CN113802455B - Anchor device for carbon fiber parallel inhaul cable and anchoring method thereof - Google Patents

Abstract

An anchorage device for a carbon fiber parallel inhaul cable and an anchoring method thereof. The invention belongs to the field of engineering material CFRP application. The invention aims to solve the technical problem that the anchoring efficiency is low because a rod body is damaged due to uneven stress distribution of an anchoring area of the conventional CFRP inhaul cable anchoring system. The anchorage device of the carbon fiber reinforced composite material inhaul cable comprises an anchor cup, a front end wire splitting plate, a rear end wire splitting plate and a sealing bolt, wherein the sealing bolt is in threaded connection with the inner diameter of the tail end of the anchor cup, the anchor cup is of an integrated structure consisting of a front end straight section, a middle straight conical section and a rear end triangular groove section, the inner cavity of the front end straight section is cylindrical, the inner cavity of the middle straight conical section is in a circular truncated cone shape, and the inner cavity of the rear end triangular groove section is in a tower-shaped circular truncated cone shape. The anchor device adopts the mutual matching of the straight conical section and the triangular groove section, reduces the stress concentration at the front part, increases the anchoring effect at the rear part of the anchoring area, can improve the anchoring efficiency, and reduces the probability of rod body damage, thereby achieving higher bearing capacity.

Description

Anchoring device for carbon fiber parallel cable and anchoring method thereof

technical field

The invention belongs to the field of anchoring of carbon fiber reinforced composite materials, and particularly relates to an anchor for carbon fiber parallel cables and an anchoring method thereof.

Background technique

Since the beginning of the new century, the durability problem of bridges due to steel corrosion has become increasingly serious, and the corrosion of steel bars or steel has become the primary reason affecting the durability of concrete structures. In 2014, the total cost of corrosion in my country exceeded 2 trillion yuan, accounting for about 3.34% of the GDP in that year, of which the corrosion loss related to bridge engineering accounted for a considerable proportion. The durability and safety of infrastructure such as bridges are particularly problematic in the harsh environments of the ocean and the Midwest. Therefore, it is of great significance to solve the corrosion problem of steel bars or steel in bridge engineering, improve the durability of the structure and prolong its service life.

Relevant scientific research and engineering practice at home and abroad show that carbon fiber reinforced composite materials, as a new high-performance material, have a very broad application prospect in bridge engineering. Carbon fiber material is formed by mixing carbon fiber fiber and matrix in a certain proportion and compounding by pultrusion process. It has excellent characteristics such as light weight, high strength, corrosion resistance and fatigue resistance. Carbon fiber rods can replace ordinary steel bars, prestressed steel bars or steel cables for new bridges;

In order to give full play to the high-strength performance of carbon fiber reinforced composite rods, it must be anchored by a reliable and efficient anchoring system. Traditional steel strands are mostly anchored in the form of clips or extrusions. High and isotropic, so clip anchors or extrusion anchors can be used for steel strands, but carbon fiber rods are anisotropic and have poor lateral performance. Traditional anchoring methods will cause greater damage to carbon fiber rods. , causing the rod body to lose its bearing capacity in advance. For this reason, adhesive anchoring is mostly used for the anchoring of carbon fiber cables.

In the bonded anchor system, the inner conical anchoring form is the main form, but the inner conical anchoring form has obvious shortcomings. Because the inner conical anchoring system often occurs at the load end, that is, the cone mouth, the stress concentration occurs, resulting in the destruction of the rod body, resulting in The anchoring efficiency is low, and it is prone to fatigue damage when subjected to fatigue loads, which cannot give full play to the excellent fatigue performance of the carbon fiber rod. Secondly, the stress of the inner cone anchorage is mostly concentrated in the front, and the rear part of the anchoring area plays a very small role, so As a result, the front stress level is high and the force is unreasonable. There are also some anchoring methods that reduce the stress concentration by replacing the filling material with fillers with different stiffnesses. However, this type of anchoring method is difficult to manufacture and difficult to control. The quality of the filling material.

SUMMARY OF THE INVENTION

The present invention provides an anchor for carbon fiber parallel cables and an anchoring method thereof in order to solve the technical problem of the existing CFRP cable anchor system, the non-uniform stress distribution in the anchoring area, which leads to the destruction of the rod body and the low anchoring efficiency. .

An anchor for a carbon fiber parallel cable of the present invention comprises an anchor cup, a front-end splitter plate, a rear-end splitter plate, and a sealing bolt. The sealing bolt is threadedly connected to the inner diameter of the tail end of the anchor cup, and the anchor cup is An integrated structure composed of a front-end straight section, a middle straight cone section and a rear-end triangular groove section, the inner cavity of the front-end straight section is cylindrical, the inner cavity of the middle straight cone section is truncated, and the rear The inner cavity of the end triangular groove section is in the shape of a tower-shaped truncated cone.

It is further limited that one end of the rear end splitter plate is provided with an exhaust hole communicating with the inner cavity of the anchor cup.

It is further limited that the included angles between the truncated truncated generatrix and the axis of each layer of the truncated truncated inner cavity of the rear-end triangular groove section are α ₁ , α ₂ , α ₃ . . . α _n-1 from the top of the tower to the bottom of the tower. , α _n , where n is a positive integer, and each included angle satisfies α _n-1 ≤α _n .

Further limited, the angle β between the truncated inner cavity truncated generatrix of the middle straight cone segment and the axis satisfies β<α ₁ .

It is further limited that the angle α _n between the truncated truncated generatrix of each layer and the axis of the tower-shaped truncated inner cavity of the rear-end triangular groove section changes correspondingly with the change of the design load of the anchorage.

Further limited, the front-end wire dividing plate and the rear-end wire dividing plate are respectively clamped at the front and rear ends of the anchor cup.

Further limited, the number and diameter of holes on the front-end wire dividing plate and the rear-end wire dividing plate are the same.

A kind of anchoring method for carbon fiber parallel cable of the present invention is carried out according to the following steps:

Step 1: Fix the anchor cup on the workbench, insert the carbon fiber rod into the holes on the front-end splitter plate and the rear-end splitter plate in turn, and then clamp the rear-end splitter plate on the rear end of the anchor cup to form carbon fiber cable;

Step 2: Lift the anchor cup, perpendicular to the ground, pour epoxy iron sand from the front end of the anchor cup, after the filling is completed, clamp the front end wire dividing plate at the front end port of the anchor cup, and divide the air from the rear end through continuous vibration. The exhaust holes on the plate are discharged to make the epoxy iron sand fill in the anchor cup densely, and then the sealing bolts are screwed on, heated and cured, and the anchoring is completed.

Further limited, the epoxy iron sand in step 2 is a mixture of epoxy resin and iron sand.

Further limited, the temperature of the heating and curing in step 2 is 80-150°C, and the time is 6h-24h.

The remarkable effect that the present invention has compared with the prior art:

1) The anchoring device of the present invention adopts the straight cone section and the triangular groove section to cooperate with each other, which reduces the stress concentration in the front part, increases the anchoring effect in the rear part of the anchoring area, can improve the anchoring efficiency, and reduce the probability of rod body damage, so as to achieve greater bearing capacity;

2) The anchor of the present invention can dynamically adjust the length and angle of the straight cone section and the triangular groove section according to the number of anchoring cable rods. make appropriate magnification;

3) The angle of each section in the triangular groove section of the anchor of the present invention can be changed according to the cable load and the anchoring length, so that it can be applied to carbon fiber cables of different tonnages.

4) Due to the existence of the triangular groove section, the anchor of the present invention can reduce the overall slippage of the cable body and the filling material, thereby reducing the radial deformation of the epoxy iron sand and reducing the compressive stress on the rod body;

5) The anchoring tool of the present invention spreads the carbon fiber cable body in the anchoring area by using the front and rear wire splitting plates, in a triangular shape, which increases the contact area between the carbon fiber rod and the epoxy iron sand, and makes the rod body shear along the surface. The stress is more uniform, the compressive stress received is more uniform, the stress concentration is reduced, and the anchoring efficiency is increased.

Description of drawings

Fig. 1 is the structural representation of the anchor of the present invention;

Fig. 2 is the angle schematic diagram of the straight cone section and the triangular groove section in the anchor of the present invention;

Among them, 1-anchor cup, 101-front-end straight section, 102-middle straight cone section, 103-back-end triangular groove section, 2-front-end splitter plate, 3-rear-end splitter plate, 4-sealing bolt, 5 -Vent.

Detailed ways

Embodiment 1. An anchor for carbon fiber parallel cables in this embodiment includes an anchor cup 1, a front-end wire dividing plate 2, a rear-end wire dividing plate 3, and a sealing bolt 4. The sealing bolt 4 is connected to the anchor cup 1. The inner diameter of the rear end is threaded, and the anchor cup 1 is an integral structure composed of a front straight section 101, a middle straight cone section 102 and a rear triangular groove section 103. The inner cavity of the front straight section 101 is cylindrical. The inner cavity of the middle straight cone section 102 is in the shape of a truncated cone, the inner cavity of the rear end triangular groove section 103 is in the shape of a tower-shaped truncated cone, and one end of the rear end wire dividing plate 3 is connected with the inner cavity of the anchor cup 1 The exhaust hole 5 of the rear end triangular groove section 103, the angle between the truncated truncated generatrix and the axis of each layer of the truncated truncated inner cavity of the rear end of the triangular groove section 103 is α ₁ , α ₂ , α ₃ ... from the top to the bottom of the tower. α _n-1 , α _n , where n is a positive integer, each included angle satisfies α _n-1 ≤α _n , and the included angle β between the truncated inner cavity truncated generatrix of the middle straight cone section 102 and the axis satisfies β< α ₁ , the angle α _n between the truncated truncated generatrix of each layer of the tower-shaped truncated truncated inner cavity of the rear-end triangular groove section 103 and the axis changes correspondingly with the change of the design load of the anchor, the front-end wire splitting plate 2 and the rear-end The wire dividing plates 3 are respectively clamped at the front and rear ends of the anchor cup 1 , and the number and diameter of holes on the front end wire dividing plate 2 and the rear end wire dividing plate 3 are the same.

Embodiment 2. The method of anchoring the carbon fiber parallel cable with the anchor of embodiment 1 is carried out according to the following steps:

Step 1: Fix the anchor cup 1 on the workbench, insert the carbon fiber rod 6 into the holes on the front end wire splitting plate 2 and the rear end wire dividing plate 3 in turn, and then clamp the rear end wire dividing plate 3 on the anchor cup. The rear end of 1, forming a carbon fiber cable;

Step 2: Lift the anchor cup 1, perpendicular to the ground, and pour the epoxy iron sand 7 from the front end of the anchor cup 1. The epoxy iron sand 7 is a mixture of epoxy resin and iron sand. It is located at the front end port of the anchor cup 1, and the air is discharged from the exhaust hole 5 on the rear end splitter plate 3 through constant vibration, so that the epoxy iron sand 7 is filled in the anchor cup 1 densely, and then the sealing bolt 4 is screwed on. After heating and curing, the anchoring is completed, and the other end of the carbon fiber rod is anchored in the same way.

Claims (8)

1. An anchor for a carbon fiber parallel cable, characterized in that the anchor comprises an anchor cup (1), a front-end splitter plate (2), a rear-end splitter plate (3), and a sealing bolt (4) , the sealing bolt (4) is threadedly connected with the inner diameter of the rear end of the anchor cup (1). (103) An integrated structure, the inner cavity of the front straight section (101) is cylindrical, the inner cavity of the middle straight cone section (102) is truncated, and the rear triangular groove section (103) The inner cavity is in the shape of a tower-shaped truncated truncated cone, and the angles between the truncated truncated generatrix of each layer and the axis of the rear-end triangular groove section (103) are α 1 , α 2 , α 2 , α 2 , α 1 , α 2 , α ₁ , α ₂ , α ₃ ...α _n-1 , α _n , where n is a positive integer, each included angle satisfies α _n-1 ≤α _n , the truncated inner cavity truncated generatrix of the middle straight cone segment (102) and the axis The included angle β satisfies β<α ₁ . 2. An anchor for carbon fiber parallel cables according to claim 1, wherein one end of the rear end splitter plate (3) is provided with a row that communicates with the inner cavity of the anchor cup (1). Air holes (5). 3 . An anchor for carbon fiber parallel cables according to claim 1 , wherein the rear end triangular groove section (103) is the clamp of each layer of the circular truncated busbar and the axis of the tower-shaped truncated truncated inner cavity. 4 . The angle α _n changes correspondingly with the design load of the anchorage. 4. An anchor for carbon fiber parallel cables according to claim 1, characterized in that, the front end splitter plate (2) and the rear end splitter plate (3) are respectively clamped in the anchor cup (2). 1) the front and rear ends. 5. An anchor for carbon fiber parallel cables according to claim 1, characterized in that the number of holes and the diameter of the holes on the front end splitter plate (2) and the rear end splitter plate (3) are equal to each other. same. 6. The method for anchoring the carbon fiber parallel cable by using the anchor according to any one of claims 1-5, is characterized in that, the method is carried out according to the following steps: Step 1: Fix the anchor cup (1) on the workbench, insert the carbon fiber rod (6) into the holes on the front end splitter plate (2) and the rear end splitter plate (3) in turn, and then separate the rear end The wire plate (3) is clamped at the rear end of the anchor cup (1) to form a carbon fiber cable; Step 2: Lift the anchor cup (1), perpendicular to the ground, pour the epoxy iron sand (7) from the front end of the anchor cup (1), and then clamp the front end splitter plate (2) on the anchor cup (1) after filling. At the front end port of the anchor cup (1), the air is discharged from the vent hole (5) on the rear end splitter plate (3) by continuous vibration, so that the epoxy iron sand (7) is filled in the anchor cup (1) densely, and then screw on the seal Bolts (4) are heated and cured to complete the anchoring. 7 . The method for anchoring a carbon fiber parallel cable according to claim 6 , wherein the epoxy iron sand ( 7 ) in step 2 is a mixture of epoxy resin and iron sand. 8 . 8 . The method for anchoring a carbon fiber parallel cable according to claim 6 , wherein the heating and curing temperature in step 2 is 80-150° C., and the curing time is 6h-24h. 9 .

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