through holes on the base steel plate, the base steel plate connecting steel bars are pre-buried in the pier or tie beam, and the ends are exposed outside the pier or tie beam; the ends of the base steel plate connecting steel bars pass through the through holes on the base steel plate, and are threadedly connected to the base steel plate connecting bolts, and one side of the base steel plate is tightly fitted to the pier or tie beam through the base steel plate connecting bolts; the connecting square steel is fixedly arranged in the middle of the other side of the base steel plate, and the base steel plate is connected to the friction device through the connecting square steel.

3. The design method of the C-shaped steel-friction damper combined energy dissipation structure according to claim 1 is characterized in that: The opening of the large C-shaped steel faces the outside of the C-shaped steel-friction damper combined energy dissipation structure.

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