CN111852069A - Concealed clear column head bucket arch cornice purlin self-resetting energy-consumption connecting node and method - Google Patents
Concealed clear column head bucket arch cornice purlin self-resetting energy-consumption connecting node and method Download PDFInfo
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- 238000005265 energy consumption Methods 0.000 title claims abstract description 29
- 238000000034 method Methods 0.000 title claims abstract description 24
- 229910000831 Steel Inorganic materials 0.000 claims abstract description 227
- 239000010959 steel Substances 0.000 claims abstract description 227
- 230000007246 mechanism Effects 0.000 claims description 25
- 238000003466 welding Methods 0.000 claims description 16
- 244000144730 Amygdalus persica Species 0.000 claims description 15
- 235000006040 Prunus persica var persica Nutrition 0.000 claims description 15
- 230000000694 effects Effects 0.000 claims description 10
- 238000004804 winding Methods 0.000 claims description 9
- 239000000956 alloy Substances 0.000 claims description 7
- 239000003822 epoxy resin Substances 0.000 claims description 7
- 229910000734 martensite Inorganic materials 0.000 claims description 7
- 229920000647 polyepoxide Polymers 0.000 claims description 7
- 229910052751 metal Inorganic materials 0.000 claims description 6
- 239000002184 metal Substances 0.000 claims description 6
- 230000009466 transformation Effects 0.000 claims description 6
- 239000007767 bonding agent Substances 0.000 claims description 5
- 230000008878 coupling Effects 0.000 claims description 4
- 238000010168 coupling process Methods 0.000 claims description 4
- 238000005859 coupling reaction Methods 0.000 claims description 4
- 229910001000 nickel titanium Inorganic materials 0.000 claims description 4
- 229910000952 Be alloy Inorganic materials 0.000 claims description 3
- HZEWFHLRYVTOIW-UHFFFAOYSA-N [Ti].[Ni] Chemical compound [Ti].[Ni] HZEWFHLRYVTOIW-UHFFFAOYSA-N 0.000 claims description 3
- 239000000853 adhesive Substances 0.000 claims description 3
- 230000001070 adhesive effect Effects 0.000 claims description 3
- 230000003014 reinforcing effect Effects 0.000 abstract description 22
- 230000009471 action Effects 0.000 abstract description 11
- 230000002787 reinforcement Effects 0.000 abstract description 11
- 230000035939 shock Effects 0.000 abstract description 4
- 238000009434 installation Methods 0.000 abstract description 3
- 238000010521 absorption reaction Methods 0.000 abstract description 2
- 238000002955 isolation Methods 0.000 abstract description 2
- 230000035882 stress Effects 0.000 description 16
- 239000000463 material Substances 0.000 description 9
- 229910001566 austenite Inorganic materials 0.000 description 7
- 238000010586 diagram Methods 0.000 description 6
- 239000002023 wood Substances 0.000 description 5
- 230000008859 change Effects 0.000 description 4
- 238000010276 construction Methods 0.000 description 4
- 238000006073 displacement reaction Methods 0.000 description 4
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- 238000005096 rolling process Methods 0.000 description 3
- 238000005728 strengthening Methods 0.000 description 3
- 238000004880 explosion Methods 0.000 description 2
- 230000006870 function Effects 0.000 description 2
- 239000012779 reinforcing material Substances 0.000 description 2
- 229910001285 shape-memory alloy Inorganic materials 0.000 description 2
- 238000005299 abrasion Methods 0.000 description 1
- 230000009286 beneficial effect Effects 0.000 description 1
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- 230000007797 corrosion Effects 0.000 description 1
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- E—FIXED CONSTRUCTIONS
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- E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
- E04G23/00—Working measures on existing buildings
- E04G23/02—Repairing, e.g. filling cracks; Restoring; Altering; Enlarging
- E04G23/0218—Increasing or restoring the load-bearing capacity of building construction elements
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04B—GENERAL BUILDING CONSTRUCTIONS; WALLS, e.g. PARTITIONS; ROOFS; FLOORS; CEILINGS; INSULATION OR OTHER PROTECTION OF BUILDINGS
- E04B1/00—Constructions in general; Structures which are not restricted either to walls, e.g. partitions, or floors or ceilings or roofs
- E04B1/62—Insulation or other protection; Elements or use of specified material therefor
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- E04B1/98—Protection against other undesired influences or dangers against vibrations or shocks; against mechanical destruction, e.g. by air-raids
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
- E04H9/00—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate
- E04H9/02—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate withstanding earthquake or sinking of ground
- E04H9/021—Bearing, supporting or connecting constructions specially adapted for such buildings
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- E04H—BUILDINGS OR LIKE STRUCTURES FOR PARTICULAR PURPOSES; SWIMMING OR SPLASH BATHS OR POOLS; MASTS; FENCING; TENTS OR CANOPIES, IN GENERAL
- E04H9/00—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate
- E04H9/02—Buildings, groups of buildings or shelters adapted to withstand or provide protection against abnormal external influences, e.g. war-like action, earthquake or extreme climate withstanding earthquake or sinking of ground
- E04H9/027—Preventive constructional measures against earthquake damage in existing buildings
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- E—FIXED CONSTRUCTIONS
- E04—BUILDING
- E04G—SCAFFOLDING; FORMS; SHUTTERING; BUILDING IMPLEMENTS OR AIDS, OR THEIR USE; HANDLING BUILDING MATERIALS ON THE SITE; REPAIRING, BREAKING-UP OR OTHER WORK ON EXISTING BUILDINGS
- E04G23/00—Working measures on existing buildings
- E04G23/02—Repairing, e.g. filling cracks; Restoring; Altering; Enlarging
- E04G23/0218—Increasing or restoring the load-bearing capacity of building construction elements
- E04G2023/0248—Increasing or restoring the load-bearing capacity of building construction elements of elements made of wood
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Abstract
The invention discloses a hidden type clear column head bucket arch cornice self-resetting energy-consumption connecting node and a method. The structure of the self-resetting energy-consuming connecting joint is that an outer steel pipe, an inner steel pipe, a guide rod, a left movable clamping head, a right movable clamping head, an SMA tow limiting structure and an SMA tow form a column cap bucket arch cornice self-resetting energy-consuming connecting joint. The SMA tow is driven to extend through the relative motion of the inner steel pipe and the outer steel pipe, the self-resetting of the cornice purlin under the earthquake action is realized by utilizing the hyperelasticity and the energy consumption characteristics of the SMA, the deformation of the bucket arch is reduced, the energy consumption and the shock absorption and vibration isolation capacity of the bucket arch node are enhanced, and the anti-seismic performance of the whole structure is improved. The reinforcing method has the advantages of reinforcement concealment, no influence on appearance, simple installation and small influence on other structural members.
Description
Technical Field
The invention relates to a connection node for reinforcing and repairing a wooden structure of an ancient building, in particular to a hidden type clear column head bucket arch cornice self-resetting energy-consumption connection node and a method, which can be used for reinforcing and repairing a column head bucket arch.
Background
The ancient architecture wood structure is the crystal of the Chinese architecture and has a long history. Although the wood structure has light weight and good earthquake resistance, the wood structure can still be damaged under the action of large earthquake, particularly ancient buildings in high-intensity areas, and the characteristics of aging and easy decay of wood for years can cause the structure to collapse, thereby causing great economic and cultural relic loss.
As a special component of the ancient Chinese building, the bucket arch is formed by splicing bucket and arch components in a mortise and tenon mode in a criss-cross mode, and energy consumption is mainly consumed through friction sliding and extrusion deformation among the components of each layer. The column capital science bucket arch is connected with the wooden column and is a main stress bucket arch, but under the action of a high intensity area and a great earthquake, the column capital science bucket arch is seriously damaged. In addition, as the construction time of the wooden structure of the historic building is long, part of the column heading arch is deformed and aged, and the energy consumption and shock absorption and isolation performance are seriously degraded along with the increase of the earthquake times, the strengthening of the column heading arch is of great significance.
The traditional bucket arch reinforcing position and reinforcing method mainly comprise the following steps:
(1) the reinforcing position is mainly used for reinforcing the bucket, the flat board balk and the arch.
(2) The reinforcing method comprises the steps of reinforcing the bucket arch square hopper by using angle steel, and reinforcing the large hopper and the flat plate square hopper by using superplastic alloy materials.
According to the bucket arch reinforcement method, the bucket arch anti-seismic performance can be improved, but in the bucket arch reinforcement position (1), the large bucket, the flat board arch and the arch component are small, the component is easy to damage in the reinforcement process, and actual reinforcement is difficult to operate. In the reinforcing method (2), angle steel is used for reinforcing the arch hopper, so that the appearance of the building and the current situation of cultural relics are changed; the superplastic alloy material reinforcing large bucket and flat plate balk can realize hidden reinforcement, has good energy consumption effect, is difficult to realize self-resetting, and has large residual deformation under the action of earthquake.
In view of this, it is necessary to provide a hidden type clear column head cornice self-resetting energy-consumption connecting node and a method thereof, so as to solve the problems of self-resetting and energy consumption of cornice under the action of an earthquake.
Disclosure of Invention
The invention provides a hidden type clear column head cornice self-resetting energy-consumption connecting node and a method. Meanwhile, the structure is concealed, and the appearance of the bucket arch is not changed.
The purpose of the invention is realized by the following technical scheme.
The utility model provides a clear formula column cap scientific bucket arch cornice purlin is from restoring to throne power consumption connected node, includes peach sharp roof beam, cornice purlin and cornice purlin coupling mechanism, cornice purlin is through cornice purlin coupling mechanism connection and locate peach sharp roof beam rectangle and lead to the groove.
Cornice connecting mechanism includes outer steel pipe, interior steel pipe, activity chuck and SMA silk bundle, the SMA silk bundle twines on a pair of activity chuck, and a pair of activity chuck stretch-draw SMA silk bundle is fixed including in, the spacing draw-in groove of outer steel pipe.
According to the preferable scheme, a peach sharp beam rectangular through groove is pre-opened in the peach sharp beam, the inner steel pipe is connected with the corncob and arranged in the peach sharp beam rectangular through groove, the outer steel pipe and the peach sharp beam rectangular through groove are connected through epoxy resin bonding agents, and the corncob is inserted into the inner steel pipe.
As the preferred scheme, interior steel pipe and outer steel pipe are the frame shaped plate structure, and equal open-top, spacing draw-in groove locates the both sides wall of interior steel pipe and outer steel pipe.
Preferably, the inner wall of the outer steel pipe is provided with a guide rod connected with the inner steel pipe.
Preferably, the middle of the movable chuck is a cylinder, and the end part of the movable chuck is a cuboid.
As a preferred scheme, the SMA tows wound on the pair of movable chucks are limited through an SMA tow limiting structure; the SMA tow limiting structure is a double-layer metal sheet positioned at two ends of the movable chuck, and the SMA tow is limited between the metal sheets.
Preferably, the SMA tows are made of nickel titanium or copper-aluminum-beryllium alloy materials.
Furthermore, the invention provides a hidden type clear column head bucket arch cornice self-resetting energy-consumption connecting method of the node, which comprises the following steps of:
step 1: a rectangular through groove is formed in a cornice purlin on the peach sharp beam;
step 2: stretching the movable chuck uniformly wound with the SMA tows, and clamping the movable chuck in limiting clamping grooves of left and right steel plates of the inner steel pipe;
and step 3: welding the left steel plate, the right steel plate and the bottom steel plate to form an inner steel pipe, so that the SMA tows obtain pretension;
and 4, step 4: the left steel plate and the right steel plate of the outer steel pipe are respectively arranged on the outer sides of the left steel plate and the right steel plate of the inner steel pipe, the length of the outer steel pipe is smaller than that of the inner steel pipe, and the movable chuck is clamped in the left steel plate limit clamping groove and the right steel plate limit clamping groove of the outer steel pipe;
and 5: welding a left steel plate and a right steel plate connected with a guide rod with a bottom steel plate to form an outer steel pipe;
step 6: the cornice purlin connecting mechanism is bonded with the peach sharp beam and the cornice purlin into a whole through the bonding agent.
Preferably, in the step 2, the number of winding turns of the SMA tows is changed to enable the cornice purlin connecting mechanism to obtain different restoring forces.
Preferably, in step 3, the pretension strain of the SMA wire bundle can be changed by adjusting the stroke of the test piece under the condition that the distance between the centers of the two movable chucks is not changed.
The invention has the beneficial effects that:
the invention relates to a hidden type clear column head bucket arch cornice self-resetting energy-consumption connecting node which is suitable for column head bucket arch reinforcement. Compared with the traditional reinforcing position, the reinforcing position of the invention is positioned at the cornice purlin, the displacement of the cornice purlin at the upper part of the bucket arch in the earthquake is larger than that of the large bucket at the lower part, the cornice deformation is large, and the structural safety can be better ensured by reinforcing the cornice purlin. Meanwhile, the cornice is closer to a roof, and wind blowing and sun drying are avoided, so that the reinforcing materials such as SMA tows, steel plates and epoxy resin cannot be aged and rusted.
The invention has convenient installation and simple construction. The reinforcing position is located cornice purlin department, has the disguise, does not influence building appearance after the reinforcement, can not destroy the original physiognomy of building, accords with the principle of "not changing the historical relic original state".
The reinforcing node adopts SMA tows as main energy consumption materials, and the phase change between the martensite phase and the austenite phase of the shape memory alloy material during loading and unloading is utilized to dissipate seismic energy. Compared with the friction energy consumption between the cornice truss and the cornice balk, the SMA tow energy consumption is more, and the damage of earthquake to the historic building wood structure can be effectively reduced. Meanwhile, the SMA tows have stable performance and small pre-stretching stress loss, the pre-stretching stress is basically unchanged in work, and the super-elasticity performance of the SMA tows can be effectively exerted.
When the temperature T is higher than the austenite phase transformation finishing temperature AfWhen the SMA is in an austenite phase, the self-reset energy consumption connecting node can generate stress-induced martensite phase transformation under the action of medium shock or large shock, and the material is transformed into a stress-induced martensite phase; when the external force is unloaded, the material is subjected to austenite phase change, the material is converted into an austenite phase, the material is almost free of residual deformation, the self-resetting energy consumption connection node can achieve the unique effect of self-resetting of the bucket arch, the residual deformation of the bucket arch after the earthquake is obviously reduced, and the earthquake resistance of the whole structure is optimized.
The reinforced bucket arch is in an elastic state under the action of a small earthquake, and the SMA tows do not need to be replaced and maintained after the earthquake occurs. Fatigue aging occurs after multiple earthquakes, secondary reinforcement is realized by replacing the connecting mechanism, and the energy consumption performance of the SMA tows is continuously exerted.
The restoring force of the connecting mechanism can be controlled by controlling the number of winding turns of the SMA tows, and when the number of winding turns is increased, the restoring force is increased, and the self-resetting can be achieved in a short time, so that the self-resetting and energy consumption capabilities of the bucket arch are enhanced. Under the condition that the distance between the centers of the two movable chucks is not changed, the pretensioning strain of the SMA tows can be changed by adjusting the stroke of the test piece, and the device can be suitable for various conditions.
The middle of the movable chuck is a cylinder, and the end part of the movable chuck is a cuboid. Firstly, the cylinder can reduce the friction of the SMA tows, prevent the SMA tows from being worn off, avoid stress concentration and ensure uniform stress; the end head adopts the cuboid can make the movable chuck only move between the limiting clamping grooves of the inner and outer steel pipes, thereby ensuring the normal work of the SMA tows. Meanwhile, the SMA wire bundle limiting structure on the movable chuck can limit the SMA wire bundle to work only in the range of the cylinder. Secondly, the limiting structure is larger than the limiting clamping groove of the inner steel pipe in size, so that the movable clamping head is driven to move only in parallel without rolling in the moving process of the SMA tows. In addition, the movable chuck is integrally processed by a numerical control machine tool, so that the precision is high, and the integral stress effect is good.
According to the invention, the inner steel pipe and the outer steel pipe are assembled by welding, the outer steel pipe is connected with the rectangular through groove of the peach-shaped beam, and the inner steel pipe is connected with the cornice purlin by using the epoxy resin adhesive, so that the welding and the adhesion are simple to operate, the welding strength and the adhesion strength can meet the strength requirements, and the connecting mechanism cannot be damaged firstly under the action of an earthquake.
In summary, the self-resetting energy-consuming connection node and the method for the concealed clear column head bucket arch cornice purlin of the invention have the following advantages:
1. the reinforcing method not only can consume energy, but also can realize self-resetting and has multiple functions. Meanwhile, the impact on other components is small, and the stress performance is not changed basically. In addition, the reinforcing position is located cornice purlin department for the great cornice purlin of displacement is safer, and cornice purlin is more close to the roof simultaneously, and the reinforcing material is difficult to the corrosion ageing, and the live time is longer.
2. The reinforcing method is simple in construction, does not change the appearance and the original appearance of a building, has concealment, and accords with the principle of not changing the original state of cultural relics.
And 3, the SMA filament bundle has stable performance and basically does not lose the pre-tension strain. The reinforcing node is in an elastic state under the action of small vibration, the SMA tows generate stress to induce martensite phase transformation under the action of medium vibration and large vibration, austenite phase transformation is generated after external force is eliminated, and residual deformation is small. And during secondary reinforcement, the replacement is convenient, the installation is simple, and the self-resetting energy consumption characteristic of the SMA material is continuously exerted.
4. Make cornice balk coupling mechanism obtain different restoring forces through the number of turns of control SMA silk bundle, realize fast from restoring to throne. Under the condition that the distance between the centers of the two movable chucks is not changed, the pretensioning strain of the SMA tows can be changed by adjusting the stroke of the test piece. The movable chuck has the advantages that the movable chuck is constructed to ensure that the SMA tows cannot be broken by abrasion, only does the movable chuck move in a translation mode, and is integrally processed through a numerical control machine tool, so that the precision is high.
5. The cornice purlin connecting mechanisms are connected through welding, the connecting mechanisms are bonded with the peach sharp beams and the cornice purlin, welding and bonding construction are simple, and strength is high.
Drawings
FIG. 1 is a diagram illustrating bucket arch reinforcement node positions according to an embodiment of the present invention;
FIG. 2 is an axial view of an embodiment of the present invention;
FIG. 3 is an exploded view of an outer steel tube according to an embodiment of the present invention;
FIG. 4 is an exploded view of an inner steel pipe according to an embodiment of the present invention;
FIG. 5 is a diagram of a moveable jaw and SMA strand in accordance with an embodiment of the invention;
fig. 6(a) -6(f) are schematic diagrams illustrating the operation of the embodiment of the present invention.
The reference numerals in the drawings mean: the steel tube comprises, by weight, 1-outer steel tube, 1-1-outer steel tube left steel plate, 1-2-outer steel tube right steel plate, 1-3-outer steel tube bottom steel plate, 2-inner steel tube, 2-1-inner steel tube left steel plate, 2-2-inner steel tube right steel plate, 2-3-inner steel tube bottom steel plate, 3-guide rod, 4-movable chuck, 5-SMA tow limit structure, 6-SMA tow, 7-peach top beam, 8-purlin corncob and 9-peach top beam rectangular through groove.
Detailed Description
Specific embodiments of the present invention will be described in further detail below with reference to the accompanying drawings.
As shown in fig. 1, an embodiment of the invention shows a hidden type clear column head bucket arch cornice self-resetting energy-consuming connecting node, which structurally comprises a cornice beam 7, a cornice beam 8 and a cornice connecting mechanism, wherein the cornice beam 8 is connected through the cornice beam connecting mechanism and is arranged in a rectangular through groove 9 of the cornice beam; as shown in fig. 2, the cornice purlin connecting structure includes an outer steel pipe 1, an inner steel pipe 2, a guide rod 3, a movable clamp 4, an SMA tow limiting structure 5 and an SMA tow 6. Limiting clamping grooves are formed in the left steel plate and the right steel plate of the outer steel pipe 1 and the inner steel pipe 2, and the inner steel pipe and the outer steel pipe are enabled to be overlapped. And (3) winding the hyperelastic SMA wire bundle 7 on the movable chuck 4, and stretching the movable chuck to elongate the SMA wire bundle. The movable clamp 4 is clamped in the limiting clamp grooves on the left steel plate 2-1 and the right steel plate 2-2 of the inner steel pipe, and then is welded with the bottom steel plate 2-3 of the inner steel pipe to form the inner steel pipe 2. And clamping the movable clamp 4 in the limiting clamp grooves of the left outer steel tube steel plate 1-1 and the right outer steel tube steel plate 1-2, and then welding the movable clamp with the bottom outer steel tube steel plate 1-3 to form the outer steel tube 1. The rectangular through groove 9 of the peach sharp beam is formed in the position of the 7 cornice purlin 8 of the peach sharp beam, the outer steel pipe 1 and the inner wall of the rectangular through groove 9 of the peach sharp beam are bonded through an epoxy resin bonding agent, and the inner steel pipe 2 and the cornice purlin 8 are bonded. When the cornice 8 generates rigid translation along the surface width direction, the inner steel pipe 2 and the outer steel pipe 1 are mutually staggered to drive the movable chucks 4 to move, and the SMA tows 6 are stretched along with the mutual separation of the two movable chucks 4, so that the bucket cornice self-resetting is realized by utilizing the characteristics of the shape memory alloy.
In one embodiment, the rectangular through groove of the peach-shaped beam is 110mm wide and 175mm high.
The outer steel pipe 1 and the peach-shaped beam 7 are connected by epoxy resin adhesive, and the cornice purlin 8 is inserted into the inner steel pipe 2. Interior steel pipe 2 and outer steel pipe 1 are the frame template structure, and equal open-top, the both sides wall of steel pipe 2 and outer steel pipe 1 in locating spacing draw-in groove.
Wherein, the outer steel pipe 1 and the inner steel pipe 2 are connected by 3 steel plates through fillet welds, the material is Q235 or Q345 steel, the length of the left and right steel plates of the inner steel pipe 2 is 400-700mm, the width is 100-150mm, the thickness is 3-5mm, the length of the bottom steel plate is 400-700mm, the width is 50-80mm, and the thickness is 3-5 mm; the length of the left and right steel plates of the outer steel pipe 1 is 300-600mm, the width is 120-180mm, the thickness is 3-5mm, the length of the bottom steel plate is 300-600mm, the width is 60-100mm, and the thickness is 3-5 mm. In one embodiment, the material is Q345 steel, the sizes of the left steel plate 1-1 and the right steel plate 1-2 of the outer steel pipe are 550mm multiplied by 175mm multiplied by 5mm, and the sizes of the bottom steel plate 1-3 of the outer steel pipe are 650mm multiplied by 100mm multiplied by 5 mm. The sizes of the left steel plate 2-1 and the right steel plate 2-2 of the inner steel pipe are 650mm multiplied by 150mm multiplied by 5mm, and the size of the bottom steel plate 2-3 of the inner steel pipe is 650mm multiplied by 80mm multiplied by 5 mm.
The limiting clamping grooves of the left and right steel plates of the inner and outer steel pipes are rectangular clamping grooves, the sizes of the clamping grooves of the inner and outer steel pipes are consistent, the central lines of the clamping grooves are superposed with the central lines of the left and right steel plates of the outer steel pipe, the length of each clamping groove is 40-80mm, the width of each clamping groove is 10-20mm, and the distance between the center of each clamping groove and the end part of. In one embodiment, the slot has dimensions of 50mm by 20mm, and the center of the slot is 45mm from the end of the outer steel tube.
The end part of the inner wall of the outer steel pipe 1 is provided with a guide rod 3 connected with the inner steel pipe 2, the guide rod 3 is a round steel rod made of Q235 or Q345 steel components, the diameter is 3-5mm, the length is 60-120mm, and the guide rod has the functions of preventing the inner steel pipe and the outer steel pipe from shaking and ensuring that the inner steel pipe and the outer steel pipe move horizontally along the axis when moving relatively. In one embodiment, the guide rod 3 has a diameter of 5mm and a length of 100mm, and is welded to the inner wall of the outer steel pipe 1, and the center of the guide rod is 5mm away from the end of the outer steel pipe 1.
The movable chuck 4 adopts a Q235 or Q345 steel component, the middle of the chuck is a cylinder with the diameter of 10-20mm and the length of 60-100mm, the cylinder can avoid stress concentration of SMA tows, and the stress is uniform. The two ends of the clamping head are cuboids, the side length is 15-30mm, the length is 20-25mm, and the ends of the cuboids ensure that the movable clamping heads only perform translational motion in the limiting clamping grooves of the inner steel tube and the outer steel tube, so that rolling is avoided. An SMA tow limiting structure is arranged between the end of the cuboid and the round steel bar, the limiting structure is a double-layer metal sheet made of Q235 or Q345 steel, the side length is 20-25mm, the thickness is 1-2mm, and the interval is 1-2 mm. The limiting structure ensures that the SMA tows only work in the cylindrical range of the movable chuck, so that the movable chuck only translates to prevent rolling. The movable chuck is integrally processed by a numerical control machine tool. In one embodiment, the movable chuck is made of Q345 steel, the diameter of the cylinder is 20mm, the length of the cylinder is 80mm, the side length of the end of the cuboid is 20mm, the length of the end of the cuboid is 25mm, and the double-layer metal sheets of the SMA tow limiting structure are 24mm multiplied by 5mm and are spaced at 2mm intervals.
The SMA tows 6 wound on the pair of movable chucks 4 are limited by the SMA tow limiting structure 5; the SMA tows are made of nickel titanium or copper-aluminum-beryllium alloy materials, and the diameter of the SMA tows is 1-1.5 mm. In one embodiment, the SMA wire bundle is made of nickel titanium alloy material and has a diameter of 1.2 mm.
Fig. 2 shows a self-resetting energy-consuming connection method for a hidden clear column head bucket arch cornice balk, which specifically comprises the following steps:
step 1: and a peach top beam rectangular through groove 9 is formed in the corncob beam 7 at the corncob 8 to place the corncob connecting structure.
Step 2: limiting clamping grooves are respectively formed in the left steel plate and the right steel plate of the outer steel pipe 1 and the inner steel pipe 2, and the coincidence of the clamping grooves of the inner steel pipe and the outer steel pipe is guaranteed.
And step 3: temporarily fixing the movable chuck 4, and uniformly winding the hyperelastic SMA tows 6 on the movable chuck 4. The middle of the movable chuck 4 is a cylinder, so that the friction between the SMA tows and the cylinder can be reduced, the SMA tows 6 are prevented from being worn off, stress concentration is avoided, and the stress uniformity is ensured. Both ends are cuboid ends, and the movable chuck is guaranteed to only translate between the limiting clamping grooves of the inner steel pipe and the outer steel pipe, and does not roll. Be the spacing structure of SMA silk bundle 5 between cuboid end and the cylinder, can restrict that 6 only can work at the cylinder within range of SMA silk bundle, simultaneously, the spacing structure of SMA silk bundle 5 is big than the spacing draw-in groove size of inner steel pipe, guarantees that 6 at the motion in-process of SMA silk bundle, and the parallel movement can only take place for the drive movable chuck. The whole movable chuck is processed by a numerical control machine tool, so that the precision is high, and the whole stress effect is good.
And 4, step 4: the SMA tows 6 are stretched by stretching the movable chucks 4, the movable chucks 4 are clamped in the limiting clamping grooves of the left and right steel plates of the inner steel pipe 2, and then the left and right steel plates of the inner steel pipe 2 are welded with the bottom steel plate to form the inner steel pipe 2, so that the pretension force is obtained.
The number of winding turns that can make cornice connection mechanism obtain different restoring forces through changing SMA silk bundle, and the number of SMA turns adopts the following formula to calculate:
in the formula, nmaxIs the maximum number of winding turns of SMA wire, FmaxTo the maximum load limit, A1Is the cross-sectional area of a single SMA wire,
the stress is completed for the martensitic transformation.
And 5: with the welding of guide bar 3 at 1 left and right steel sheet of outer steel pipe and end steel sheet tip, guarantee that interior steel pipe 2 can slide along the axis with outer steel pipe 1 in the relative motion in-process, avoid taking place to rock.
Under the condition that the distance between the centers of the two movable chucks is not changed, the pretensioning strain of the SMA tows can be changed by adjusting the stroke of the test piece, and the pretensioning strain is calculated by the following formula:
wherein d is the center distance of the two movable chucks and umaxIs the specimen travel, ΔmaxThe difference value of the strain and the pre-tensioning strain of the SMA wire bundle under the maximum stroke is shown, R is the radius of the movable chuck, t is the accumulated thickness of the SMA wire bundle,
is the initial pre-tension strain of the SMA wire bundle.
In one embodiment, the SMA wire bundle 6 is initially pre-tensioned to 0.6%.
Step 6: and clamping the movable clamp 4 in the limiting clamp grooves of the left and right steel plates of the outer steel pipe 1, and then welding the left and right steel plates of the outer steel pipe 1 with the bottom steel plate to form the outer steel pipe 1.
And 7: the outer steel pipe 1 and the peach-shaped beam 7 are bonded into a whole through epoxy resin bonding agents, and the inner steel pipe 2 and the cornice 8 are bonded into a whole.
In one embodiment, the bonding length of the cornice purlin and the inner steel pipe 2 is 60mm, so that the bonding strength is met.
When the cornice 8 generates rigid translation along the surface width direction, the inner steel pipe and the outer steel pipe are mutually staggered to drive the movable chuck 4 to move, and the SMA tow 6 is stretched, so that the self-resetting of the bucket cornice nodes is realized by utilizing the self-resetting energy consumption characteristic of the SMA tow.
FIG. 3 shows an explosion diagram of an outer steel pipe according to an embodiment of the present invention, in which the outer steel pipe 1 is formed by welding an outer steel pipe left steel plate 1-1, an outer steel pipe right steel plate 1-2, and an outer steel pipe bottom steel plate 1-3, and the weld joint is a fillet weld joint, which has high welding strength.
FIG. 4 shows an explosion diagram of an inner steel tube according to an embodiment of the present invention, wherein the inner steel tube 2 is formed by welding an inner steel tube left steel plate 2-1, an inner steel tube right steel plate 2-2 and an inner steel tube bottom steel plate 2-3, and the weld joint adopts a fillet weld joint, so that the welding strength is high.
Fig. 5 shows a movable clamp 4 and SMA tows 6 of an embodiment of the invention, which are uniformly wound around a cylinder of the movable clamp 4, which can reduce friction with the SMA tows.
Fig. 6(a) -6(f) show the working principle diagram of the cornice purlin connecting mechanism. The SMA tows 6 in the connecting mechanism are always in a tension state in work, when the cornice balk 8 does not move, the movable clamp 4 is located at the innermost end of the limiting clamping groove of the inner steel pipe and the outer steel pipe, the movable clamp 4 transmits the pretensioning force in the SMA tows 6 to the inner steel pipe and the outer steel pipe, and the connecting mechanism is in a self-balancing state.
When cornice 8 integrally moves rightwards, the inner and outer steel pipes are driven to move relatively, so that the right movable clamp head moves rightwards, the left movable clamp head keeps still under the restraint of the limiting clamping groove of the outer steel pipe 1, the distance between the left movable clamp head and the right movable clamp head is increased, the SMA tow 6 is gradually extended, when the cornice balice moves to a limit state, the right movable clamp head just moves to the rightmost end of the limiting clamping groove on the right side of the outer steel pipe 1, the SMA tow 6 reaches a limit tensioning state, the superelasticity characteristic of the material is exerted to the maximum extent, and the cornice 8 integrally moves leftwards to generate similar deformation.
The cornice connecting structure sequentially passes through the elastic, self-resetting and strengthening stages in the working process. In the elastic working stage, the moving distance of the cornice purlin is small, and the SMA tow 4 is in an austenite elastic deformation state. After the working stage of self-resetting, the SMA tows 6 enter the phase change stage of martensite to generate 'yield', the tensile rigidity of the SMA tows 6 is obviously reduced, and obvious tensile deformation is generated, and the cornice 8 is self-reset by the connecting mechanism, so that the earthquake damage of the bucket arch is reduced. In the strengthening stage, the displacement of the cornice purlin 8 gradually reaches the limit displacement, and the SMA tows are in the maximum stretching deformation and play the maximum self-resetting role. And finally, the movable chuck 4 becomes a shear connector between the inner steel pipe 2 and the outer steel pipe 1, shear failure occurs under the action of large earthquake shear force, and the connecting mechanism is broken and stops working.
The cornice balk connecting mechanism is arranged at the cornice balk in the bucket arch of the column head department and has concealment performance. The appearance of the reinforced bucket arch node is processed through the appearance, the appearance of a building is not affected, the energy consumption capacity and the deformation capacity of the bucket arch node are enhanced, and the anti-seismic performance of the whole structure is optimized.
The above description is only for the preferred embodiments of the present invention, but the protection scope of the present invention is not limited thereto, and any changes or substitutions that can be easily conceived by those skilled in the art within the technical scope of the present invention disclosed in the present invention should be covered within the protection scope of the present invention.
Claims (10)
1. A hidden type clean column cap bucket arch cornice self-resetting energy-consumption connecting node is characterized by comprising a cornice beam (7), a cornice beam (8) and a cornice beam connecting mechanism, wherein the cornice beam (8) is connected through the cornice beam connecting mechanism and is arranged in a rectangular through groove (9) of the cornice beam;
cornice coupling mechanism includes outer steel pipe (1), interior steel pipe (2), activity chuck (4) and SMA silk bundle (6), SMA silk bundle (6) twine on a pair of activity chuck (4), and SMA silk bundle (6) are stretched in a pair of activity chuck (4) to including fixed in the spacing draw-in groove of outer steel pipe.
2. The concealed type clear column cap scientific bucket arch cornice self-resetting energy-consumption connecting node as claimed in claim 1, wherein a cornice rectangular through groove (9) is pre-opened on a cornice beam (7), the cornice (8) is connected with the inner steel pipe (2) and is arranged in the cornice rectangular through groove (9), the outer steel pipe (1) and the cornice rectangular through groove (9) are connected through an epoxy resin adhesive, and the cornice (8) is inserted into the inner steel pipe (2).
3. The concealed clear column cap cornice self-resetting energy-consumption connecting node of claim 1, wherein the inner steel tube (2) and the outer steel tube (1) are in frame-shaped plate structures, the tops of the inner steel tube and the outer steel tube are open, and the limiting clamping grooves are formed in two side walls of the inner steel tube (2) and the outer steel tube (1).
4. The concealed clear column cap cornice self-resetting energy-consumption connecting node according to claim 1, characterized in that a guide rod (3) connected with the inner steel tube (2) is arranged on the inner wall of the outer steel tube (1).
5. The concealed clear column cap cornice self-resetting energy-consuming connecting node of claim 1, characterized in that the middle of the movable chuck (4) is a cylinder, and the end part is a cuboid.
6. The concealed clear column cap bucket arch cornice self-resetting energy-consuming connecting node of claim 1, wherein the SMA tows (6) wound on the pair of movable chucks (4) are limited by the SMA tow limiting structure (5); the SMA tow limiting structure (5) is a double-layer metal sheet positioned at two ends of the movable chuck (4), and the SMA tow (6) is limited between the metal sheets.
7. The concealed clear column cap cornice self-resetting energy-consuming connecting node as claimed in claim 1, wherein the SMA tows (6) are made of nickel titanium or copper-aluminum-beryllium alloy materials.
8. The hidden self-resetting energy-consuming connection method for the cornice of the blind column head bucket arch based on any one of the nodes of claims 1 to 7, is characterized by comprising the following steps of:
step 1: a peach top beam rectangular through groove (9) is formed in the cornice beam (7) and the cornice beam (8);
step 2: stretching the movable chuck (4) uniformly wound with the SMA tows (6) and clamping the movable chuck in the left and right steel plate limiting clamping grooves of the inner steel pipe (2);
and step 3: welding the left steel plate, the right steel plate and the bottom steel plate to form an inner steel pipe (2) so that the SMA tows (6) obtain pretension;
and 4, step 4: the left steel plate and the right steel plate of the outer steel pipe (1) are respectively arranged on the outer sides of the left steel plate and the right steel plate of the inner steel pipe (2), the length of the outer steel pipe (1) is smaller than that of the inner steel pipe (2), and the movable chuck (4) is clamped in the left steel plate and the right steel plate limiting clamping grooves of the outer steel pipe (1);
and 5: welding the left and right steel plates connected with the guide rods (3) with the bottom steel plate to form an outer steel pipe (1);
step 6: the cornice purlin connecting mechanism is bonded with the peach sharp beam (7) and the cornice purlin (8) into a whole through a bonding agent.
9. The self-resetting energy-consuming connection method for the concealed clear column head cornice purlin according to claim 8, wherein in the step 2, different restoring forces are obtained for the cornice connection mechanism by changing the winding turns of the SMA tow (6), and the SMA turns are calculated by adopting the following formula:
in the formula, nmaxIs the maximum number of winding turns of SMA wire, FmaxTo the maximum load limit, A1Is the cross-sectional area of a single SMA wire,
the stress is completed for the martensitic transformation.
10. The self-resetting energy-consumption connecting method for the concealed clear column head bucket arch cornice balk according to claim 8, wherein in the step 3, under the condition that the distance between the centers of the two movable chucks (4) is not changed, the pretensioning strain of the SMA tow (6) can be changed by adjusting the stroke of the test piece, and the pretensioning strain is calculated according to the following formula:
wherein d is the center distance of the two movable chucks and umaxIs the specimen travel, ΔmaxThe difference value of the strain and the pre-tensioning strain of the SMA wire bundle under the maximum stroke is shown, R is the radius of the movable chuck, t is the accumulated thickness of the SMA wire bundle,
is the initial pre-tension strain of the SMA wire bundle.
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| CN202010845624.9A CN111852069B (en) | 2020-08-20 | 2020-08-20 | Concealed self-resetting energy consumption connection node and method for bracket arch cornice of clear type column cap department |
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| CN111852069B (en) | 2024-06-04 |
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