A vibration-reducing glass guardrail structure and construction method for pedestrian landscape bridge

Abstract

The present invention discloses a vibration-damping glass guardrail structure and construction method for a pedestrian landscape bridge, including a glass clamp and a guardrail glass plate, etc., mainly by arranging a U-shaped lower rubber pad at the bottom end of the guardrail glass plate, and arranging a stainless steel handrail with adjustable mass at the top end, that is, the shear stiffness of the lower rubber pad can be selected and the thickness and shape of the handrail can be adjusted, so that the natural frequency of the first-order vibration mode or other low-order vibration modes of the guardrail glass plate deviates from a certain safety interval of the vibration frequency of the maximum probability of the pulsating wind load, and also avoids being close to or the same as the natural frequency of other low-order vibration modes, so that the vibration-damping glass guardrail structure of the pedestrian landscape bridge has a controllable vibration reduction effect and improves durability; at the same time, according to the characteristics of the glass structure being vulnerable to pulsating wind loads, a design calculation method is specifically proposed, with clear principles, scientific and reasonable, simple and practical. Therefore, the present invention has the advantages of simple structure, convenient construction, low cost, safety and reliability, and high durability.

Description

Technical Field

[0001] The invention relates to the field of bridge construction, in particular to a vibration-reducing glass guardrail structure for a pedestrian landscape bridge and a construction method. Background Art

[0002] Compared with other forms of urban bridges, pedestrian landscape bridges require aesthetic creation and diverse shapes to better express the spatial charm of the integration of art and structure due to their different environments, users, structural spans and load-bearing requirements. In the design of pedestrian landscape bridges, the material and structure of the guardrail are important parts of the landscape design. Transparent and bright tempered glass guardrails are highly recommended by bridge designers and play a finishing touch. However, the existing glass guardrails of pedestrian landscape bridges are fixed to steel or concrete structures by bolts or simple flexible rubber rings. The brittle glass structure has poor stability and wind vibration resistance and is easily damaged. Summary of the invention

[0003] The object of the present invention is to overcome the defects of the prior art and provide a pedestrian landscape bridge vibration reduction glass guardrail structure and construction method which has a reasonable structure, convenient construction, reliable quality, economic savings and strong wind vibration resistance.

[0004] The technical problem of the present invention is achieved through the following technical solutions:

[0005] A vibration-damping glass guardrail structure for a pedestrian landscape bridge, comprising a plurality of concave glass clamps arranged longitudinally in sequence on the edge of the bridge deck and a plurality of guardrail glass plates installed in the plurality of glass clamps, each of the glass clamps is embedded with a U-shaped lower rubber pad, the bottom end of each guardrail glass plate is inserted into the lower rubber pad in the glass clamp, and the U-shaped side walls of each lower rubber pad extend upward and are folded to both sides to form two wings, the two wings cover the top surface of the glass clamp, and sealant is pressed into all gaps where the lower rubber pad contacts the bottom end of the guardrail glass plate for firm bonding; the bridge deck A plurality of stainless steel guardrail posts are arranged in sequence along the longitudinal direction of the edge curb at the same interval, a plurality of guardrail glass panels are installed between each two adjacent guardrail posts, and a gap is reserved between each two adjacent guardrail glass panels and between the guardrail glass panels and the guardrail posts, and a handrail is installed on the top of the plurality of guardrail posts and the plurality of guardrail glass panels; the handrail is an inverted U-shaped handrail, an inverted U-shaped upper rubber pad is embedded in the inverted U-shape of the handrail, and the top of each guardrail glass panel is inserted into the upper rubber pad in the handrail, and a sealant is pressed into all gaps where the upper rubber pad contacts the top of the guardrail glass panel for bonding The vibration-damping glass guardrail of the pedestrian landscape bridge is mainly subjected to crowd thrust, basic wind load and pulsating wind load during use. The handrail is connected to multiple guardrail columns and the top of multiple guardrail glass panels, and the bottom of the guardrail glass panel is connected to the lower rubber pad, and the top of the guardrail glass panel is connected to the upper rubber pad. Under the action of pulsating wind load, three vibration dynamic models are established according to the stiffness of the guardrail column and the handrail: Mechanical model I - when the stiffness of the guardrail column and the handrail is large, the guardrail glass panel is the vibration of the elastic embedded beams at the bottom and top ends; Mechanical model II - guardrail When the column stiffness is large and the handrail stiffness is medium, the guardrail glass plate is the vibration of the beam with the bottom embedded and the top spring supported; Mechanical model III - when the guardrail column stiffness and handrail stiffness are both small, the guardrail glass plate is the vibration of the cantilever beam with the bottom embedded and the top with a mass block; The calculation principles of the three vibration dynamic models of the pedestrian landscape bridge vibration reduction glass guardrail caused by pulsating wind loads are the same. Due to different boundary conditions, the vibration modes are different. The mechanical model III is the most sensitive to the pulsating wind load vibration. Therefore, the mechanical model III is taken as an example for analysis, and the guardrail glass plate is regarded as the lower rubber pad of the bottom U shape OA Elastic embedded cantilever beam, the handrail acts as a concentrated mass block on the top of the cantilever beam of the guardrail glass plate B At, under the action of pulsating wind load, the guardrail glass panel OB Vibration is generated. According to the theory of lateral bending vibration of cantilever with equal cross section, the guardrail glass plate OB For the top B With mass block m z and bottom OA The cantilever beam with elastic embedding constraint, the bottom of the guardrail glass plate OA Elastic embedding, under the influence of fluctuating wind loadsO Bending moment M O and shear Q O Under the effect, take l The vibration analysis of the pulsating wind load on the guardrail glass plate with a width of 1.5 mm was performed. The stiffness of the guardrail column and the handrail were both small and their influence on the vibration was ignored. In order to simplify the calculation, it was assumed that OA The segment is a rigid body with a smaller length and does not bend. A If the guardrail glass panel does not move or rotate, OB General Displacement Solution for Transverse Bending Vibration w(x,t) And other calculation formulas are as follows:

[0006] Formula 1:

[0007]

[0008] Guardrail glass panel OB General Displacement Solution for Transverse Bending Vibration w(x,t) The boundary conditions are

[0009]

[0010] Formula 2:

[0011] Guardrail glass bottom OA Elastic embedded O At the corner and displacement for

[0012]

[0013] Formula 3:

[0014] Guardrail glass panel OB The modal equations for lateral bending vibration are:

[0015]

[0016] In the above formula A n , B n , C n , D n The necessary and sufficient condition for having a non-zero solution is that the determinant of the coefficients is equal to 0, that is

[0017]

[0018] The characteristic equation composed of the above coefficients is equal to 0. The guardrail glass plate is solved by numerical method. OBEigenvalues ​​of each mode shape of transverse bending vibration and natural frequency :

[0019]

[0020] Due to the natural frequency of the low-order vibration mode , especially the first-order modal natural frequency Glass panels with guardrails OB The probability of lateral bending vibration resonance caused by pulsating wind load is the highest. Through calculation and analysis, the shear stiffness of the lower rubber pad is G and top of the guardrail glass panel B Mass block m z Natural frequencies of low-order vibration modes , especially the first-order modal natural frequency The damping effect is the greatest; therefore, the shear stiffness of the lower rubber pad should be reasonably selected. G and top of the guardrail glass panel B Mass block m z The mass of the handrail, i.e. the structure of the handrail, plays a role in vibration reduction, i.e. reducing the probability of resonance of the guardrail glass panel;

[0021] Mechanical model I and mechanical model II only need to change the boundary conditions of formula 1 to obtain similar calculation formulas; similarly, the shear stiffness of the rubber pad can be reasonably selected. G And adjust the structure of the handrail to reduce vibration, that is, reduce the probability of resonance;

[0022] The meanings of the symbols in Formula 1 to Formula 3 are as follows:

[0023] ——respectively the height of the bottom of the guardrail glass plate embedded in the lower rubber pad, the height of the handrail, and the height of the guardrail glass plate OB Height and thickness of guardrail glass plate and calculated width, ;

[0024] ——Respectively the bottom of the guardrail glass plate and O The origin x Axis and OB The vibration displacement equation of the segment is: ;

[0025] ——Guardrail glass panels OB The bending stiffness and shear modulus of the lower rubber pad, ;

[0026] - the density of the guardrail glass panel, ;

[0027] ——Guardrail glass panels OB The eigenvalues ​​and natural frequencies, initial phase angles and vibration times of each order of transverse bending vibration are dimensionless. ;

[0028] ——Bottom of guardrail glass panel O The maximum reaction strength of the lower rubber pad at the location is linearly distributed. ;

[0029] ——The bottom of the guardrail glass panel OA Elastic embedded O The angle and displacement, ;

[0030] ——The bottom of the guardrail glass panel OA Elastic embedded O Shear force and bending moment at ;

[0031] - the quality of the handrails, .

[0032] The lower rubber pad is made of high-strength nitrile rubber and PVC , and phenolic resin are blended to make a high-hardness and high-modulus nitrile rubber material; the two wings on the upper part of the lower rubber pad cover the top surface of the glass clamp and are bonded with sealant; the sealant is first injected into the U-shaped groove of the lower rubber pad and then inserted into the bottom end of the guardrail glass plate to make it tightly bonded and consolidated; the width of the U-shaped groove of the lower rubber pad is 2mm to 3mm larger than the width of the guardrail glass plate and serves as the bonding gap of the sealant, and the depth of the U-shaped groove is 2mm to 3mm larger than the embedded height of the guardrail glass plate and also serves as the bonding gap of the sealant.

[0033] The handrail is an inverted U-shaped cross-section of stainless steel material. After the guardrail glass plate is installed flat and straight, it is inserted into the upper rubber pad of the handrail. The height of the upper rubber pad is 1cm to 2cm less than the depth of the U-shaped groove of the handrail. After the straightness of the guardrail glass plate meets the requirements, the 1cm to 2cm gap is sealed with sealant.

[0034] A plurality of embedded parts are arranged in sequence along the longitudinal direction on the edge curb of the bridge deck, and a concave glass clamp is welded on each embedded part. The embedded parts are steel bars and steel plates embedded in the top surface of the edge curb of the bridge deck and welded with glass clamps.

[0035] The guardrail glass plate is a laminated tempered glass, which is made of two or more layers of ordinary float glass after tempering, and the middle layer is polyvinyl butyral. PVB Film, and two or more layers of glass are bonded together through a special process of heating and high pressure.

[0036] The sealant is a bonding and sealing material for the guardrail glass plate, the upper rubber pad, the lower rubber pad and the handrail.

[0037] A construction method for a vibration-damping glass guardrail structure of a pedestrian landscape bridge comprises the following steps:

[0038] Step 1: Research, testing and design calculation

[0039] ⑴ According to the location of the pedestrian landscape bridge construction, investigate and test the basic wind load and pulsating wind load, that is, the vibration frequency parameters with the maximum probability of pulsating wind load. If there is no test data, refer to the relevant standards and specifications for the value;

[0040] (2) Formulate the dimensions of each component of the vibration-damping glass guardrail structure of the pedestrian landscape bridge and the technical indicators of the materials used;

[0041] ⑶ Calculate the natural frequency of the first-order vibration mode of the guardrail glass plate by using formula 1 to formula 3, and adjust the shear stiffness of the rubber pad material G and handrail quality , so that the natural frequency of the first-order vibration mode of the guardrail glass plate deviates from a certain safe range of the vibration frequency with the maximum probability of pulsating wind load, and also avoids being close to or the same as the natural frequency of other low-order vibration modes;

[0042] (4) Design the vibration-damping glass guardrail structure of the pedestrian landscape bridge according to the design calculation results, including determining the spacing distance of the rigid guardrail columns and the reserved gap between each guardrail glass plate;

[0043] Step 2: Make vibration-damping glass guardrail structural components

[0044] Purchase or manufacture vibration-damping glass guardrail structural components according to design drawings, and the quality meets the design requirements;

[0045] Step 3: Install guardrail posts and glass clamps

[0046] ⑴ Clean the cement slurry residue on the edge of the bridge deck and remove the rust on the embedded parts;

[0047] ⑵Install guardrail posts according to the design drawings, and the spacing, height and straightness shall meet the design requirements;

[0048] ⑶Measure and lay out the welding position of the glass clamp and the embedded parts, which should be straight and flat;

[0049] ⑷ The welding of glass clamps and embedded parts is straight, flat and firm;

[0050] Step 4: Install the guardrail glass panel

[0051] ⑴Use a sealant gun to evenly spray a layer of sealant on the top of the glass clamp where the rubber pad is to be placed;

[0052] (2) Place the lower rubber pad in the glass clamp and apply pressure to make the two wings on the upper part of the U-shaped lower rubber pad adhere to the top surface of the glass clamp;

[0053] ⑶ Use a sealant gun to inject a certain volume of sealant into the U-shaped groove of the lower rubber pad. The sealant injection volume is determined through experiments;

[0054] (4) Use a small manipulator or manually move the guardrail glass plate to insert its bottom into the lower rubber pad, squeeze it repeatedly to make it closely bonded with the sealant, and remove excess overflow sealant;

[0055] ⑸Install the multi-level guardrail glass panel between two stainless steel guardrail columns, and check the verticality and straightness of the multi-level guardrail glass panel to ensure that it meets the design requirements;

[0056] Step 5: Install the handrail

[0057] ⑴Embed the rubber pad in the handrail, move the handrail to the top of the multi-level guardrail glass plate for trial installation;

[0058] ⑵ Check the verticality and straightness of the multi-level guardrail glass plate again. If it meets the design requirements, insert the upper rubber pad of the handrail into the top of the multi-level guardrail glass plate;

[0059] ⑶ After checking that the positions of both ends of the handrail and the guardrail column are accurate, both ends of the handrail and the guardrail column are welded firmly;

[0060] (4) Use a sealant gun to inject sealant into the gap between the bottom surface of the handrail and the upper rubber pad, wipe off the dripping sealant and stick the opening with single-sided tape, and remove the single-sided tape after the sealant solidifies;

[0061] Step 6: Handover and acceptance

[0062] After completing the full-bridge vibration-damping glass guardrail structure according to the above steps and passing the inspection, submit it for acceptance.

[0063] Compared with the prior art, the present invention provides a vibration-damping glass guardrail structure for a pedestrian landscape bridge, which is mainly achieved by arranging a U-shaped lower rubber pad at the bottom of the guardrail glass plate and an adjustable stainless steel handrail at the top, that is, the shear stiffness of the lower rubber pad can be selected and the thickness and shape of the handrail can be adjusted, so that the natural frequency of the first-order vibration mode or other low-order vibration modes of the guardrail glass plate deviates from a certain safe range of the vibration frequency of the maximum probability of the pulsating wind load, and also avoids being close to or the same as the natural frequency of other low-order vibration modes, so that the vibration-damping glass guardrail structure of the pedestrian landscape bridge has a controllable vibration-damping effect and improves durability; at the same time, according to the characteristics of the glass structure being vulnerable to pulsating wind loads, a design calculation method is specifically proposed, which has clear principles, scientific and reasonable, simple and practical, and the method can also be used for the design calculation of pulsating wind loads of glass structures of high-rise building terraces, balconies or other tall structures, and has a wide range of applications. Therefore, the present invention is a vibration-damping glass guardrail structure for a pedestrian landscape bridge with simple structure, convenient construction, low cost, safety and reliability, and high durability, which, combined with the corresponding construction method, has high economic and social benefits. BRIEF DESCRIPTION OF THE DRAWINGS

[0064] Figure 1 It is a schematic diagram of the elevation structure of the present invention.

[0065] Figure 2 for Figure 1 An enlarged view of the vibration-damping glass guardrail structure.

[0066] Figure 3 Vibration calculation diagram for vibration-damping glass guardrail structure.

[0067] Figure 4 for Figure 1 Calculation diagram of vibration of lower rubber pad. DETAILED DESCRIPTION

[0068] The embodiments of the present invention will be described in detail below with reference to the above-mentioned drawings.

[0069] like Figures 1 - 4 As shown, 1. bridge deck, 11. curbstone, 12. decorative panel, 2. embedded parts, 3. glass clamps, 4. sealant, 5. lower rubber pad, 51. two wings, 6. guardrail glass panel, 7. handrail, 8. upper rubber pad.

[0070] A pedestrian landscape bridge vibration reduction glass guardrail structure and construction method, mainly related to a vibration reduction glass guardrail structure used for pedestrian landscape bridges, high-rise building terraces, balconies or other high-rise structures, and the present embodiment is as follows Figure 1 , Figure 2As shown, a vibration-damping glass guardrail structure applied to a pedestrian landscape bridge is described in detail as an example, including a plurality of concave glass clamps 3, a plurality of stainless steel guardrail columns and a multi-level guardrail glass plate 6 arranged in sequence along the longitudinal direction on the edge curb 11 of the bridge deck 1, a plurality of stainless steel guardrail columns with the same spacing, and a multi-level guardrail glass plate 6 is installed between every two adjacent guardrail columns. The multi-level guardrail glass plate is also installed in a plurality of glass clamps 3 for support. Gaps are reserved between every two adjacent guardrail glass plates 6 and between the guardrail glass plates and the guardrail columns. A handrail 7 needs to be installed on the top of the plurality of guardrail columns and the multi-level guardrail glass plates 6.

[0071] The bridge deck 1 refers to the bridge deck of a pedestrian landscape bridge made of reinforced concrete or other materials. The curb 11 is a reinforced concrete boundary stone located at the edges of both sides of the bridge deck and higher than the pedestrian bridge deck, which can be used as a basis for installing guardrail glass panels. The decorative panel 12 suspended from the outer edge of the bridge deck 1 is a refined stone thin plate, which can be used as a decorative component of the curb of the pedestrian landscape bridge deck, covering the curb 11, embedded parts 2 and part of the glass clamp 3.

[0072] There are multiple embedded parts 2 arranged in sequence along the longitudinal direction on the edge curb 11 of the bridge deck. The number of the embedded parts 2 is the same as the number of the glass clamps 3, and each embedded part 2 is correspondingly welded with a glass clamp 3. Specifically, it is composed of components such as steel bars and steel plates embedded in the top surface of the edge curb 11 of the bridge deck 1 and welded with the glass clamps 3.

[0073] The guardrail glass plate 6 is a laminated tempered glass, which is formed by tempering two or more layers of ordinary float glass, and the middle layer is polyvinyl butyral. PVB Film is a kind of safety glass that is made by bonding two or more layers of glass together through a special process of heating and high pressure. It has the characteristics of greater resistance and also has the characteristics of ordinary laminated glass. Even if the glass is shattered, the fragments will be glued together by the middle adhesive layer, which effectively prevents the fragments from breaking and ensures the safety of pedestrians.

[0074] At the same time, the installation structure of each glass clamp 3 and the guardrail glass plate 6 is as follows: a U-shaped lower rubber pad 5 is embedded in each glass clamp 3, and the bottom end of each guardrail glass plate 6 is inserted into the lower rubber pad 5 in the glass clamp 3, and the U-shaped side walls of each lower rubber pad 5 extend upward and fold to both sides to form two wings 51, which cover the top surface of the glass clamp 3, and the sealant 4 is pressed into all the gaps where the lower rubber pad 5 contacts the bottom end of the guardrail glass plate 6 for firm bonding.

[0075] Among them, the lower rubber pad 5 is made of high-strength nitrile rubber and PVCThe high-hardness and high-modulus nitrile rubber material made by blending phenolic resin has the advantages of good weather resistance, ozone resistance, high weather resistance and vibration resistance. After the two wings 51 on the upper part of the lower rubber pad 5 cover the top surface of the glass clamp 3, it is necessary to use sealant to bond it to prevent loosening and water leakage caused by structural vibration.

[0076] Pressing the sealant 4 into the gap means that the sealant is first injected into the U-shaped groove of the lower rubber pad 5 and then inserted into the bottom end of the guardrail glass plate 6 to make it tightly bonded and consolidated. The width of the U-shaped groove of the lower rubber pad 5 is 2mm to 3mm larger than the width of the guardrail glass plate 6 and serves as the bonding gap of the sealant. The depth of the U-shaped groove is 2mm to 3mm larger than the embedded height of the guardrail glass plate 6 and also serves as the bonding gap of the sealant.

[0077] The handrail 7 is an inverted U-shaped cross-section handrail made of stainless steel. After the guardrail glass plate 6 is installed flat and straight, the inverted U-shaped upper rubber pad 8 is embedded in the inverted U-shape of the handrail 7, and the top of each guardrail glass plate 6 is inserted into the upper rubber pad 8 in the handrail 7. The height of the upper rubber pad is 1cm to 2cm less than the depth of the U-shaped groove of the handrail 7. After the straightness of the guardrail glass plate 6 meets the requirements, sealant must be pressed into all gaps where the upper rubber pad 8 contacts the top of the guardrail glass plate 6 for firm bonding, that is, the gap of 1cm to 2cm is sealed with sealant.

[0078] The material used for the upper rubber pad 8 is exactly the same as that for the lower rubber pad 5, except that the upper rubber pad 8 is an inverted U-shaped shape without a two-wing structure, and the sealant 4 is a bonding and sealing material for the guardrail glass plate 6 and the upper rubber pad 8, the lower rubber pad 5, and the handrail 7, such as silicone sealant.

[0079] The forces on the vibration-damping glass guardrail of the pedestrian landscape bridge during use are mainly the thrust of the crowd, basic wind load and pulsating wind load, among which the thrust of the crowd and the basic wind load can be designed and calculated according to relevant standards and specifications; the vibration of the vibration-damping glass guardrail of the pedestrian landscape bridge caused by the pulsating wind load can be designed and calculated according to relevant standards and specifications. In addition to preventing or reducing the probability of wind vibration by optimizing the structure, it is of great significance to save project costs and improve durability.

[0080] The handrail 7 is connected to the top of multiple guardrail columns and multiple guardrail glass plates 6, and the bottom of the guardrail glass plate is connected to the lower rubber pad 5, and the top of the guardrail glass plate 6 is connected to the upper rubber pad 8. Under the action of pulsating wind load, three vibration dynamic models are established according to the stiffness of the guardrail column and the handrail 7: Mechanical model I - when the stiffness of the guardrail column and the handrail is large, the guardrail glass plate is the vibration of the elastic embedded beams at the bottom and top ends; Mechanical model II - when the stiffness of the guardrail column is large and the stiffness of the handrail is medium, the guardrail glass plate is the bottom The vibration of the beam with embedded ends and spring support at the top; Mechanical model III - when the stiffness of the guardrail column and the handrail stiffness are both small, the guardrail glass plate is a cantilever beam with embedded bottom end and mass block at the top; The calculation principle of the three vibration dynamic models of the pedestrian landscape bridge vibration reduction glass guardrail caused by pulsating wind load is the same. Due to different boundary conditions, the vibration modes are different. The mechanical model III is the most sensitive to the vibration of pulsating wind load. Therefore, the mechanical model III is taken as an example for analysis, and the guardrail glass plate is regarded as the lower rubber pad of the bottom U shape OA The elastically embedded cantilever beam, the handrail 7 acts as a concentrated mass block on the top of the cantilever beam of the guardrail glass plate 6 B At, under the action of pulsating wind load, the guardrail glass panel OB Vibration is generated. According to the theory of lateral bending vibration of cantilever with equal cross section, the guardrail glass plate OB For the top B With mass block m z and bottom OA The cantilever beam with elastic embedding constraint, the bottom of the guardrail glass plate OA Elastic embedding, under the influence of fluctuating wind loads O Bending moment M O and shear Q O Under the effect, take l The vibration analysis of the pulsating wind load on the guardrail glass plate with a width of 1.5 mm was performed. The stiffness of the guardrail column and the handrail were both small and their influence on the vibration was ignored. In order to simplify the calculation, it was assumed that OA The segment is a rigid body with a smaller length and does not bend. A If the guardrail glass panel does not move or rotate, OB General Displacement Solution for Transverse Bending Vibration w(x,t) And other calculation formulas are as follows:

[0081] Formula 1:

[0082]

[0083] Guardrail glass panel OB General Displacement Solution for Transverse Bending Vibration w(x,t) The boundary conditions are

[0084]

[0085] Formula 2:

[0086] Guardrail glass panel 6 bottom OA Elastic embedded O At the corner and displacement for

[0087]

[0088] Formula 3:

[0089] Guardrail glass panel OB The modal equations for lateral bending vibration are:

[0090]

[0091] In the above formula A n , B n , C n , D n The necessary and sufficient condition for having a non-zero solution is that the determinant of the coefficients is equal to 0, that is

[0092]

[0093] The characteristic equation composed of the above coefficients is equal to 0. The guardrail glass plate is solved by numerical method. OB Eigenvalues ​​of each mode shape of transverse bending vibration and natural frequency :

[0094]

[0095] Due to the natural frequency of the low-order vibration mode , especially the first-order modal natural frequency Glass panels with guardrails OB The probability of lateral bending vibration resonance caused by pulsating wind load is the highest. Through calculation and analysis, the shear stiffness of the lower rubber pad is G and top of the guardrail glass panel B Mass block m z Natural frequencies of low-order vibration modes , especially the first-order modal natural frequency The damping effect is the greatest; therefore, the shear stiffness of the lower rubber pad should be reasonably selected. G and guardrail glass panel 6 top B Mass block m zThe mass of the handrail, i.e. the structure of the handrail, plays a role in vibration reduction, i.e. reducing the probability of resonance of the guardrail glass panel;

[0096] Mechanical model I and mechanical model II only need to change the boundary conditions of formula 1 to obtain similar calculation formulas; similarly, the shear stiffness of the rubber pad can be reasonably selected. G And adjust the structure of the handrail to reduce vibration, that is, reduce the probability of resonance;

[0097] The meanings of the symbols in Formula 1 to Formula 3 are as follows:

[0098] ——respectively the height of the bottom end of the guardrail glass plate 6 embedded in the lower rubber pad 5, the height of the handrail 7, the height of the guardrail glass plate OB The height and thickness of the guardrail glass plate 6 and the calculated width, ;

[0099] ——respectively the bottom of the guardrail glass plate 6 and O The origin x Axis and OB The vibration displacement equation of the segment is: ;

[0100] ——Guardrail glass panels OB The bending stiffness and shear modulus of the lower rubber pad 5, ;

[0101] - the density of the guardrail glass plate 6, ;

[0102] ——Guardrail glass panels OB The eigenvalues ​​and natural frequencies, initial phase angles and vibration times of each order of transverse bending vibration are dimensionless. ;

[0103] ——Bottom of guardrail glass panel O The maximum reaction force strength of the lower rubber pad 5 at the position is linearly distributed, ;

[0104] —— respectively the bottom of the guardrail glass plate 6 OA Elastic embedded O The angle and displacement, ;

[0105] —— respectively the bottom of the guardrail glass plate 6 OA Elastic embedded O Shear force and bending moment at ;

[0106] - the mass of the armrest 7, .

[0107] The construction method of the vibration-damping glass guardrail structure of the pedestrian landscape bridge mainly includes the following steps:

[0108] Step 1: Research, testing and design calculation

[0109] ⑴ According to the location of the pedestrian landscape bridge construction, investigate and test the basic wind load and pulsating wind load, including the vibration frequency of the maximum probability of pulsating wind load and other related parameters. If there is no test data, refer to the relevant standards and specifications for the value;

[0110] (2) Formulate the dimensions of each component of the vibration-damping glass guardrail structure of the pedestrian landscape bridge and the technical indicators of the materials used;

[0111] ⑶ Calculate the natural frequency of the first-order vibration mode of the guardrail glass plate by using formula 1 to formula 3, and adjust the shear stiffness of the rubber pad material G and handrail quality , so that the natural frequency of the first-order vibration mode of the guardrail glass plate deviates from a certain safe range of the vibration frequency with the maximum probability of pulsating wind load, and also avoids being close to or the same as the natural frequency of other low-order vibration modes;

[0112] (4) Design the vibration-damping glass guardrail structure of the pedestrian landscape bridge according to the design calculation results, including determining the spacing distance of the rigid guardrail columns and the reserved gap between each guardrail glass plate;

[0113] Step 2: Make vibration-damping glass guardrail structural components

[0114] Purchase or manufacture vibration-damping glass guardrail structural components according to design drawings, and the quality meets the design requirements;

[0115] Step 3: Install guardrail posts and glass clamps

[0116] (1) Clean the cement slurry residue on the edge of the bridge deck 1 and remove the rust on the embedded parts 2;

[0117] ⑵Install guardrail posts according to the design drawings, and the spacing, height and straightness shall meet the design requirements;

[0118] ⑶Measure and lay out the welding position of the glass clamp 3 and the embedded part 2, which should be straight and flat;

[0119] ⑷ The welding of glass clamps and embedded parts is straight, flat and firm;

[0120] Step 4: Install the guardrail glass panel

[0121] (1) Use a sealant gun to evenly spray a layer of sealant 4 on the top of the glass clamp 3 where the rubber pad 5 is to be placed;

[0122] (2) Place the lower rubber pad 5 in the glass clamp, and apply pressure to make the two wings 51 on the upper part of the U-shaped lower rubber pad adhere to the top surface of the glass clamp 3;

[0123] (3) Inject a certain volume of sealant into the U-shaped groove of the lower rubber pad 5 with a sealant gun. The sealant injection volume is determined by experiment;

[0124] (4) A small manipulator or a manual operator moves the guardrail glass plate 6 and inserts its bottom end into the lower rubber pad 5, repeatedly squeezes it to make it closely bonded with the sealant, and removes excess overflowed sealant;

[0125] ⑸Install the multi-level guardrail glass panel between two stainless steel guardrail columns, and check the verticality and straightness of the multi-level guardrail glass panel to ensure that it meets the design requirements;

[0126] Step 5: Install the handrail

[0127] (1) The upper rubber pad 8 is embedded in the handrail, and the handrail 7 is moved to the top of the multi-level guardrail glass plate 6 for trial installation;

[0128] (2) Check the verticality and straightness of the multi-level guardrail glass plate again. If it meets the design requirements, insert the upper rubber pad 8 of the handrail 7 into the top of the multi-level guardrail glass plate 6;

[0129] ⑶ After checking that the positions of both ends of the handrail and the guardrail column are accurate, both ends of the handrail 7 are welded firmly to the guardrail column;

[0130] (4) Use a sealant gun to inject sealant into the gap between the bottom surface of the handrail and the upper rubber pad, wipe off the dripping sealant and stick the opening with single-sided tape, and remove the single-sided tape after the sealant solidifies;

[0131] Step 6: Handover and acceptance

[0132] After completing the full-bridge vibration-damping glass guardrail structure according to the above steps and passing the inspection, submit it for acceptance.

[0133] The above description is only a specific embodiment of the present invention. Those skilled in the art should understand that any structural design similar to this embodiment should be included in the protection scope of the present invention.

Claims

1. A vibration-damping glass guardrail structure for a pedestrian landscape bridge, comprising a plurality of concave glass clips (3) arranged in sequence along the longitudinal direction on the edge kerb (11) of a bridge deck (1) and a multi-level guardrail glass plate (6) installed in the plurality of glass clips, characterized in that A U-shaped lower rubber pad (5) is embedded in each of the glass clamps (3), and the bottom end of each guardrail glass plate (6) is inserted into the lower rubber pad (5) in the glass clamp (3), and the U-shaped side walls of each lower rubber pad (5) extend upward and are folded to both sides to form two wings (51), which cover the top surface of the glass clamp (3), and the sealant (4) is pressed into all gaps where the lower rubber pad (5) contacts the bottom end of the guardrail glass plate (6) for firm bonding; a plurality of stainless steel guardrail columns with the same spacing are arranged in sequence along the longitudinal direction on the edge curb (11) of the bridge deck (1), and each adjacent A plurality of guardrail glass plates (6) are installed between two guardrail columns, and a gap is reserved between each two adjacent guardrail glass plates (6) and between the guardrail glass plates and the guardrail columns. A handrail (7) is installed on the top of the plurality of guardrail columns and the plurality of guardrail glass plates (6); the handrail (7) is an inverted U-shaped handrail, and an inverted U-shaped upper rubber pad (8) is embedded in the inverted U-shape of the handrail, and the top of each guardrail glass plate (6) is inserted into the upper rubber pad (8) in the handrail (7), and a sealant (4) is pressed into all gaps where the upper rubber pad (8) contacts the top of the guardrail glass plate (6) to ensure a firm bond. ; The pedestrian landscape bridge vibration reduction glass guardrail is mainly subjected to crowd thrust, basic wind load and pulsating wind load during use; the handrail (7) is connected to multiple guardrail columns and the top of multiple guardrail glass panels (6), and the bottom of the guardrail glass panel is connected to the lower rubber pad (5), and the top of the guardrail glass panel (6) is connected to the upper rubber pad (8). Under the action of pulsating wind load, three vibration dynamic models are established according to the stiffness of the guardrail column and the handrail (7): Mechanical model I - when the stiffness of the guardrail column and the handrail is large, the guardrail glass panel is the vibration of the elastic embedded beams at the bottom and top ends; Mechanical model II - when the stiffness of the guardrail column and the handrail is large, the guardrail glass panel is the vibration of the elastic embedded beams at the bottom and top ends; Mechanical model III - when the stiffness of the guardrail column and the handrail is large, the guardrail glass panel is the vibration of the elastic embedded beams at the bottom and top ends; Mechanical model III - when the stiffness of the guardrail column and the handrail is large, the guardrail glass panel is the vibration of the elastic embedded beams at the bottom and top ends; Mechanical model IV ... Model II: When the stiffness of the guardrail column is large and the stiffness of the handrail is medium, the guardrail glass plate is a vibration of a beam with a bottom embedded and a top spring support. Mechanical model III: When the stiffness of the guardrail column and the stiffness of the handrail are both small, the guardrail glass plate is a vibration of a cantilever beam with a mass block at the top and a bottom embedded. The three vibration dynamic models of the pedestrian landscape bridge vibration reduction glass guardrail caused by pulsating wind loads have the same calculation principle. Due to different boundary conditions, the vibration modes are different. The mechanical model III is the most sensitive to the vibration of pulsating wind loads. Therefore, the mechanical model III is used as an example for analysis, and the guardrail glass plate (6) is regarded as the lower rubber pad of the bottom U shape. OA The elastically embedded cantilever beam, the handrail (7) acts as a concentrated mass block on the top of the cantilever beam of the guardrail glass plate B At, under the action of pulsating wind load, the guardrail glass panel OB Vibration is generated. According to the theory of lateral bending vibration of cantilever with equal cross section, the guardrail glass plate OB For the top B With mass block m z and bottom OA The cantilever beam is elastically embedded and constrained, and the bottom of the guardrail glass plate (6) OA Elastic embedding, under the influence of fluctuating wind loads O Bending moment M O and shear Q O Under the effect, take l The vibration analysis of the pulsating wind load on the guardrail glass plate with a width of 200 mm was carried out. The stiffness of the guardrail column and the handrail (7) were both small and their influence on the vibration was ignored. In order to simplify the calculation, it was assumed that OA The segment is a rigid body with a smaller length and does not bend. A If the guardrail glass panel does not move or rotate, OB General Displacement Solution for Transverse Bending Vibration w(x,t) And other calculation formulas are as follows: Formula 1: Guardrail glass panel OB General Displacement Solution for Transverse Bending Vibration w(x,t) The boundary conditions are Formula 2: Guardrail glass panel (6) bottom OA Elastic embedded O At the corner and displacement for Formula 3: Guardrail glass panel OB The modal equations for lateral bending vibration are: In the above formula A n , B n , C n , D n The necessary and sufficient condition for having a non-zero solution is that the determinant of the coefficients is equal to 0, that is The characteristic equation composed of the above coefficients is equal to 0. The guardrail glass plate is solved by numerical method. OB Eigenvalues ​​of each mode shape of transverse bending vibration and natural frequency : Due to the natural frequency of the low-order vibration mode , especially the first-order modal natural frequency Glass panels with guardrails OB The probability of lateral bending vibration resonance caused by pulsating wind load is the highest. Through calculation and analysis, the shear stiffness of the lower rubber pad is G and top of the guardrail glass panel B Mass block m z Natural frequencies of low-order vibration modes , especially the first-order modal natural frequency The damping effect is the greatest; therefore, the shear stiffness of the lower rubber pad should be reasonably selected. G and top of the guardrail glass panel B Mass block m z The mass of the handrail, i.e. the structure of the handrail, plays a role in vibration reduction, i.e. reduces the probability of resonance of the guardrail glass plate (6); Mechanical model I and mechanical model II only need to change the boundary conditions of formula 1 to obtain similar calculation formulas; similarly, the shear stiffness of the lower rubber pad (5) can be reasonably selected. G and adjusting the structure of the handrail (7) to achieve a vibration reduction effect, i.e., reduce the probability of resonance; The meanings of the symbols in Formula 1 to Formula 3 are as follows: ——respectively the height of the bottom of the guardrail glass plate (6) embedded in the lower rubber pad (5), the height of the handrail (7), the height of the guardrail glass plate OB The height and thickness of the guardrail glass plate (6) and the calculated width, ; ——respectively the bottom of the guardrail glass plate (6) and O The origin x Axis and OB The vibration displacement equation of the segment is: ; ——Guardrail glass panels OB The flexural rigidity and shear modulus of the lower rubber pad (5), ; - density of the guardrail glass sheet (6), ; ——Guardrail glass panels OB The eigenvalues ​​and natural frequencies, initial phase angles and vibration times of each order of transverse bending vibration are dimensionless. ; ——Bottom of guardrail glass panel (6) O The maximum reaction strength of the lower rubber pad (5) at the position is linearly distributed, ; —— respectively, the bottom of the guardrail glass plate (6) OA Elastic embedded O The angle and displacement, ; —— respectively, the bottom of the guardrail glass plate (6) OA Elastic embedded O Shear force and bending moment at ; - the mass of the handrail (7), .

2. The vibration-damping glass guardrail structure for a pedestrian landscape bridge according to claim 1 is characterized in that The lower rubber pad (5) is made of high-strength nitrile rubber and PVC , phenolic resin and a high-hardness, high-modulus nitrile rubber material; the two wings (51) on the upper part of the lower rubber pad (5) cover the top surface of the glass clamp (3) and are bonded with a sealant; the sealant is first injected into the U-shaped groove of the lower rubber pad (5) and then inserted into the bottom end of the guardrail glass plate (6) to make it tightly bonded and consolidated; the width of the U-shaped groove of the lower rubber pad (5) is 2 mm to 3 mm larger than the width of the guardrail glass plate (6) and serves as a bonding gap for the sealant, and the depth of the U-shaped groove is 2 mm to 3 mm larger than the embedded height of the guardrail glass plate (6) and also serves as a bonding gap for the sealant.

3. The vibration-damping glass guardrail structure for a pedestrian landscape bridge according to claim 1 is characterized in that The handrail (7) is made of stainless steel with an inverted U-shaped cross section. After the guardrail glass plate (6) is installed flat and straight, it is inserted into the upper rubber pad (8) of the handrail. The height of the upper rubber pad is less than the depth of the U-shaped groove of the handrail (7) by 1 cm to 2 cm. After the straightness of the guardrail glass plate (6) meets the requirements, the gap of 1 cm to 2 cm is sealed with a sealant.

4. The vibration-damping glass guardrail structure for a pedestrian landscape bridge according to claim 1 is characterized in that A plurality of embedded parts (2) are arranged in sequence along the longitudinal direction on the edge curb (11) of the bridge deck (1), and a concave glass clamp (3) is welded to each embedded part. The embedded parts (2) are steel bars and steel plates embedded in the top surface of the edge curb (11) of the bridge deck (1) and welded to the glass clamp (3).

5. The vibration-damping glass guardrail structure for a pedestrian landscape bridge according to claim 1 is characterized in that The guardrail glass plate (6) is a laminated tempered glass, which is formed by tempering two or more layers of ordinary float glass and compounding them, and the middle layer is polyvinyl butyral. PVB Film, and two or more layers of glass are bonded together through a special process of heating and high pressure.

6. The vibration-damping glass guardrail structure for a pedestrian landscape bridge according to claim 1 is characterized in that The sealant (4) is a bonding and sealing material for the guardrail glass plate, the upper rubber pad, the lower rubber pad, and the handrail.

7. A construction method for a vibration-damping glass guardrail structure for a pedestrian landscape bridge according to any one of claims 1 to 6, characterized in that The construction method comprises the following steps: Step 1: Research, testing and design calculation ⑴ According to the location of the pedestrian landscape bridge construction, investigate and test the basic wind load and pulsating wind load, that is, the vibration frequency parameters with the maximum probability of pulsating wind load. If there is no test data, refer to the relevant standards and specifications for the value; (2) Formulate the dimensions of each component of the vibration-damping glass guardrail structure of the pedestrian landscape bridge and the technical indicators of the materials used; ⑶ Calculate the natural frequency of the first-order vibration mode of the guardrail glass plate by using formulas 1 to 3, and adjust the shear stiffness of the lower rubber pad (5) material G and handrail (7) quality , so that the natural frequency of the first-order vibration mode of the guardrail glass plate (6) deviates from a certain safety interval of the vibration frequency with the maximum probability of the pulsating wind load, and at the same time avoids being close to or the same as the natural frequency of other low-order vibration modes; (4) Design the vibration-damping glass guardrail structure of the pedestrian landscape bridge according to the design calculation results, including determining the spacing distance of the rigid guardrail columns and the reserved gap between each guardrail glass plate; Step 2: Make vibration-damping glass guardrail structural components Purchase or manufacture vibration-damping glass guardrail structural components according to design drawings, and the quality meets the design requirements; Step 3: Install guardrail posts and glass clamps (1) Cleaning the cement slurry residue on the edge curb (11) of the bridge deck (1) and removing the rust on the embedded parts (2); ⑵Install guardrail posts according to the design drawings, and the spacing, height and straightness shall meet the design requirements; ⑶ Measure and lay out the welding position of the glass clamp (3) and the embedded part (2), which must be straight and flat; (4) The glass clamp (3) and the embedded part (2) are welded straight, flat and firmly; Step 4: Install the guardrail glass panel (1) Use a sealant gun to evenly spray a layer of sealant on the top of the glass clamp (3) where the lower rubber pad (5) is to be placed; (2) placing a lower rubber pad (5) in the glass clamp (3), and applying pressure so that the two wings (51) on the upper part of the U-shaped lower rubber pad are bonded to the top surface of the glass clamp (3); (3) Inject a certain volume of sealant into the U-shaped groove of the lower rubber pad (5) using a sealant gun. The sealant injection volume is determined by experiment; (4) A small manipulator or a manual operator moves the guardrail glass plate (6) and inserts its bottom end into the lower rubber pad (5), repeatedly squeezes it to make it closely adhere to the sealant, and removes excess overflow sealant; (5) Install the multi-level guardrail glass plate (6) between two stainless steel guardrail columns, and check the verticality and straightness of the multi-level guardrail glass plate (6) to see if they meet the design requirements; Step 5: Install the handrail (1) The upper rubber pad (8) is embedded in the handrail (7), and the handrail is moved to the top of the multi-level guardrail glass plate (6) for trial installation; (2) Check the verticality and straightness of the multi-level guardrail glass plate (6) again. If it meets the design requirements, insert the upper rubber pad (8) of the handrail into the top of the multi-level guardrail glass plate; ⑶ After checking that the positions of both ends of the handrail (7) and the guardrail column are accurate, both ends of the handrail and the guardrail column are firmly welded; (4) Use a sealant gun to inject sealant into the gap between the bottom surface of the handrail (7) and the upper rubber pad (8), wipe off the dripping sealant and then use single-sided tape to stick the opening, and remove the single-sided tape after the sealant is cured; Step 6: Handover and acceptance After completing the full-bridge vibration-damping glass guardrail structure according to the above steps and passing the inspection, submit it for acceptance.

Images