Stone arch bridge reinforcing structure

Abstract

The stone arch bridge reinforcing structure is composed of an arch foot, an arch ring and a side wall, and is characterized in that the stone arch bridge reinforcing structure is composed of a lower anti-seepage geomembrane, an arch back filler, an upper anti-seepage geomembrane, a low-grade concrete base layer, an isolation layer and an assembly type prestressed concrete surface layer, the lower anti-seepage geomembrane is laid on the arch back and the arch foot, and the lower anti-seepage geomembrane is laid on the arch ring. The arch back filler is foam light soil; the upper anti-seepage geomembrane is laid on the arch back filler, the low-grade concrete base layer is poured on the upper anti-seepage geomembrane, the isolation layer is arranged on the low-grade concrete base layer, and the fabricated prestressed concrete surface layer is formed by laying pre-tensioning plates for roads. According to the reinforcing structure of the stone arch bridge, the foam light soil is used for replacing the original back filler, the dead load of the arch bridge is greatly reduced, the assembled prestressed concrete surface layer is used for replacing a common reinforced concrete surface layer, the overall rigidity of the road surface is increased, the stress of the arch ring is more uniform, and therefore the bearing capacity of the stone arch bridge is improved.

Description

Technical Field

[0001] The utility model relates to a reinforcement structure for a stone arch bridge, and more specifically, to a reinforcement structure for a stone arch bridge. Background Technique

[0002] The stone arch bridge is the crystallization of the wisdom of the ancestors, with advantages such as beautiful shape and strong load-bearing capacity. With the rapid development of the economy, there are more and more heavy-load traffics, and many stone arch bridges can no longer meet the requirements of carrying heavy-load traffics. People usually reinforce the arch ring. At present, the commonly used method for reinforcing a stone arch bridge is to build an auxiliary arch ring made of reinforced concrete under the arch ring. Since the original arch ring of the stone arch bridge is made of stone, but the combination of stone and concrete often has poor effect, and the improvement of the load-bearing capacity is limited. For this reason, the utility model proposes a new type of reinforcement structure for a stone arch bridge without constructing a reinforced concrete arch ring. Summary of the Invention

[0003] The utility model provides a reinforcement structure for a stone arch bridge to overcome the above technical problems.

[0004] The reinforcement structure of the stone arch bridge of the utility model, the stone arch bridge is composed of arch feet, an arch ring and side walls. The two ends of the arch ring are fixed on the arch feet, and the side walls are fixed on the arch ring; its characteristics are: the reinforcement structure of the stone arch bridge is composed of a lower anti-seepage geomembrane, arch back filling, an upper anti-seepage geomembrane, a low-strength concrete base layer, an isolation layer and an assembled prestressed concrete surface layer. The lower anti-seepage geomembrane is laid on the arch back and arch feet, the arch back filling is filled above the lower anti-seepage geomembrane, and the arch back filling is lightweight foamed soil; the upper anti-seepage geomembrane is laid on the arch back filling, the low-strength concrete base layer is poured on the upper anti-seepage geomembrane, the isolation layer is arranged on the low-strength concrete base layer, and the assembled prestressed concrete surface layer is laid on the isolation layer. The assembled prestressed concrete surface layer is evenly laid by road-use pretensioned slabs.

[0005] In the reinforcement structure of the stone arch bridge of the utility model, the isolation layer is a double-layer geotextile, and the double-layer geotextiles are bonded by hot asphalt.

[0006] In the reinforcement structure of the stone arch bridge of the utility model, the arch back filling within 80 cm from the low-strength concrete base layer uses lightweight concrete with a density of 560 kg / m 3 ~600 kg / m 3 and a 7-day compressive strength of not less than 0.8 MPa. The arch back filling more than 80 cm outside the low-strength concrete base layer uses lightweight concrete with a density of 520 kg / m 3 ~560 kg / m 3 and a 7-day compressive strength of not less than 0.6 MPa.

[0007] The reinforcement structure of the stone arch bridge of the present utility model, the permeability coefficient K of the lower anti-seepage geomembrane and the upper anti-seepage geomembrane is less than 10 -13 cm / s.

[0008] The reinforcement structure of the stone arch bridge of the present utility model, the 7-day compressive strength of the low-grade concrete base layer after pouring is not less than 15 MPa.

[0009] The reinforcement structure of the stone arch bridge of the present utility model, the adjacent pre-tensioned slabs in the left and right directions in the precast prestressed concrete surface layer are connected by longitudinal self-stress joints, and the adjacent pre-tensioned slabs in the front and back directions are connected by transverse self-stress joints; the longitudinal self-stress joint is composed of high-expansion concrete and longitudinal self-stress joint transverse bars poured therein, the transverse self-stress joint is composed of high-expansion concrete and transverse self-stress joint longitudinal bars poured therein, and both ends of the longitudinal self-stress joint transverse bars and both ends of the transverse self-stress joint longitudinal bars are anchored in the adjacent two pre-tensioned slabs.

[0010] The reinforcement structure of the stone arch bridge of the present utility model, the pre-tensioned slab is composed of ordinary concrete, steel strands and pre-tensioned slab transverse bars poured therein, the length direction of the steel strands is consistent with the length direction of the pre-tensioned slab, and the length direction of the pre-tensioned slab transverse bars is consistent with the width direction of the pre-tensioned slab.

[0011] The beneficial effects of the present utility model are as follows: The reinforcement structure of the stone arch bridge of the present utility model is composed of a lower anti-seepage geomembrane, arch back filling, an upper anti-seepage geomembrane, a low-grade concrete base layer, an isolation layer and a precast prestressed concrete surface layer arranged from bottom to top on the arch back and arch feet. The arch back filling adopts foam light soil, and the upper and lower anti-seepage geomembranes wrap the foam light soil to prevent water from entering the foam light soil. The low-grade concrete base layer is located between the upper anti-seepage geomembrane and the isolation layer, and the precast prestressed concrete surface layer is laid by road-use pre-tensioned slabs; It can be seen that since the original arch back filling is replaced by foam light soil, the density of the foam light soil is small, which greatly reduces the dead load of the arch bridge and also reduces the pressure on the side walls of the stone arch bridge; at the same time, replacing the ordinary reinforced concrete surface layer with a precast prestressed concrete surface layer increases the overall stiffness of the road surface, makes the force of the arch ring more uniform, and thus improves the bearing capacity of the stone arch bridge. Brief Description of the Drawings

[0012] Figure 1 is a structural schematic diagram of the reinforcement structure of the stone arch bridge of the present utility model;

[0013] Figure 2 is Figure 1 a cross-sectional view of the A-A section in

[0014] Figure 3 is a top view of the precast prestressed concrete surface layer in the present utility model;

[0015] Figure 4This is the cross-sectional structure diagram of the precast prestressed concrete surface layer in the present utility model;

[0016] Figure 5 This is the longitudinal-sectional structure diagram of the precast prestressed concrete surface layer in the present utility model.

[0017] In the figure: 1 lower anti-seepage geomembrane, 2 backfill of arch, 3 upper anti-seepage geomembrane, 4 low-strength concrete base, 5 isolation layer, 6 precast prestressed concrete surface layer, 7 arch springing, 8 arch ring, 9 back of arch, 10 side wall, 11 pretensioned slab, 12 longitudinal self-stressing joint, 13 transverse self-stressing joint, 14 steel strand, 15 transverse reinforcement of pretensioned slab, 16 ordinary concrete, 17 high-expansion concrete, 18 transverse reinforcement of longitudinal self-stressing joint, 19 longitudinal reinforcement of transverse self-stressing joint. Specific implementation manners

[0018] The present utility model will be further described below in conjunction with the accompanying drawings and embodiments.

[0019] As Figure 1 shown, the structural schematic diagram of the stone arch bridge reinforcement structure of the present utility model is given. Figure 2 The Figure 1 cross-sectional view of the A-A section in is given. The shown stone arch bridge is composed of an arch springing 7, an arch ring 8 and a side wall 10. The upper surface of the arch ring 8 is the back of arch 9. The two ends of the arch ring 8 are fixed on the arch springing 7, and the side wall 10 is fixed above the two ends of the arch ring 8. The shown stone arch bridge reinforcement structure is composed of a lower anti-seepage geomembrane 1, a backfill of arch 2, an upper anti-seepage geomembrane 3, a low-strength concrete base 4, an isolation layer 5 and a precast prestressed concrete surface layer 6 which are sequentially arranged from bottom to top on the back of arch 9 and the arch springing 7.

[0020] The shown lower anti-seepage geomembrane 1 is laid on the upper surfaces of the back of arch 9 and the arch springing 7. The backfill of arch 2 uses foamed lightweight soil. The foamed lightweight soil is filled above the lower anti-seepage geomembrane 1. The upper anti-seepage geomembrane 3 is laid above the backfill of arch 2 composed of the foamed lightweight soil. In this way, the filled foamed lightweight soil is hermetically wrapped by the lower anti-seepage geomembrane 1, the upper anti-seepage geomembrane 3 and the two side walls 10, which can effectively avoid the entry of moisture, is beneficial to maintaining the dryness of the foamed lightweight soil, ensures the bearing capacity of the foamed lightweight soil, and also ensures that the foamed lightweight soil does not increase in weight due to water absorption.

[0021] The upper anti-seepage geomembrane 3 shown is laid with a low-strength concrete base 4 above it, and an isolation layer 5 is laid above the low-strength concrete base 4. The isolation layer 5 uses a double-layer geotextile, and the double-layer geotextiles are bonded by hot asphalt. In this way, the low-strength concrete base 4 is equivalent to being wrapped between the upper anti-seepage geomembrane 3 and the isolation layer 5, avoiding the entry of moisture into the low-strength concrete base 4, which is beneficial to ensuring the stability of the low-strength concrete base 4. As shown, the precast prestressed concrete surface layer 6 is composed of uniformly laid road-use pretensioned slabs 11.

[0022] It can be seen that the backfill 2 of the arch uses low-density foam concrete to replace the existing backfill of relatively high density such as crushed stone or soil, greatly reducing the dead load of the arch bridge. At the same time, it also reduces the pressure on the side wall, which is beneficial to improving the bearing capacity of the stone arch bridge. At the same time, the assembled prestressed concrete surface layer is used to replace the ordinary reinforced concrete surface layer, increasing the overall stiffness of the road surface, making the force on the arch ring more uniform, and further improving the bearing capacity of the stone arch bridge.

[0023] Such as Figure 3 , Figure 4 and Figure 5 As shown, the top view, cross-sectional structure diagram and longitudinal section structure diagram of the assembled prestressed concrete surface layer in the present invention are respectively given. In the shown assembled prestressed concrete surface layer, the adjacent pretensioned slabs 11 on the left and right are connected by longitudinal self-stress seams 12, and the adjacent pretensioned slabs 11 in the front and back are connected by transverse self-stress seams 13. The length direction of the longitudinal self-stress seam 12 is consistent with the road driving direction, and the length direction of the transverse self-stress seam 13 is consistent with the road width direction.

[0024] The shown longitudinal self-stress seam 12 is composed of high-expansion concrete 17 and longitudinal self-stress seam transverse bars 18 cast in the high-expansion concrete 17. The transverse self-stress seam 13 is composed of high-expansion concrete 17 and transverse self-stress seam longitudinal bars 19 cast in it. Both the longitudinal self-stress seam transverse bars 18 and the transverse self-stress seam longitudinal bars 19 are composed of two anchor bars with their ends anchored in the adjacent two pretensioned slabs 11. After the pretensioned slabs 11 are laid in place, the longitudinal self-stress seam transverse bars 18 or the transverse self-stress seam longitudinal bars 19 are formed by welding the two aligned anchor bars.

[0025] After the high-expansion concrete in the longitudinal self-stress seam 12 and the transverse self-stress seam 13 is poured, it will generate compressive stress on the end faces of the adjacent pretensioned slabs 11 on both sides, improving the bearing capacity of the ends of the pretensioned slabs 11. The pretensioned slabs 11 connected by the longitudinal self-stress seam 12 and the transverse self-stress seam 13 can form an assembled prestressed concrete surface layer 6 with a relatively large overall stiffness, which can make the force on the underlying arch ring more uniform and is beneficial to improving the bearing capacity of the stone arch bridge.

[0026] The shown pretensioned slab 11 is composed of ordinary concrete 16, steel strands 14 and pretensioned slab transverse bars 15 cast in the ordinary concrete 16. The length direction of the steel strands 14 is consistent with the length direction of the pretensioned slab 11, and the steel strands 14 are uniformly arranged in the width direction of the pretensioned slab 11. The length direction of the pretensioned slab transverse bars 15 is consistent with the width direction of the pretensioned slab 11 and is uniformly arranged in the length direction of the pretensioned slab 11.

[0027] In order to minimize the weight of the backfill 2 of the arch while ensuring that its bearing capacity meets the requirements, the backfill 2 within 480 cm from the low-strength concrete base is made of lightweight concrete with a density of 560 kg / m 3 ~600 kg / m 3 and a 7-day compressive strength of not less than 0.8 MPa. The backfill 2 within 80 cm outside the low-strength concrete base is made of lightweight concrete with a density of 520 kg / m 3 ~560 kg / m 3 and a 7-day compressive strength of not less than 0.6 MPa.

[0028] Among them, in order to ensure that the anti-seepage of the lower anti-seepage geomembrane 1 and the upper anti-seepage geomembrane 3 meets the requirements, it is required that the permeability coefficient K of the anti-seepage geomembrane 1 and the upper anti-seepage geomembrane 3 is less than 10 -13 cm / s. In order to ensure that the bearing capacity of the low-strength concrete base meets the requirements, the 7-day compressive strength of the low-strength concrete base 4 after pouring is not less than 15 MPa. After the high-expansion concrete 17 in the longitudinal self-stress joint 12 and the transverse self-stress joint 13 is poured, it needs to be water-cured for 7 days.

Claims

1. A stone arch bridge reinforcement structure, the stone arch bridge consists of an arch foot (7), an arch ring (8) and a side wall (10), the two ends of the arch ring are fixed to the arch foot, and the side wall is fixed to the arch ring; characterized in that: The stone arch bridge reinforcement structure is composed of a lower anti-seepage geomembrane (1), an arch back filler (2), an upper anti-seepage geomembrane (3), a low-grade concrete base layer (4), an isolation layer (5) and an assembled prestressed concrete surface layer (6), wherein the lower anti-seepage geomembrane is laid on the arch back and the arch foot, the arch back filler is filled on the top of the lower anti-seepage geomembrane, and the arch back filler is foamed lightweight soil; the upper anti-seepage geomembrane is laid on the arch back filler, the low-grade concrete base layer is cast on the upper anti-seepage geomembrane, the isolation layer is arranged on the low-grade concrete base layer, the assembled prestressed concrete surface layer is laid on the isolation layer, and the assembled prestressed concrete surface layer is formed by evenly laying road prestressed plates (11).

2. The stone arch bridge reinforcement structure according to claim 1, characterized in that: The isolation layer (5) is a double-layer geotextile, and the double-layer geotextile is bonded by hot asphalt.

3. The stone arch bridge reinforcement structure according to claim 1 or 2, characterized in that: The backfill material (2) within 80 cm from the low-grade concrete base (4) is made of a density of 560 kg / m 3 ~600kg / m 3 , lightweight concrete with a 7-day compressive strength of not less than 0.8MPa, and a density of 520kg / m3 for the arch backfill 80cm away from the low-grade concrete base 3 ~560kg / m 3 , lightweight concrete with 7-day compressive strength not less than 0.6MPa.

4. The stone arch bridge reinforcement structure according to claim 1 or 2, characterized in that: The permeability coefficient K of the lower anti-seepage geomembrane (1) and the upper anti-seepage geomembrane (3) is less than 10 -13 cm / s.

5. The stone arch bridge reinforcement structure according to claim 1 or 2, characterized in that: The compressive strength of the low-grade concrete base (4) is not less than 15 MPa 7 days after pouring.

6. The stone arch bridge reinforcement structure according to claim 1 or 2, characterized in that: The prestressed plates (11) adjacent to each other on the left and right sides of the assembled prestressed concrete surface layer (6) are connected via longitudinal self-stressed seams (12), and the prestressed plates adjacent to each other on the front and back sides are connected via transverse self-stressed seams (13); the longitudinal self-stressed seams are formed by high-expansion concrete (17) and longitudinal self-stressed seam transverse ribs (18) cast therein, and the transverse self-stressed seams are formed by high-expansion concrete and transverse self-stressed seam longitudinal ribs (19) cast therein, and both ends of the longitudinal self-stressed seam transverse ribs and both ends of the transverse self-stressed seam longitudinal ribs are anchored in two adjacent prestressed plates.

7. The stone arch bridge reinforcement structure according to claim 1 or 2, characterized in that: The pre-stressed plate (11) is composed of ordinary concrete (16) and steel strands (14) and pre-stressed plate transverse reinforcements (15) cast therein, the length direction of the steel strands is consistent with the length direction of the pre-stressed plate, and the length direction of the pre-stressed plate transverse reinforcements is consistent with the width direction of the pre-stressed plate.

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