Sling bridge of ultra-high performance concrete bridge deck slab and reverse tensioning construction method

Abstract

The invention discloses a sling bridge of an ultra-high performance concrete bridge deck and a counter-force tension construction method. The sling bridge comprises a sling serving as a bearing structure and a bridge deck arranged on the sling. The two ends of the sling are anchored in the bridge abutment; a pre-embedded anchoring structure is arranged on one side, facing the sling, of the upper end of each bridge abutment; each pre-embedded anchoring structure is connected with the sling in front of a bridge abutment facing the sling at the corresponding bridge abutment end; the bridge floor comprises a plurality of ultra-high performance concrete prefabricated slabs; and each ultra-high performance concrete precast slab is connected with the sling through a plurality of bridge deck slab anchor bolts. The strength, rigidity and durability of the bridge structure are remarkably improved, construction is easy and convenient, the material strength utilization rate is high, and the deformation rigidity, integrity and durability of the structure are better improved.

Description

Technical Field

[0001] The invention relates to the technical field of bridge construction, and in particular to a suspension bridge of an ultra-high performance concrete bridge deck and a counter-tensioning construction method. Background Art

[0002] A suspension bridge is a type of bridge that uses the main cable or suspension as the main load-bearing structure. The load-bearing structure is anchored at both ends and is located below the bridge deck. The suspension and the bridge deck form a stable whole through columns or connectors. This structure converts the weight of the bridge and the weight of the people on the bridge into the tension of the suspension, and provides the bridge with load-bearing capacity by bearing the tension. The suspension bridge has a light shape and a strong spanning capacity, and is highly applicable in crossing mountain canyons and pedestrian bridges.

[0003] The most common suspension bridge currently uses steel plates and other tension plates as the load-bearing structure, and then lays bridge steel plates, wooden boards or reinforced concrete slabs on the top surface as the bridge deck. This type of structure has low vertical and horizontal stiffness, which leads to large live load displacement, making the traffic less comfortable, and even resonance when vehicles or pedestrians pass, causing structural failure. This is the biggest limitation to the span breakthrough and promotion of suspension bridges.

[0004] Moreover, insufficient durability is another defect of suspension bridges. After long-term use, the integrity of the structure is reduced, resulting in further increase in live load displacement, which is very prone to wear, resulting in damage or even breakage of the beam. In order to increase the rigidity of the structure, methods such as tensioning prestress, setting transverse or spatial cables, and increasing the weight of the bridge deck are usually used. The above methods are all based on the perspective of increasing the cross-section and materials, but not from the perspective of optimizing the construction steps of the suspension bridge, adjusting the internal force state when the bridge is completed, and making full use of the performance of the structural materials.

[0005] The use of thick suspension straps, the installation of transverse or spatial cables, and the increase in the weight of the bridge deck will lead to high material consumption, difficulty in manufacturing and construction, reduced structural economy, and a large workload for subsequent maintenance.

[0006] Regarding the method of increasing the integrity and rigidity of the suspension bridge structure by tensioning stress in the bridge deck, since the prestressing force needs to be anchored integrally on the abutment or main beam, it is difficult to re-apply the prestressing force after the cast-in-place bridge deck or prefabricated bridge deck is damaged and rebuilt, and the long-term maintenance of the structure is not utilized.

[0007] Ultra-high performance concrete (UHPC) is a cement-based material with high elastic modulus, ultra-high strength, ultra-high toughness and ultra-high durability.

[0008] Therefore, how to apply ultra-high performance concrete to suspension bridges to improve the structural strength, overall stiffness and durability of bridges has become a technical problem that technical personnel in this field urgently need to solve. Summary of the invention

[0009] In view of the above-mentioned defects of the prior art, the present invention provides a suspension bridge and a counter-tensioning construction method for an ultra-high performance concrete bridge deck, the purpose of which is to improve the overall stiffness and durability of the bridge's spanning capacity.

[0010] To achieve the above-mentioned object, the present invention discloses a suspension bridge of an ultra-high performance concrete bridge deck, comprising a suspension as a load-bearing structure, and a bridge deck arranged on the suspension;

[0011] Both ends of the suspension strap are anchored in the abutment;

[0012] A pre-buried anchoring structure is provided on the upper end of each abutment facing the suspension belt;

[0013] Each of the embedded anchoring structures is connected to the suspension belt at the corresponding abutment end facing the abutment front of the suspension belt;

[0014] The bridge deck includes a number of ultra-high performance concrete precast panels;

[0015] Each of the ultra-high performance concrete precast panels is connected to the suspension belt via a plurality of bridge deck anchor bolts.

[0016] Preferably, the suspension belt is in the shape of a plate, a box or a cable, and is made of steel, concrete and / or fiber-reinforced material;

[0017] If the suspension belt is box-shaped, the suspension belt is connected to the bridge deck by anchor bolts;

[0018] If the suspension belt is in the shape of a cable, a buckle is used to connect the suspension belt to the bridge deck.

[0019] Preferably, the front of the abutment of each abutment is cast in an arc shape to achieve a smooth transition of deformation of the suspension belt from the corresponding abutment to the middle of the span of the suspension belt.

[0020] Preferably, each end of the embedded anchoring structure embedded in the corresponding abutment is provided with a suspender embedded end anchor plate, and a portion close to the end is provided with a plurality of suspender embedded shear connectors along the length.

[0021] Preferably, each of the sling pre-embedded shear-resistant connectors comprises a shear nail, an anchor bolt, or a PBL connector.

[0022] Preferably, a buffer pad is provided between each of the ultra-high performance concrete precast panels and the suspension belt; a precast panel buffer pad is provided between every two adjacent ultra-high performance concrete precast panels; and a beam end elastic expansion joint is provided at the position where the bridge deck connects with each of the abutments.

[0023] The present invention also provides a method for the reverse tensioning construction of a suspension bridge with an ultra-high performance concrete bridge deck, which is characterized by comprising the following steps:

[0024] Step A1, constructing all the abutments and the corresponding embedded anchoring structures, and arranging a portion of the suspension belts near the abutments to extend toward the suspension belts located in the middle of the span;

[0025] Step A2, connecting the suspension belt located in the middle of the span with the portion of the suspension belt extending from the corresponding abutment at the front position of the abutment of each abutment to form the initially connected suspension belt;

[0026] Step A3, suspending a number of counterweights on the suspension belt located in the middle of the span according to the design line shape requirements, so that the suspension belt generates initial tension and reaches a preliminary ideal line shape;

[0027] Step A4, connecting each of the ultra-high performance concrete precast panels to the suspension belt through a plurality of the bridge deck anchor bolts, and providing a buffer pad, a precast panel buffer pad and an elastic expansion joint at the beam end, so that the tension of the suspension belt is further increased under the action of gravity, thereby forming a vertical stiffness that meets the requirements;

[0028] Step A5: according to the design line requirements, all the counterweights are removed in sequence, the suspension belt rebounds and the initial tension is reduced, and at the same time, the bridge deck composed of the ultra-high performance concrete precast panels is compacted.

[0029] Preferably, after completing step 5, the bridge deck auxiliary device is installed to further increase the intermediate tension of the suspension belt, but the bridge deck is still under pressure as a whole; the bridge deck auxiliary device includes a bridge deck railing.

[0030] Preferably, when any of the ultra-high performance concrete precast panels is damaged, the following construction steps are used for repair and replacement:

[0031] Step B1, removing the damaged ultra-high performance concrete precast panel and the corresponding bridge deck anchor bolts, suspending the counterweight on the ultra-high performance concrete precast panel to be replaced and the adjacent ultra-high performance concrete precast panel, forming the initial construction tension in the suspension belt of the maintenance section and controlling the linear shape;

[0032] Step B2, removing the ultra-high performance concrete precast panel from the suspension belt and replacing it with a new ultra-high performance concrete precast panel, and installing the corresponding buffer pad and the precast panel buffer pad;

[0033] Step B3: according to the design linear requirements, all the counterweights are removed in sequence, the suspension belt rebounds, the newly replaced ultra-high performance concrete precast panels are compacted to form pre-compression stress, and the corresponding positions of the suspension belt restore stable initial tension.

[0034] Preferably, the reaction force is applied to the suspension belt by bridge deck loading, reaction frame loading or magnetic loading.

[0035] Beneficial effects of the present invention:

[0036] The present invention significantly improves the strength, rigidity and durability of the bridge structure, is simple and convenient to construct, has a high utilization rate of material strength, and is also more conducive to improving the deformation rigidity, integrity and durability of the structure.

[0037] The concept, specific structure and technical effects of the present invention will be further described below in conjunction with the accompanying drawings to fully understand the purpose, characteristics and effects of the present invention. BRIEF DESCRIPTION OF THE DRAWINGS

[0038] Figure 1 A schematic structural diagram of an embodiment of the present invention is shown.

[0039] Figure 2 A schematic structural diagram of a pre-buried anchoring structure in one embodiment of the present invention is shown.

[0040] Figure 3 A schematic diagram of a partially enlarged cross-sectional structure of a plate-shaped suspension belt in one embodiment of the present invention is shown.

[0041] Figure 4 A partially enlarged cross-sectional structural schematic diagram showing a box-shaped suspension belt in one embodiment of the present invention.

[0042] Figure 5 A schematic diagram of a partially enlarged cross-sectional structure of a cable-shaped suspension belt in an embodiment of the present invention is shown.

[0043] Figure 6 A schematic diagram of step A1 in an embodiment of the present invention is shown.

[0044] Figure 7 A schematic diagram of A2 in one embodiment of the present invention is shown.

[0045] Figure 8 A schematic diagram of A3 in one embodiment of the present invention is shown.

[0046] Fig. 9 A schematic diagram of A4 in one embodiment of the present invention is shown.

[0047] Fig.10 A schematic diagram of A5 in one embodiment of the present invention is shown.

[0048] Fig.11 A schematic diagram showing the installation of bridge deck accessories in one embodiment of the present invention.

[0049] Fig.12 A schematic diagram of B1 in an embodiment of the present invention is shown.

[0050] Fig.13 A schematic diagram of B2 in an embodiment of the present invention is shown.

[0051] Fig.14 A schematic diagram of B3 in an embodiment of the present invention is shown. DETAILED DESCRIPTION

[0052] Example

[0053] like Figure 1 and Figure 2 As shown, the suspension bridge of the ultra-high performance concrete bridge deck includes a suspension belt 2 as a load-bearing structure, and a bridge deck arranged on the suspension belt 2;

[0054] Both ends of the suspension strap 2 are anchored in the abutment 1;

[0055] A pre-buried anchoring structure 5 is provided on the upper end of each abutment 1 facing the suspension belt 2;

[0056] Each pre-buried anchoring structure 5 is connected to the suspension belt 2 at the end of the corresponding abutment 1 facing the abutment front of the suspension belt 2;

[0057] The bridge deck includes several ultra-high performance concrete precast panels 3;

[0058] Each ultra-high performance concrete precast panel 3 is connected to the suspension belt 2 via a plurality of bridge deck anchor bolts 9 .

[0059] The present invention utilizes ultra-high performance concrete prefabricated panels 3 to form the bridge deck, which significantly improves the strength, rigidity and durability of the bridge structure with the suspension belt 2, and the construction is simple and convenient.

[0060] The linear shape and stress state of the suspension belt 2 are adjustable, in addition to selecting different stress-free lengths of the plate belt. The ultra-high performance concrete precast slab 3 as the bridge deck is connected to the suspension belt 2 by the bridge deck anchor bolt 9, which is convenient for repairing the bridge deck after damage. After damage, the bridge deck can also be partially replaced by the reverse pulling method to restore the linear shape and overall stress state of the whole bridge.

[0061] like Figures 3 to 5 As shown, in some embodiments, the suspension belt 2 is in the shape of a plate, a box or a cable, and the material is steel, concrete and / or fiber-reinforced material;

[0062] If the suspension belt 2 is box-shaped, the suspension belt 2 is connected to the bridge deck using anchor bolts 9;

[0063] If the suspension belt 2 is in the shape of a cable, the suspension belt 2 is connected to the bridge deck using the buckle 13 .

[0064] In practical applications, the suspension belt 2 is manufactured using steel, concrete, fiber-reinforced materials, or a combination thereof.

[0065] In some embodiments, the front of each abutment 1 is cast in an arc shape to achieve a smooth transition of deformation of the suspension belt 2 from the corresponding abutment 1 to the mid-span of the suspension belt 2 .

[0066] In some embodiments, each end of the embedded anchor structure 5 embedded in the corresponding abutment 1 is provided with a suspender embedded end anchor plate 6, and a portion close to the end is provided with a plurality of suspender embedded shear connectors 14 along the length.

[0067] In some embodiments, each suspender pre-embedded shear connector 14 includes a shear nail, an anchor bolt, or a PBL connector.

[0068] In some embodiments, a buffer pad 10 is provided between each ultra-high performance concrete precast panel 3 and the suspension belt 2; a precast panel buffer pad 15 is provided between every two adjacent ultra-high performance concrete precast panels 3; and a beam end elastic expansion joint 8 is provided at the position where the bridge deck connects to each abutment 1.

[0069] The provision of the above-mentioned buffer pad 10, prefabricated plate buffer pad 15 and beam end elastic expansion joint 8 can reduce the impact wear during the use of the bridge and make the bridge more adaptable to temperature deformation.

[0070] like Figures 6 to 10 As shown, the present invention also provides a reverse tensioning construction method for a suspension bridge of an ultra-high performance concrete bridge deck, comprising the following steps:

[0071] Step A1, construct all abutments 1 and corresponding embedded anchor structures 5, and set a portion of the suspension belt 2 close to the abutment 1 to extend toward the suspension belt 2 located in the middle of the span;

[0072] Step A2, connecting the suspension belt 2 located in the middle of the span with the part of the suspension belt 2 extending from the corresponding abutment 1 at the front position of the abutment of each abutment 1 to form a primary connected suspension belt 2;

[0073] Step A3, suspending a number of counterweights 7 on the suspension belt 2 located in the middle of the span according to the design line shape requirements, so that the suspension belt 2 generates initial tension and reaches a preliminary ideal line shape;

[0074] Step A4, each ultra-high performance concrete precast panel 3 is connected to the suspension belt 2 through a plurality of bridge deck anchor bolts 9, and a buffer pad 10, a precast panel buffer pad 15 and a beam end elastic expansion joint 8 are provided, so that the tension of the suspension belt 2 is further increased under the action of gravity, so as to form a vertical stiffness that meets the requirements;

[0075] Step A5: according to the design line requirements, all the counterweights 7 are removed in sequence, the suspension belt 2 rebounds and the initial tension is reduced, and at the same time, the bridge deck composed of the ultra-high performance concrete precast panels 3 is compacted.

[0076] During construction, the linearity and stress state of the bridge can be adjusted by adjusting the weight of the counter-tension and the order of removing the counterweight. In addition to improving the geometric stiffness of the suspension belt, the counter-tension method also provides pre-compression stress for the ultra-high performance concrete precast slab 3 as the bridge deck. The material strength utilization rate is high, and it is also more conducive to improving the deformation stiffness, integrity and durability of the structure.

[0077] Through the above steps, a stable pre-compression stress is formed in the ultra-high performance concrete precast panel 3, a stable initial tension is formed in the suspension belt 2, and the entire structure forms a stable system with relatively large rigidity.

[0078] like Fig.11 As shown, after completing step 5, the bridge deck auxiliary equipment is installed to further increase the middle tension of the suspension belt 2, but the bridge deck is still under pressure as a whole; the bridge deck auxiliary equipment includes the bridge deck railing 4.

[0079] like Figure 12 to Figure 14 As shown, in some embodiments, when any ultra-high performance concrete precast panel 3 is damaged, the following construction steps are used for repair and replacement:

[0080] Step B1, remove the damaged ultra-high performance concrete precast panel 3 and the corresponding bridge deck anchor bolts 9, suspend the counterweight 7 on the ultra-high performance concrete precast panel 3 to be replaced and the adjacent ultra-high performance concrete precast panel 3, form the initial construction tension in the suspension belt 2 of the maintenance section and control the line shape;

[0081] Step B2, removing the ultra-high performance concrete precast panel 3 from the suspension belt 2 and replacing it with a new ultra-high performance concrete precast panel 3, and installing corresponding buffer pads 10 and precast panel buffer pads 15;

[0082] Step B3: according to the design line requirements, all the counterweights 7 are removed in turn, the suspension belt 2 rebounds, the newly replaced ultra-high performance concrete precast panels 3 are compacted to form pre-compression stress, and the corresponding positions of the suspension belt 2 restore stable initial tension.

[0083] Through the above technical means, the stable initial tension is restored in the suspension belt in the maintenance section, and the entire structure is restored to a stable system with greater rigidity. After completion, the bridge deck system is restored, and the maintenance is completed. Through the above technical means, the structure can be restored to an ideal linear shape and stress state.

[0084] In some embodiments, a bridge deck loading, a reaction frame loading or a magnetic loading method is used to apply a reaction force to the suspension belt 2 .

[0085] The preferred specific embodiments of the present invention are described in detail above. It should be understood that a person skilled in the art can make many modifications and changes based on the concept of the present invention without creative work. Therefore, any technical solution that can be obtained by a person skilled in the art through logical analysis, reasoning or limited experiments based on the concept of the present invention on the basis of the prior art should be within the scope of protection determined by the claims.

Claims

1. A suspension bridge with an ultra-high performance concrete deck; characterized in that: It comprises a suspension belt (2) as a load-bearing structure, and a bridge deck arranged on the suspension belt (2); Both ends of the suspension belt (2) are anchored in the abutment (1); A pre-buried anchoring structure (5) is provided on one side of the upper end of each abutment (1) facing the suspension belt (2); Each of the embedded anchor structures (5) is connected to the suspension belt (2) at the end of the corresponding abutment (1) toward the abutment front of the suspension belt (2); The bridge deck comprises a plurality of ultra-high performance concrete prefabricated panels (3); Each of the ultra-high performance concrete prefabricated panels (3) is connected to the suspension belt (2) via a plurality of bridge deck anchor bolts (9).

2. The suspension bridge with ultra-high performance concrete bridge deck according to claim 1, characterized in that: The suspension belt (2) is in the shape of a plate, a box or a cable, and is made of steel, concrete and / or fiber-reinforced material; If the suspension belt (2) is box-shaped, the suspension belt (2) is connected to the bridge deck using anchor bolts (9); If the suspension belt (2) is in the shape of a cable, a buckle (13) is used to connect the suspension belt (2) to the bridge deck.

3. The suspension bridge with ultra-high performance concrete bridge deck according to claim 1, characterized in that: The front of the abutment of each abutment (1) is cast in an arc shape, so as to realize a smooth transition of deformation of the suspension belt (2) from the corresponding abutment (1) to the mid-span of the suspension belt (2).

4. The suspension bridge with ultra-high performance concrete bridge deck according to claim 1, characterized in that: The end of each embedded anchor structure (5) embedded in the corresponding abutment (1) is provided with a suspender embedded end anchor plate (6), and the portion close to the end is provided with a plurality of suspender embedded shear connectors (14) along the length.

5. The suspension bridge with ultra-high performance concrete bridge deck according to claim 1, characterized in that: Each of the suspender pre-embedded anti-shear connectors (14) comprises a shear nail, an anchor bolt, and a PBL connector.

6. The suspension bridge with ultra-high performance concrete bridge deck according to claim 1, characterized in that: A buffer pad (10) is provided between each of the ultra-high performance concrete precast panels (3) and the suspension belt (2); a precast panel buffer pad (15) is provided between each two adjacent ultra-high performance concrete precast panels (3); and a beam end elastic expansion joint (8) is provided at a position where the bridge deck is connected to each of the abutments (1).

7. The anti-tensioning construction method of a suspension bridge with an ultra-high performance concrete bridge deck according to claim 1, characterized in that: The steps include: Step A1, constructing all the abutments (1) and the corresponding embedded anchoring structures (5), and arranging a portion of the suspension belt (2) close to the abutments (1) to extend toward the suspension belt (2) located in the middle of the span; Step A2, connecting the suspension belt (2) located in the middle of the span with the portion of the suspension belt (2) extending from the corresponding abutment (1) at the front position of the abutment of each abutment (1) to form the initially connected suspension belt (2); Step A3, suspending a number of counterweights (7) on the suspension belt (2) located in the middle of the span according to the design line shape requirements, so that the suspension belt (2) generates initial tension and reaches a preliminary ideal line shape; Step A4, connecting each of the ultra-high performance concrete precast panels (3) to the suspension belt (2) through a plurality of the bridge deck anchor bolts (9), and providing a buffer pad (10), a precast panel buffer pad (15) and a beam end elastic expansion joint (8), so that the tension of the suspension belt (2) is further increased under the action of gravity, thereby forming a vertical stiffness that meets the requirements; Step A5: according to the design line requirements, all the counterweights (7) are removed in sequence, the suspension belt (2) rebounds and the initial tension is reduced, and at the same time, the bridge deck composed of the ultra-high performance concrete precast panels (3) is compacted.

8. The anti-tensioning construction method of a suspension bridge with an ultra-high performance concrete bridge deck according to claim 7, characterized in that: After completing step 5, the bridge deck auxiliary equipment is installed to further increase the intermediate tension of the suspension belt (2), but the bridge deck is still under pressure as a whole; the bridge deck auxiliary equipment includes a bridge deck railing (4).

9. The anti-tensioning construction method of a suspension bridge with an ultra-high performance concrete bridge deck according to claim 7, characterized in that: When any of the ultra-high performance concrete precast panels (3) is damaged, the following construction steps are used to repair and replace it: Step B1, removing the damaged ultra-high performance concrete precast panel (3) and the corresponding bridge deck anchor bolts (9), suspending the counterweight (7) on the ultra-high performance concrete precast panel (3) to be replaced and the adjacent ultra-high performance concrete precast panel (3), forming an initial construction tension in the suspension belt (2) of the maintenance section and controlling the linear shape; Step B2, removing the ultra-high performance concrete precast panel (3) from the suspension belt (2) and replacing it with a new ultra-high performance concrete precast panel (3), and installing the corresponding buffer pad (10) and the precast panel buffer pad (15); Step B3: according to the design linear requirements, all the counterweights (7) are removed in sequence, the suspension belt (2) rebounds, the newly replaced ultra-high performance concrete precast panels (3) are compacted to form pre-compression stress, and the corresponding positions of the suspension belt (2) restore stable initial tension.

10. The anti-tensioning construction method of a suspension bridge with an ultra-high performance concrete bridge deck according to claim 7, characterized in that: Alternatively, a bridge deck loading, a reaction frame loading or a magnetic loading method is used to apply a reaction force to the suspension belt (2).

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