Prestress device for preventing differential settlement of road and construction method thereof

Abstract

The application discloses a prestress device for preventing differential settlement of roads and a construction method, and relates to the technical field of road construction, which can prevent the upper soil from settling down. The prestress device comprises a hollow screw pipe, a prestress module, a bearing module and a stabilizing module, wherein the hollow screw pipe is arranged in a shell, the prestress module and the bearing module are arranged on the outer jacket of the hollow screw pipe, and the bottom of the hollow screw pipe is connected with the stabilizing module. A grouting pipe is arranged on the bearing module, the grouting pipe is communicated with the hollow screw pipe, and the bearing plate is formed by grouting. The prestress component is arranged on the prestress module, the both ends of the prestress component are provided with clamping springs, and the prestress of the prestress component is released by the clamping springs on the upper end. The prestress device for preventing differential settlement of roads can replace the gradually disappearing pore water pressure and transmit force to the upper bearing module to support the upper soil, so that the upper soil is prevented from settling down.

Description

Technical Field

[0001] This invention relates to the field of road settlement prevention devices, specifically to a prestressed device and construction method for preventing differential road settlement. Background Technology

[0002] During operation, roads often experience settlement as the foundation and subgrade consolidate, especially in softer sections. Due to the heterogeneity of subgrade materials and foundation, uneven settlement frequently occurs, resulting in differential settlement. Differential settlement poses safety hazards to vehicles traveling at high speeds, necessitating its control to enhance driving safety and comfort.

[0003] Uneven settlement is mainly caused by the difference in consolidation between the old and new roadbeds. Many highways have reached traffic saturation, making upgrades imperative. Roadbed widening is crucial in both design and construction. After years of operation, the original roadbed (old roadbed) has largely settled. If the junction between the old and new roadbeds is not properly treated, uneven settlement will inevitably lead to damage at this junction, severely compromising the quality of the highway.

[0004] In existing technologies, the main engineering techniques employed include excavation of existing road embankments in steps, reinforcement of the subgrade with geosynthetic materials and reinforced embankments, and geotextile seepage prevention and drainage. All of these techniques present challenges due to their complex construction. Furthermore, in the case of excavation of existing road embankments in steps, since workers excavate slopes on the original roadbed, the excavated platforms may not be as intended. Therefore, a device is needed to prevent differential settlement of the road. Summary of the Invention

[0005] To address the problems existing in the prior art, this invention provides a prestressed device and construction method for preventing differential settlement of roads, which can effectively reduce differential settlement between new and old roadbeds and improve vehicle driving safety and comfort.

[0006] The technical solution of the present invention is as follows:

[0007] In a first aspect of the invention, a prestressing device for preventing differential settlement of roads is provided, comprising a hollow threaded steel pipe, a prestressing module, a load-bearing module, and a stabilizing module disposed within a housing. The prestressing module and the load-bearing module are disposed outside the hollow threaded steel pipe, and the bottom of the hollow threaded steel pipe is connected to the stabilizing module. A grouting pipe is disposed on the load-bearing module and communicates with the hollow threaded steel pipe to form a load-bearing plate through grouting. A prestressing member is disposed on the prestressing module, and retaining springs are disposed at both ends of the prestressing member. The retaining springs are engaged with the hollow threaded steel pipe, and the prestress of the prestressing member is released by the opening of the upper retaining spring.

[0008] In some embodiments of the present invention, the grouting pipe includes a plurality of arc-shaped grouting pipes connected to a hollow threaded steel pipe and evenly arranged in the circumferential direction of the hollow threaded steel pipe, and the grouting pipe is provided with an grouting port.

[0009] In some embodiments of the present invention, the outer shell is made of steel, and a grouting pipe channel is provided on the steel outer shell at a position corresponding to the end of the grouting pipe.

[0010] In some embodiments of the present invention, the prestressed member is sleeved on the outside of the hollow threaded steel pipe and is separate from the hollow threaded steel pipe.

[0011] In some embodiments of the present invention, the two ends of the upper end retaining spring of the prestressed member are connected by steel cables. The upper end retaining spring rotates with the hollow threaded steel pipe and is pulled open by the steel cables, releasing the prestress of the prestressed member, while the lower end retaining spring continues to constrain the prestressed member.

[0012] In some embodiments of the present invention, the stabilizing module includes a pusher head, the upper end of which contacts a hollow threaded steel pipe and is temporarily fixed by a rope, and the lower end of the pusher head is provided with an anchor rod.

[0013] In some embodiments of the present invention, the lower end of the pusher head is tapered, and a plurality of anchor rods are provided on the lower end of the pusher head, the anchor rods and the lower end of the pusher head being connected by weld points.

[0014] In some embodiments of the present invention, the bottom of the outer casing is provided in a conical shape, and an anchor channel is provided at the steel outer casing corresponding to the end of the anchor rod.

[0015] In some embodiments of the present invention, the prestressed module and the load-bearing module form a component unit, and multiple component units can be set according to the required component length.

[0016] In a second aspect of the invention, a method for constructing a prestressed device to prevent differential settlement of roads is provided, comprising the following steps:

[0017] The prestressed device is embedded or pressed into the junction of the old and new roads and into the new road section;

[0018] Rotating the hollow threaded steel pipe allows the grouting pipe in the load-bearing module to extend into the soil, the prestressed components in the prestressed module to release prestress, and the anchor rods of the device stabilization module to extend.

[0019] During the rotation, continuously check the scale line at the top of the hollow threaded steel pipe. When the change of the scale line is equal to the height of the load-bearing module, it indicates that the grouting pipe has completed its maximum extension.

[0020] After checking the extension of the load-bearing module, grout is injected through hollow threaded steel pipes. After a period of time, the grout solidifies to form a load-bearing plate, and the construction process is completed.

[0021] One or more technical solutions of the present invention have the following beneficial effects:

[0022] (1) The prestressed device for preventing differential settlement of roads provided by the present invention includes a hollow threaded steel pipe, a prestressed module, a load-bearing module and a stabilizing module. The prestressed module replaces the gradually disappearing pore water pressure to transmit force to the upper load-bearing module to support the upper soil and prevent the upper soil from settling.

[0023] (2) The prestressed device for preventing differential settlement of roads provided by the present invention uses a hollow threaded steel pipe as the starting device of the whole device. By rotating, it drives the extension of the grouting pipe in the load-bearing module, the release of prestress in the prestressing module, and the extension of the anchor rod in the stabilizing module, so as to realize that the prestressed device can be firmly buried in the junction of the old and new roads and the new road section or the device can be pressed into the foundation from the junction of the old and new roads and the top of the new road subgrade.

[0024] (3) The prestressed device for preventing differential settlement of roads provided by the present invention, by setting an arc-shaped grouting pipe in the load-bearing module, can extend the arc-shaped grouting pipe into the soil for grouting under the rotation of the hollow threaded steel pipe, so that the surrounding soil forms a load-bearing plate, and the load-bearing plate provides support for the upper soil.

[0025] (4) The prestressed device for preventing differential settlement of roads provided by the present invention sets a prestressed component in the prestressed module and sets a retaining spring at the upper and lower ends of the prestressed component. The prestress of the prestressed component can be released by the traction of the upper retaining spring, while the lower retaining spring continues to constrain the prestressed component to develop downward, so as to provide good prestress for the whole device and enable it to transmit force to the load-bearing plate when settlement occurs.

[0026] (5) The prestressed device for preventing differential settlement of roads provided by the present invention is equipped with a stabilizing module, including a pusher, an anchor rod and a fixing plate. Through the special setting of the connection structure between each structure, when the pusher descends a certain distance, the anchor rod and the top of the pusher break at the weld point, the anchor rod recovers its shape and gets stuck in the one-way channel, providing support for the device and ensuring the vertical stability of the device. Attached Figure Description

[0027] Figure 1 This is a schematic diagram of the overall structure of the prestressed device for preventing differential settlement of roads according to the present invention.

[0028] Figure 2 This is a schematic diagram of the prestressed module of the present invention;

[0029] Figure 3 This is a structural schematic diagram of the load-bearing module of the present invention;

[0030] Figure 4 This is a schematic diagram of the structure of the stabilization module of the present invention.

[0031] In the diagram: 1. Hollow threaded steel pipe; 2. Prestressed module; 201. Prestressed component; 202. Upper end retaining ring; 203. Lower end retaining ring; 204. Steel cable; 3. Load-bearing module; 301. Grouting pipe; 302. Grouting port; 4. Stabilizing module; 401. Rope; 402. Hanging ring; 403. Push head; 404. Anchor bolt; 405. Weld point; 406. Fixing plate; 5. Outer shell; 501. Grouting pipe channel; 502. Push head fixing channel; 503. Anchor bolt channel. Detailed Implementation

[0032] The present invention will be further described below with reference to the accompanying drawings and embodiments.

[0033] Example 1

[0034] Uneven settlement is mainly caused by the difference in the degree of consolidation between the old and new roadbeds. Consolidation refers to the process by which soil porosity decreases, pore water pressure dissipates, and effective stress increases under its own weight or external loads.

[0035] Total soil stress = Effective stress + Pore water pressure

[0036] As can be seen from the above formula, consolidation is essentially the process of converting pore water pressure into effective stress. The greater the effective stress, the greater the compression, and consequently, the greater the settlement.

[0037] In a typical embodiment of the present invention, a prestressed device for preventing differential settlement of roads is proposed, such as... Figure 1-4 As shown, the invention includes a hollow threaded steel pipe 1, a prestressed module 2, a load-bearing module 3, and a stabilizing module 4, all housed within the outer casing 5. When settlement occurs, the prestressed module of this invention replaces the gradually disappearing pore water pressure to transmit force to the upper load-bearing module, supporting the upper soil and preventing settlement of the upper soil.

[0038] Specifically, the hollow threaded steel pipe 1 is fitted with a prestressed module 2 and a load-bearing module 3, and the bottom of the hollow threaded steel pipe 1 is connected to a stabilizing module 4; a grouting pipe 301 is installed on the load-bearing module 3, and the grouting pipe 301 is connected to the hollow threaded steel pipe 1 to form a load-bearing plate through grouting; a prestressed component 201 is installed on the prestressed module 2, and spring clips are installed at both ends of the prestressed component 201, and the prestress of the prestressed component is released by the opening of the upper spring clip 202.

[0039] The structure of the prestressed module is as follows Figure 2As shown, the device includes a retaining ring, a steel cable 204, and a prestressed member 201. The prestressed member is a hollow cylindrical structure. The prestressed member 201 is sleeved on the outside of the hollow threaded steel pipe 1, but is separate from the hollow threaded steel pipe 1 and will not rotate with the rotation of the hollow threaded steel pipe 1. An upper retaining ring 202 is provided on the upper part of the prestressed member 201, and a lower retaining ring 203 is provided on the lower part of the prestressed member 201. The prestressed member 201 is spaced a short distance from the lower load-bearing module 3. The weight of the prestressed member 201 is supported by the lower retaining ring 203, which also restricts the downward development of the prestressed member 201. The top of the prestressed member 201 is also spaced a short distance from the upper load-bearing module 3 to avoid premature force transmission. The prestress is constrained by the retaining rings at both ends. The upper retaining ring 202 is connected to the steel shell by steel cables 204. As the hollow threaded steel pipe 1 rotates, the upper retaining ring 202 is pulled open by the steel cables 204, and the prestress of the prestressed member 201 can be released. Meanwhile, the lower retaining ring 203 continues to constrain the prestressed member 201, limiting the downward development of the prestressed member.

[0040] In this embodiment, the upper retaining ring 202 and the lower retaining ring 203 are attached to the hollow threaded steel pipe 1 and maintain a short distance from the upper and lower ends of the prestressed member 201, respectively (short distance means close but not in contact, to avoid premature force transmission by the prestressed member). By limiting the displacement of the prestressed member 201, the control of the prestress is ensured, and the prestressed member is prevented from prematurely contacting and transmitting force to the load-bearing module 3. Therefore, the main function of the retaining ring is to bear the axial force. The lower retaining ring 203 mainly bears the weight and prestress of the prestressed member in the corresponding prestressing device, while the upper retaining ring 202 mainly bears the prestress.

[0041] The principle of the snap ring constraint and prestress release in this embodiment is as follows:

[0042] When constraining prestress, the upper retaining spring 202 is secured to the hollow threaded steel pipe 1, bearing the force from the prestressed member 201 and restricting its upward development, while also preventing it from contacting the upper load-bearing module to transmit prestress. The lower retaining spring 203 bears the weight and prestress of the prestressed member 201 and restricts its downward development. Since neither end of the prestressed member can achieve displacement, the prestress cannot be transmitted to the load-bearing module, thus constraining the prestress of the prestressed member.

[0043] Release of prestress: The upper retaining spring 202 and the outer shell 5 are connected by a steel cable 204. Due to the rotation of the hollow threaded steel pipe 1, the upper retaining spring 202 rotates with it. During this process, the steel cable 204 applies tension to the retaining spring 202, increasing the opening angle of the upper retaining spring. This reduces its ability to withstand axial force (i.e., the force applied by the prestressed member), eventually causing it to be unable to withstand the axial force. This results in the prestressed member 201 developing upwards, thereby releasing the prestress in the prestressed member 201.

[0044] The structure of load-bearing module 3 is as follows Figure 3 As shown, the grouting pipe 301 includes multiple arc-shaped grouting pipes connected to the hollow threaded steel pipe 1, and is evenly arranged in the circumferential direction of the hollow threaded steel pipe 1. The grouting pipe 301 is provided with multiple grouting ports 302. The outer shell 5 is made of steel. The steel shell is provided with grouting pipe channels 501 at positions corresponding to the ends of the grouting pipe 301. When the hollow threaded steel pipe rotates and moves downward, the grouting pipe 301 rotates with the rotation of the hollow threaded steel pipe 1. The grouting pipe 301 extends out of the outer shell 5 through the grouting pipe channels 501. Cement mortar is injected from the hollow threaded steel pipe 1 and pumped out into the soil through the grouting ports 302 of the grouting pipe 301, forming a load-bearing plate around the soil. In addition, the range of the load-bearing plate can be indirectly controlled by controlling the height of the load-bearing module 3 and the curvature of the grouting pipe 301.

[0045] The structure of stabilization module 4 is as follows: Figure 4 As shown, the stabilizing module 4 includes a pusher head 403. The upper end of the pusher head 403 contacts the hollow threaded steel pipe 1 and is temporarily fixed by a rope 401. Specifically, the rope 401 is used to wrap the upper end of the pusher head 403 and the bottom of the hollow threaded steel pipe 1 together (and tie a knot), filling the channel. The friction between the rope and the channel temporarily restricts the displacement of the pusher head and the hollow threaded steel pipe. In addition, to avoid insufficient friction to support the weight of the hollow threaded steel pipe 1 and the pusher head 403, the rope used for wrapping is knotted, and its two ends are taut and fixed to the hanging ring. The hanging ring is fixed to the outer shell to provide tension.

[0046] An anchor rod 404 is provided at the lower end of the pusher head. The upper end of the pusher head is cylindrical and installed in the pusher head fixing channel 502 of the housing, and can move up and down within the pusher head fixing channel. The lower end of the pusher head 403 is conical and located in the conical cavity of the housing. Multiple anchor rods 404 are provided on the lower end of the pusher head 403. The anchor rods 404 and the lower end of the pusher head 403 are connected by weld points 405, which serve as temporary fixation. The bottom of the outer shell 5 is conical. An anchor rod channel 503 is provided at the steel outer shell 5 corresponding to the end of the anchor rod 404. A fixing plate 406 is provided at the housing position where the anchor rod channel 503 is located. The fixing plate 406 is located on both sides of the anchor rod channel 503 and serves as a guide for the movement of the anchor rod. In the initial state, the free end (i.e., the non-welded end) of the anchor rod rests on the fixing plate 406. When the pusher head moves downward, the anchor rod extends out from the anchor rod channel 503 along the angle of the fixing plate 406. Driven by the hollow threaded steel pipe 1, the rope 401 breaks, and the lower end of the pusher 403 descends continuously, pushing the lower end of the anchor rod 404 completely out of the anchor rod channel 503. The fixing plate positions the movement of the anchor rod 404, ensuring that it can extend along the fixed anchor rod channel 503. During the movement, the anchor rod 404 experiences horizontal and vertical displacement, meaning that the anchor rod 404 will generate a certain curvature. After descending a certain distance, the anchor rod and the top of the pusher break brittlely at the weld point, the anchor rod recovers its shape, and is stuck in the anchor rod channel, reinforcing the surrounding soil and providing support for the device, ensuring the vertical stability of the device. At this time, the fixing plate 406 can also increase the stress-bearing area of ​​the extended anchor rod on the stabilizing module and avoid stress concentration on the anchor rod and mutual interference between anchor rods inside the device. In addition, when the anchor rod encounters rock, under the action of thrust, the anchor rod will also break brittlely at the weld point and slide upward, ensuring the normal extension of other anchor rods.

[0047] In this embodiment, the prestressed module 2 and the load-bearing module 3 form a component unit, and multiple component units can be set according to the required component length to meet the actual needs of different projects.

[0048] In this embodiment, the hollow threaded steel pipe 1 is the starting device for the entire apparatus. By rotating, it drives the extension of the grouting pipe in the load-bearing module, the release of prestress in the prestressing module, and the extension of the anchor rod in the stabilizing module. In addition, the top of the hollow threaded steel pipe is equipped with a scale line to detect the extension of the load-bearing module.

[0049] In use, the prestressed device provided in this embodiment is embedded at the junction of the old and new roads and in the new road section, or it is pressed into the foundation from the top of the roadbed at the junction of the old and new roads and the new road. After the prestressed device enters the foundation, the hollow threaded steel pipe is rotated, causing the grouting pipe in the load-bearing module to extend in the soil, the prestressed components in the prestressed module to release prestress, and the anchor rods of the stabilizing module to extend. During the rotation, the scale line at the top of the hollow threaded steel pipe is continuously checked. When the change in the scale line is equal to the height of the load-bearing module, it indicates that the grouting pipe has completed its maximum extension. After checking the extension of the load-bearing module, grout is injected through the hollow threaded steel pipe. After a period of time, the grout solidifies to form a load-bearing plate, and the construction process is completed.

[0050] When settlement occurs, the prestressed modules of the prestressed device replace the gradually disappearing pore water pressure to transmit force to the upper load-bearing modules to support the upper soil and prevent the upper soil from settling.

[0051] Example 2

[0052] In a typical embodiment of the present invention, a construction method for a prestressed device to prevent differential settlement of roads is provided, comprising the following steps:

[0053] The prestressed device is embedded or pressed into the junction of the old and new roads and into the new road section;

[0054] Rotating the hollow threaded steel pipe allows the grouting pipe in the load-bearing module to extend into the soil, the prestressed components in the prestressed module to release prestress, and the anchor rods of the device stabilization module to extend.

[0055] During the rotation, continuously check the scale line at the top of the hollow threaded steel pipe. When the change of the scale line is equal to the height of the load-bearing module, it indicates that the grouting pipe has completed its maximum extension.

[0056] After checking the extension of the load-bearing module, grout is injected through hollow threaded steel pipes. After a period of time, the grout solidifies to form a load-bearing plate, and the construction process is completed.

[0057] While the specific embodiments of the present invention have been described above in conjunction with the accompanying drawings, this is not intended to limit the scope of protection of the present invention. Those skilled in the art should understand that various modifications or variations that can be made by those skilled in the art without creative effort based on the technical solutions of the present invention are still within the scope of protection of the present invention.

Claims

1. A prestressed device for preventing differential settlement of roads, characterized in that, The device includes a hollow threaded steel pipe, a prestressed module, a load-bearing module, and a stabilizing module, all housed within a casing. The hollow threaded steel pipe is fitted with the prestressed module and the load-bearing module, and the bottom of the hollow threaded steel pipe is connected to the stabilizing module. A grouting pipe is installed on the load-bearing module and communicates with the hollow threaded steel pipe to form a load-bearing plate through grouting. A prestressed component is installed on the prestressed module, and spring clips are installed at both ends of the prestressed component. The spring clips are secured to the hollow threaded steel pipe, and the prestress of the prestressed component is released when the upper spring clips open. When settlement occurs, the prestressed modules replace the gradually disappearing pore water pressure to transmit force to the upper load-bearing modules to support the upper soil and prevent the upper soil from settling. A short distance is reserved between the top of the prestressed member and the upper load-bearing module to avoid premature force transmission; The grouting pipe includes multiple arc-shaped grouting pipes connected to a hollow threaded steel pipe, and they are evenly arranged in the circumferential direction of the hollow threaded steel pipe. The grouting pipe is provided with an injection port. The outer shell is made of steel, and grouting pipe channels are set on the steel shell at positions corresponding to the ends of the grouting pipes.

2. The prestressed device for preventing differential settlement of roads as described in claim 1, characterized in that, The prestressed member is sleeved on the outside of the hollow threaded steel pipe and is separate from the hollow threaded steel pipe.

3. The prestressed device for preventing differential settlement of roads as described in claim 1, characterized in that, The two ends of the upper retaining spring of the prestressed member are connected by steel cables. The upper retaining spring rotates with the hollow threaded steel pipe and is pulled open by the steel cables, releasing the prestress of the prestressed member, while the lower retaining spring continues to constrain the prestressed member.

4. The prestressed device for preventing differential settlement of roads as described in claim 1, characterized in that, The stabilization module includes a pusher head, the upper end of which contacts a hollow threaded steel pipe and is temporarily fixed by a rope, and the lower end of the pusher head is provided with an anchor rod.

5. The prestressed device for preventing differential settlement of roads as described in claim 4, characterized in that, The lower end of the pusher head is tapered, and multiple anchor rods are provided on the lower end of the pusher head. The anchor rods and the lower end of the pusher head are connected by weld points.

6. The prestressed device for preventing differential settlement of roads as described in claim 5, characterized in that, The bottom of the outer shell is tapered, and an anchor channel is provided at the steel outer shell corresponding to the end of the anchor rod.

7. The prestressed device for preventing differential settlement of roads as described in claim 1, characterized in that, The prestressed module and the load-bearing module form a component unit, and multiple component units can be set according to the required component length.

8. A construction method for a prestressed device for preventing differential settlement of roads as described in any one of claims 1-7, characterized in that, Includes the following steps: The prestressed device is embedded or pressed into the junction of the old and new roads and into the new road section; Rotating the hollow threaded steel pipe allows the grouting pipe in the load-bearing module to extend into the soil, the prestressed components in the prestressed module to release prestress, and the anchor rods of the device stabilization module to extend. During the rotation, continuously check the scale line at the top of the hollow threaded steel pipe. When the change of the scale line is equal to the height of the load-bearing module, it indicates that the grouting pipe has completed its maximum extension. After checking the extension of the load-bearing module, grout is injected through hollow threaded steel pipes. After a period of time, the grout solidifies to form a load-bearing plate, and the construction process is completed.

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