Cement concrete pavement void treatment method

Abstract

The invention relates to pavement construction, and provides a cement concrete pavement void treatment method which comprises the following steps: positioning a void position below a pavement slab; a sand filling channel is formed in the position, corresponding to the disengagement, of the pavement slab; hard sand grains are filled into the void along the sand filling channel; vibrating the pavement slab by adopting a vibrating machine, so that the hard sand grains in the void are compactly filled; a glue pouring guide pipe is inserted into the sand pouring channel to the bottom of the cavity, and an adhesive is poured into the cavity along the glue pouring guide pipe until the adhesive does not flow any more; and the glue filling guide pipe is pulled out, and after the hard sand grains and the adhesive are maintained, a waterproof material is sprayed and injected to the top of the sand filling channel. The hard sand grains which are filled into the void and vibrated serve as a primary support of the pavement slab, an adhesive is poured into the hard sand grains to enable the hard sand grains to be bonded together to form a complete supporting structure, and then a waterproof material is sprayed to prevent rainwater from invading, so that the use performance of the pavement slab is improved.

Description

Technical Field

[0001] The invention belongs to the technical field of pavement construction and discloses a method for treating voids in a cement concrete pavement. Background Art

[0002] At present, cement concrete pavement is widely used in my country. However, cement concrete pavement is prone to slab bottom debonding. If it is not identified and treated in time, the performance of the pavement will inevitably be reduced. The main factors causing slab bottom debonding are plastic deformation of slab bottom materials, scouring and pumping of rainwater, weak links in structural design, and untimely maintenance and repair. After the slab bottom is debonded, its stress condition is extremely unfavorable and other forms of damage are likely to occur.

[0003] Appropriately increasing the thickness of cement concrete road panels is an effective way to extend the service life of the road surface, but it will increase the cost of the road construction. At present, the treatment of slab bottom voids mainly adopts grouting reinforcement method, which uses hydraulic, air pressure or electrochemical principles to evenly inject the reinforcement slurry into the base through the grouting pipe, and drives away the moisture and gas between the base particles by filling, infiltration or compaction. After filling and hardening, the base particles become a whole, forming a new base with high strength, low compressibility, high impermeability and good stability. However, there are the following problems: 1) The slabs treated with grouting will produce new radial cracks with sealing as the core, and the plate corners will warp when lifting the dislocated and sinking slabs; 2) The slurry distribution is not dense, which is easy to produce stress concentration points, forming table leg support and new gaps; 3) It has high requirements for construction equipment and construction technology, complex process, long construction period, low material performance and low cost performance. Summary of the invention

[0004] In order to overcome the deficiencies in the prior art, the present invention provides a method for treating voids in a cement concrete pavement to improve the performance of the pavement.

[0005] To achieve the above object, the present invention adopts the following technical solutions: A method for treating voids in a cement concrete pavement comprises the following steps: S1. Locate the empty space under the road slab; S2. Open a sand filling channel at the corresponding position of the gap on the pavement slab; S3, filling hard sand into the hollow space along the sand filling channel; S4. Use a vibrating machine to vibrate the road slab to fill the hollow hard sand particles densely; S5, inserting a glue injection conduit into the sand injection channel to the bottom of the degassing cavity, and injecting adhesive into the degassing cavity along the glue injection conduit until the adhesive stops flowing; S6. Pull out the glue injection tube, cure the hard sand and adhesive, and then pour waterproof material on the top of the sand injection channel.

[0006] It should be noted that in S1, a Beckmann beam deflection detector is used to locate the void position under the road slab.

[0007] It should be noted that in S2, when voids occur at the corners or joints of the road panels, the cleaned joints are used as sand filling channels.

[0008] It should be noted that in S2, when the void occurs in the middle of the pavement panel, a hole is drilled in the pavement panel as a sand filling channel, and the diameter of the drill hole is 3-5 cm.

[0009] It should be noted that in S3, the hard sand particles are one or more of quartz sand, diabase, basalt, and river sand, preferably river sand; and the particle size is 2-3 mm.

[0010] It should be noted that, in S4, the vibrating machine is a walk-behind vibrating roller.

[0011] It should be noted that in S5, the glue-filling catheter comprises an outer sleeve and an inner sleeve sleeved inside the outer sleeve, the side wall of the outer sleeve is provided with a plurality of through holes, and the bottom is a cone tip; the bottom of the inner sleeve is an opening.

[0012] It should be noted that, in S5, the adhesive is a two-component epoxy structural adhesive.

[0013] It should be noted that, in S6, the waterproof material adopts a single-component polyurethane waterproof coating.

[0014] The technical principle of the present invention is as follows: after a large number of field investigations, it was found that most of the voids were caused by water damage at the joints. There were phenomena of obvious joints being pulled apart, or even plate sinking and dislocation, and depressions appeared in the foundation at the joints; the voids at the corners of the plates were the main reason for the rapid development of the disease. First, by cutting and cleaning the foreign matter in the joints, a channel leading to the void is formed. Through the channel, clean and dry hard sand particles (such as river sand) with a particle size of 2-3mm are poured into the void. The poured hard sand particles can fill the void under the road slab, and at the same time, the void is filled densely through vibration to complete the initial support; then, epoxy structural glue is poured into the hard sand particles to fully wet the hard sand particles filled in the void, and through chemical reactions, the hard sand particles in the void are completely consolidated to form a hard support; finally, waterproof materials are poured on the surface of the hard sand particles to complete the waterproof treatment of the joints or drilled holes, prevent rainwater from infiltrating, and avoid the recurrence of voids.

[0015] Compared with the prior art, the present invention has the following beneficial technical effects: By filling sand and vibrating, the hard sand particles are filled into the voids to reach a full and dense level, which can effectively reduce the gaps in the voids. The vibrated hard sand particles serve as the initial support for the road slabs in the void area. Then, the hard sand particles are bonded together by pouring adhesive to form a complete supporting structure for the road slabs in the void area. The structure has strong bonding strength and supporting capacity. Waterproof material is poured on the surface of the structure for waterproofing, thereby improving the durability of the structure and ensuring its performance. BRIEF DESCRIPTION OF THE DRAWINGS

[0016] Figure 1 Schematic diagram of filling the hollow position with sand.

[0017] Figure 2 Schematic diagram of injecting adhesive into the hollow position.

[0018] Figure 3 Schematic diagram of pouring waterproof material.

[0019] In the figure: road panel 1; foundation 2; hollowing 3; river sand 4; adhesive 5; waterproof material 6. DETAILED DESCRIPTION

[0020] The technical solution of the present invention will be described clearly and completely below.

[0021] The hollowing out of the bottom of the slab caused by water damage is the main cause of road damage. Due to the problems of traditional treatment effect and treatment cost, all hollowing diseases cannot be effectively and timely treated, resulting in rapid development of the disease, greatly accelerating the damage of the road surface and shortening the service life of the road surface. In short, the hollowing out of the bottom of the slab is a disease that seriously affects the performance of concrete pavement and threatens the service life, and should be taken seriously. Actively study the laws of diseases, find new materials and construction processes, carefully construct, standardize maintenance, take timely measures to effectively treat the cement concrete panels with hollowing out of the bottom of the slab, and combine the actual project to simplify the construction process as much as possible, reduce construction costs, improve treatment efficiency, and consolidate and stabilize river sand. This goal has basically been achieved, which has very good practical significance for highway construction and maintenance.

[0022] See also Figure 1-3 ; This embodiment provides a method for treating voids in a cement concrete pavement, comprising the following steps: S1. Locate the empty space under the road slab; The Beckman beam deflection detector is used to locate the void position under the road slab; by testing the deflection value of the slab corners (40cm from the transverse joint and 10cm from the longitudinal joint) one by one, it is determined whether the bottom of the slab is void. When the deflection of the slab corner is greater than 12 (0.01mm), it is considered that there is a void and the void position is marked.

[0023] S2. Open a sand filling channel at the corresponding position of the gap on the pavement slab; The bottom of the slab is mainly hollowed out at the corners of the road slab and adjacent joints. Through cutting and other means, remove the joint materials and foreign matter such as mud and sand in the joints near the hollow area; use the cleaned joints as sand filling channels; For the voids in the center area of ​​the road slab, holes can be drilled on the road slab as sand filling channels. The diameter of the holes should be 3-5cm and the depth should be the thickness of the road slab. After the sand filling channels are opened, an air compressor should be used to remove debris and dust from the holes.

[0024] When opening a sand filling channel, the sand filling channel can be cleaned using tools such as endoscopes, hooks, electric hammers, industrial vacuum cleaners, etc. to ensure smooth flow of the sand filling channel.

[0025] S3, filling hard sand into the hollow space along the sand filling channel; Clean, dry, hard sand with a particle size of 2-3 mm is poured into the cleaned sand filling channel. The particles are uniform and round, and the hard sand is river sand.

[0026] S4. Use a vibrating machine to vibrate the road slab to fill the hollow hard sand particles densely; The vibration machine adopts a hand-held vibratory roller, such as the YL600A model, with a vibration frequency of 70Hz and a weight of 1t. In the process of pouring river sand into the de-emptied area, the river sand always accumulates in the de-emptied area according to the natural accumulation angle. When the river sand first fills the joints or drilled holes, the vibratory roller is turned on to vibrate the road panel, and the road panel transfers the vibration load to the river sand. The river sand accumulated at the joints or drilled holes gradually moves to the gaps in the de-emptied area that are not filled with river sand under the action of the vibration load. When all the gaps in the de-emptied area are filled, continue to vibrate until the river sand in the joints or drilled holes no longer leaks, and continue to vibrate for 3-5 minutes. The present invention achieves the purpose of quickly filling the de-emptied depression with river sand by vibrating the road panel.

[0027] In addition, in other implementations, equipment such as vibrating rods, compactors, and vibratory rollers may be used to compact the hard sand particles. The main purpose is to ensure the filling and compact quality of the sand while not damaging the original road slab and the foundation underneath it.

[0028] S5, inserting a glue injection conduit into the sand injection channel to the bottom of the degassing cavity, and injecting adhesive into the degassing cavity along the glue injection conduit until the adhesive stops flowing; The glue-filling conduit includes an outer sleeve and an inner sleeve sleeved in the outer sleeve. The side wall of the outer sleeve is provided with a number of through holes, and the bottom is a cone tip; the bottom of the inner sleeve is an opening; the glue-filling conduit is inserted into the river sand until the bottom is emptied, and the conduit is pulled out 3-5cm upward; in actual operation, a solid sleeve rod needs to be inserted into the glue-filling conduit to be more stressed. When the glue-filling conduit is inserted to the preset position, the solid sleeve rod in the glue-filling conduit is pulled out, and then the adhesive is poured into the inner sleeve of the glue-filling conduit. The glue-filling conduit will first flow to the bottom opening of the inner sleeve, and then gradually flow to the gap between the inner sleeve and the outer sleeve, and then flow into the river sand through the through holes on the outer sleeve. The adhesive uses a two-component epoxy structural adhesive. The initial state of the two-component epoxy structural adhesive is liquid, which can flow in the river sand. The operation period is greater than 2h (25℃), and the permeability is good in 2-3mm river sand. The compressive strength of the consolidated body formed after consolidating the river sand for 24h (25℃) is greater than 90MPa.

[0029] In addition, you can also use a probe to detect whether there is adhesive at the bottom of the hollow 10-15cm away from both sides of the glue pouring tube. Insert the probe vertically into the river sand, pull out the probe, and then sprinkle river sand on the probe. From the length of the sand stuck to the probe, we can detect the depth of epoxy structural glue infiltration. When the depth exceeds the bottom of the panel, stop pouring.

[0030] S6. Pull out the glue injection conduit, and after curing the hard sand and adhesive, pour waterproof material on the top of the sand injection channel; After 12-24 hours of maintenance, waterproof material is poured on the surface of the joints or drilled holes to seal them. The waterproof material uses a single-component polyurethane waterproof coating, which meets the quality standards of polyurethane room-temperature construction fillers in "JTGF30-2014 Technical Specifications for Highway Cement Concrete Pavement Construction".

[0031] In addition, in other implementations, other waterproof materials may also be used, which can be convenient for construction and have a significant waterproof effect.

[0032] Within 3 days after the completion of the consolidation and stabilization of the river sand at the bottom of the slab, the Beckman beam deflection detection method is used to re-measure the deflection of the road slab to check whether the support effect is qualified. If it does not meet the requirements, the ground penetrating radar can be used to accurately find the void points and perform supplementary treatment until the design quality requirements are met. The supplementary treatment is carried out according to the aforementioned drilling, sand filling, glue filling and other processes.

[0033] In summary. First, by removing and cleaning foreign objects in the joints, a sand filling channel leading to the void is formed. Through this channel, clean and dry hard sand particles (such as river sand) with a particle size of 2-3mm are poured into the void. The poured hard sand particles can fill the void under the road slab, and at the same time, the void is filled and compacted through vibration to complete the initial support; then, epoxy structural adhesive is poured into the hard sand particles to fully wet the hard sand particles filled in the void, and through chemical reactions, the hard sand particles in the void are completely consolidated to form a hard support; finally, waterproof material is poured on the surface of the hard sand particles to complete the waterproof treatment of the joints or drilled holes, prevent rainwater from seeping in, and avoid the recurrence of voids.

[0034] The above description is only used to illustrate the technical solution of the present invention and is not intended to limit it. Any modification or replacement of the technical solution made by other technicians in this professional field should be included in the scope of the claims of the present invention as long as it does not deviate from the connotation of the technical solution of the present invention.

Claims

1. A method for treating voids in a cement concrete pavement, characterized in that: The steps include: S1. Locate the empty space under the road slab; S2. Open a sand filling channel at the corresponding position of the gap on the pavement slab; S3, filling hard sand into the hollow space along the sand filling channel; S4. Use a vibrating machine to vibrate the road slab to fill the hollow hard sand particles densely; S5, inserting a glue injection conduit into the sand injection channel to the bottom of the degassing cavity, and injecting adhesive into the degassing cavity along the glue injection conduit until the adhesive stops flowing; S6. Pull out the glue injection tube, cure the hard sand and adhesive, and then pour waterproof material on the top of the sand injection channel.

2. The method according to claim 1, characterized in that: In S1, the Beckmann beam deflection detector is used to locate the void under the road slab.

3. The method according to claim 1, characterized in that: In S2, when voids occur at the corners or joints of the road panels, the cleaned joints are used as sand filling channels.

4. The method according to claim 1, characterized in that: In S2, when the void occurs in the middle of the pavement slab, a hole is drilled in the pavement slab as a sand filling channel, and the diameter of the drill hole is 3-5 cm.

5. The method according to claim 1, characterized in that: In S3, the hard sand particles are one or more of quartz sand, diabase, basalt, and river sand, and the particle size is 2-3 mm.

6. The method according to claim 1, characterized in that: In S4, the vibrating machine is a walk-behind vibrating roller.

7. The method according to claim 1, characterized in that: In S5, the glue-filling conduit comprises an outer sleeve and an inner sleeve sleeved inside the outer sleeve, the side wall of the outer sleeve is provided with a plurality of through holes, and the bottom is a cone tip; the bottom of the inner sleeve is an opening.

8. The method according to claim 1, characterized in that: The adhesive is a two-component epoxy structural adhesive.

9. The method according to claim 1, characterized in that: In S6, the waterproof material adopts a single-component polyurethane waterproof coating.

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