A prestressed concrete cross-web support for electrified railway contact network

Abstract

The present invention discloses a prestressed concrete transverse web type support for an electrified railway contact network, comprising ultra-high performance concrete and a plurality of arch frames, wherein the plurality of arch frames are cast in the ultra-high performance concrete from bottom to top, wherein the arch frame comprises two groups of arch structures, wherein the arch structure comprises an annular frame and two V-shaped frames, wherein the two V-shaped frames are respectively fixed at the two ends of the annular frame, and the two V-shaped frames are symmetrical about the center of the annular frame, wherein the two groups of arch structures are arranged in parallel and fixedly connected by a plurality of vertical short bars, and the central axes of the annular frames of the two groups of arch structures are both located on the same vertical line. The present invention improves the overall strength and rigidity of the transverse web type support, and evenly distributes the force, so as to control the occurrence of cracks at the source of the structural design.

Description

Technical Field

[0001] The invention relates to the technical field of electrified railway contact network line infrastructure, in particular to an electrified railway contact network prestressed concrete cross-web rod type support. Background Art

[0002] Since my country's railway construction entered the era of high-speed electrification, prestressed concrete transverse bar type pillars (hereinafter referred to as transverse bar type pillars) of electrified railway contact networks have been widely used in various domestic railway trunk lines. According to the feedback on the operating conditions of various railway lines, cracks of varying degrees have appeared in the core holes and footrest holes of some transverse bar type pillars; the causes of cracks in transverse bar type pillars are relatively complex, and the overall strength, stiffness and force distribution of transverse bar type pillars in structural design are the main factors that may cause continuous cracks. Standard TB2286.1 stipulates that the transverse bar of the pillar should not have cracks, and the number of cracks should not exceed two. However, in the natural environment, after the transverse bar pillars are eroded by temperature, humidity, rain, snow, harmful gas substances, etc., as well as the shrinkage and creep characteristics of concrete, the existing cracks will extend, and even concrete spalling and steel bar corrosion caused by crack expansion will occur, which seriously affects the quality, safety and durability of the transverse bar type pillars under normal working conditions, increases the workload of railway construction and maintenance, wastes a lot of manpower, material and financial resources, and buries hidden dangers for the safe operation of railways. Therefore, completely eliminating the cracks in the transverse web type struts is an urgent problem to be solved. Summary of the invention

[0003] The purpose of the present invention is to provide a prestressed concrete transverse rod type support for an electrified railway contact network to solve the problems existing in the above-mentioned prior art, so that the overall strength and stiffness of the transverse rod type support are improved, the force distribution is uniform, and the occurrence of cracks is controlled at the source of structural design.

[0004] To achieve the above object, the present invention provides the following solutions:

[0005] The present invention provides a prestressed concrete transverse rod type support for an electrified railway contact network, comprising ultra-high performance concrete and a plurality of arch frames, wherein the plurality of arch frames are cast in the ultra-high performance concrete from bottom to top, wherein the arch frames comprise two groups of arch structures, wherein the arch structures comprise an annular frame and two V-shaped frames, wherein the two V-shaped frames are respectively fixed at two ends of the annular frame, wherein the two V-shaped frames are symmetrical about the center of the annular frame, wherein the two groups of arch structures are arranged in parallel and fixedly connected by a plurality of vertical short ribs, and wherein the central axes of the annular frames of the two groups of arch structures are both located on the same vertical line.

[0006] Preferably, the annular frame is made of steel bars, and is composed of a straight line portion, an arc portion, a straight line portion 2 and an arc portion 2 fixedly connected end to end in sequence, the straight line portion 1 is parallel to the straight line portion 2, and the arc portion 1 and the arc portion 2 have the same diameter.

[0007] Preferably, the V-shaped frames are all made of steel bars, and the bottom of the V-shaped frames has a horizontal section, and two ends of the horizontal section are respectively fixedly connected to the straight line part one and the straight line part two.

[0008] Preferably, the horizontal section is fixed to the straight line portion one and the straight line portion two by welding.

[0009] Preferably, both wings of the V-shaped frame are provided with bending sections, the bending sections are vertically fixed with the vertical short ribs, and the bending sections of the V-shaped frames corresponding to the two groups of the arch structures share one vertical short rib.

[0010] Preferably, the strength grade of the ultra-high performance concrete is UHPC120.

[0011] Preferably, the ultra-high performance concrete is mainly composed of cement, silica fume, quartz sand, crushed stone, water, synthetic fiber and water reducer, and the mass mix ratio of cement, silica fume, quartz sand, crushed stone, water, synthetic fiber and water reducer is 1:0.07:1.31:2.69:0.32:0.17:0.01.

[0012] Preferably, an admixture is added to the ultra-high performance concrete, and the mass mix ratio of the admixture is 0.34.

[0013] Compared with the prior art, the present invention has achieved the following technical effects:

[0014] The bow structure in the present invention includes an annular frame and two V-shaped frames. The annular frame is a closed structural frame. Two groups of arch structures are fixedly connected to form an arch frame. No steel bars are arranged inside the entire arch frame, but this does not affect the strength of the arch frame. On the contrary, the application of the annular frame makes the arch frame more stable and the force distribution more uniform, thereby improving the overall strength and stiffness of the transverse rod type support and uniformly distributing the force, so as to achieve the purpose of controlling the occurrence of cracks at the source of structural design. BRIEF DESCRIPTION OF THE DRAWINGS

[0015] In order to more clearly illustrate the embodiments of the present invention or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying creative work.

[0016] Figure 1It is a schematic diagram of the external structure of the prestressed concrete cross-web type support of the electrified railway contact network of the present invention;

[0017] Figure 2 for Figure 1 Schematic diagram of the structure of the bow frame at the middle AA section;

[0018] Figure 3 for Figure 2 Side view of

[0019] Figure 4 It is a structural schematic diagram of the bow frame in the traditional electrified railway contact network prestressed concrete cross-web rod type support;

[0020] Figure 5 for Figure 4 Side view of

[0021] Among them: 1- transverse web type support, 2- pedal hole, 3- core hole, 4- V-shaped frame, 41- horizontal section, 42- bending section, 5- annular frame, 51- straight line part, 52- arc part, 53- straight line part 2, 54- arc part 2, 6- vertical short ribs, 7- longitudinal V-shaped frame, 8- transverse short ribs, 9- connecting ribs. DETAILED DESCRIPTION

[0022] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0023] In order to make the above-mentioned objects, features and advantages of the present invention more obvious and easy to understand, the present invention is further described in detail below with reference to the accompanying drawings and specific embodiments.

[0024] like Figure 1-Figure 3 As shown: This embodiment provides a prestressed concrete transverse rod type support for an electrified railway contact network, including concrete and a plurality of arch frames, the plurality of arch frames are cast in concrete from bottom to top, the arch frames include two groups of arch structures, the arch structures include an annular frame 5 and two V-shaped frames 4, the two V-shaped frames 4 are respectively fixed at both ends of the annular frame 5, the two V-shaped frames 4 are symmetrical about the center of the annular frame 5, the two groups of arch structures are arranged in parallel and fixedly connected by a plurality of vertical short ribs 6, the central axes of the annular frames 5 of the two groups of arch structures are both located on the same vertical line, from Figure 1 As can be seen from the external structure, a plurality of pedal holes 2 and core holes 3 can be provided on the transverse web type support 1.

[0025] Specifically, the annular frame 5 is composed of a straight line portion 51, an arc portion 52, a straight line portion 53 and an arc portion 54, which are fixedly connected end to end in sequence. The straight line portion 51 is parallel to the straight line portion 53, and the diameters of the arc portion 52 and the arc portion 54 are the same, thereby forming an annular frame 5 similar to a "runway". The closed structure makes the annular frame 5 more stable and the force distribution more reasonable. The bottom of the V-shaped frame 4 has a horizontal section 41, and the two ends of the horizontal section 41 are respectively fixedly connected to the straight line portion 51 and the straight line portion 53, and the horizontal section 41 is welded to the straight line portion 51 and the straight line portion 53. The horizontal section 41 is used to make the V-shaped frame 4 and the annular frame 5 fixed and welded more firmly. Both wings of the V-shaped frame 4 are provided with a bending section 42, and the bending sections 42 are vertically fixed with vertical short ribs 6. The bending sections 42 of the V-shaped frames 4 corresponding to the two groups of bow structures share a vertical short rib 6. Specifically, Figure 3 As shown, two sets of arch structures are fixed into one by vertical short bars 6. The annular frame 5 and the V-shaped frame 4 in the arch structure are made of existing steel bars, and the specific model can be reasonably selected according to the design requirements.

[0026] The strength grade of ultra-high performance concrete is UHPC120, and the ultra-high performance concrete can be any existing ultra-high performance concrete with a strength grade of UHPC120. Alternatively, the ultra-high performance concrete with a strength of 120 MPa using the following specific mix ratio scheme is mainly composed of cement, silica fume, quartz sand, crushed stone, water, synthetic fiber and water reducer. The mix ratio of cement, silica fume, quartz sand, crushed stone, water, synthetic fiber and water reducer is 1:0.07:1.31:2.69:0.32:0.17:0.01. This mass mix ratio specifically refers to the mass ratio of other components that need to be added when 1 kg of cement is added. The synthetic fiber is preferably steel fiber, which can increase the cohesion of concrete and improve the crack resistance of concrete; the added quartz sand fills the gaps in the concrete densely, improves the density of the concrete, and increases the anti-seepage capacity of the concrete; the added crushed stone increases the distribution performance and vibration molding performance of the concrete working performance, and improves the production efficiency of the concrete distributor; the added water reducer effectively controls the amount of water, reduces the water-cement ratio, and improves the strength of concrete. Admixtures are added to ultra-high performance concrete, and the mix ratio of the admixture is 0.34. The admixture can effectively reduce the amount of cement used and increase the workability of concrete. Compared with ordinary concrete, ultra-high performance concrete has ultra-high strength and toughness, high impermeability, and effectively improves the impermeability of the transverse bar type support 1, preventing the invasion of harmful substances. Even in an environment with large changes in temperature and humidity, it can effectively resist cracking and increase the service life of the transverse bar type support 1.

[0027] The traditional bow frame structure is Figure 4-Figure 5As shown, it includes three groups of arch structures, each group of arch structures includes two longitudinal V-shaped frames 7, the bottoms of the two longitudinal V-shaped frames 7 are welded and connected by two transverse short ribs 8, and the three groups of longitudinal V-shaped frames 7 are welded and fixed together by connecting ribs 9 in the vertical direction. Compared with the traditional arch frame, the annular frame 5 of the present invention is a closed structure frame, and the two groups of arch structures are fixedly connected to form an arch frame. There is no steel bar inside the entire arch frame, but the lack of steel bars inside does not affect the strength of the arch frame. On the contrary, the application of the annular frame 5 makes the arch frame more stable and the force distribution more uniform, thereby improving the overall strength and rigidity of the transverse web type support, and the force distribution is uniform, so as to achieve the purpose of controlling the occurrence of cracks at the source of structural design. Moreover, due to the improvement of overall strength and rigidity, and because only two annular frames 5 are used, the diameter of the steel bars in the annular frame 5 can be increased, and the working area of ​​the steel bars in the annular frame 5 can be increased. For example, the traditional three groups of arch structures all use 5mm steel bars, while the steel bars of the two groups of arch structures in the present invention all use 8mm steel bars, and the working area of ​​the steel bars is increased by 1.7 times.

[0028] The present specification uses specific examples to illustrate the principles and implementation methods of the present invention. The above examples are only used to help understand the method and core idea of ​​the present invention. At the same time, for those skilled in the art, according to the idea of ​​the present invention, there will be changes in the specific implementation methods and application scope. In summary, the content of this specification should not be understood as limiting the present invention.

Claims

1. A prestressed concrete cross-web support for an electrified railway contact network, characterized in that: It comprises ultra-high performance concrete and a plurality of arch frames, wherein the plurality of arch frames are cast in the ultra-high performance concrete from bottom to top, wherein the arch frames comprise two groups of arch structures, wherein the arch structures comprise an annular frame and two V-shaped frames, wherein the two V-shaped frames are respectively fixed at two ends of the annular frame, and the two V-shaped frames are symmetrical about the center of the annular frame, wherein the two groups of arch structures are arranged in parallel and fixedly connected by a plurality of vertical short ribs, and the central axes of the annular frames of the two groups of arch structures are both located on the same vertical line.

2. The prestressed concrete cross-web type support for the electrified railway contact network according to claim 1, characterized in that: The annular frame is made of steel bars and is composed of a straight line portion, an arc portion, a second straight line portion and a second arc portion which are fixedly connected end to end in sequence. The straight line portion is parallel to the straight line portion, and the arc portion has the same diameter as the arc portion.

3. The prestressed concrete cross-web type support for the electrified railway contact network according to claim 2, characterized in that: The V-shaped frames are all made of steel bars, and the bottom of the V-shaped frames has a horizontal section, and two ends of the horizontal section are respectively fixedly connected to the first straight line section and the second straight line section.

4. The prestressed concrete cross-web type support for the electrified railway contact network according to claim 3, characterized in that: The horizontal section is welded and fixed to the first straight line portion and the second straight line portion.

5. The prestressed concrete cross-web type support for the electrified railway contact network according to claim 1, characterized in that: Both wings of the V-shaped frame are provided with bending sections, and the bending sections are vertically fixed with the vertical short ribs. The bending sections of the V-shaped frames corresponding to the two groups of the arch structures are welded with the same vertical short rib.

6. The prestressed concrete cross-web type support for the electrified railway contact network according to claim 1, characterized in that: The strength grade of the ultra-high performance concrete is UHPC120.

7. The prestressed concrete cross-web type support for the electrified railway contact network according to claim 1, characterized in that: The ultra-high performance concrete is mainly composed of cement, silica fume, quartz sand, crushed stone, water, steel fiber and water reducing agent, wherein the mass mix ratio of cement, silica fume, quartz sand, crushed stone, water, steel fiber and water reducing agent is 1:0.07:1.31:2.69:0.32:0.17:0.

01.

8. The prestressed concrete cross-web type support for the electrified railway contact network according to claim 7, characterized in that: An admixture is added to the ultra-high performance concrete, and the mass mix ratio of the admixture is 0.34.

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