Construction method for preventing cracking of cement concrete pavement with asphalt concrete

Abstract

The present invention discloses a method for preventing cracking of cement concrete pavement by adding asphalt concrete, comprising the following steps: construction of pavement base layer; adding measures to prevent uneven settlement of the base layer; construction of cement concrete pavement; cutting of cement concrete pavement; grouting of cement concrete pavement; construction of curbstones; paving of reinforced asphalt concrete pavement; cutting of asphalt concrete pavement; grouting of asphalt concrete pavement. Compared with the prior art, the method of the present invention is not only highly operable, convenient and reliable, but also effectively reduces cracking of the pavement due to various reasons. The permanent and temporary combined roads at the construction site save a series of costs such as demolition and reconstruction, and the maintenance cost of the pavement in the later stage is also greatly reduced. Since the existing pavement is used as the base layer of the new pavement, the construction period is shortened. Compared with cement concrete pavement, the dust suppression and noise reduction functions of asphalt pavement are significantly improved, which has a better effect on protecting the surrounding environment.

Description

Technical Field

[0001] The present invention relates to the technical field of road engineering, in particular to a method for preventing cracks of cement concrete pavement after paving with asphalt concrete. Background Art

[0002] With the development of my country's economy, traffic volume has generally increased. Older roads are mostly pavemented with cement concrete, especially temporary roads within construction sites. Considering the heavy load requirements of construction vehicles, these roads are often paved with cement concrete. However, as traffic times increase, the comfort and durability of cement concrete pavements decrease significantly. With the country's increasing environmental protection requirements, the maintenance and repair costs of cement concrete pavements are also increasing. To improve the comfort and environmental performance of the road, an asphalt concrete surface layer is added to the cement concrete pavement, commonly known as "white to black" pavement conversion. The presence of reflective cracks in old concrete pavements significantly reduces the quality of the conversion. Therefore, the key to "white to black" projects lies in preventing reflective cracks.

[0003] Currently, a common approach to concrete pavement renovation involves excavating the entire surface layer of the old concrete pavement or removing any severely damaged base layer, replacing it with a lower-grade concrete or cement-stabilized gravel base layer, and then laying an asphalt concrete surface layer. While this structure can address the issues of crack reflection and uneven deformation after concrete pavement renovation to a certain extent, the renovation requires extensive construction, making it difficult to fully utilize the old pavement materials and resulting in high construction costs. A cement pavement blackening treatment structure already exists, comprising a rigid reinforcement strip, rigid cams, rivets, flexible filler, "inverted trapezoidal" openings, geogrids, grouting pipes, a base layer, an asphalt mixture surface layer, and cement slabs. While this structure addresses the crack reflection issue by incorporating a rigid reinforcement strip, which increases the difficulty of crack reflection, it fails to address the issues of improving the overall pavement structure, reusing old road materials, and prefabricated construction of medians. Summary of the Invention

[0004] In order to solve the above technical problems, the present invention provides a method for preventing cracks in cement concrete pavement by adding asphalt concrete, which can reduce the occurrence of cracks, facilitate later pavement maintenance, reduce the repair and maintenance area and thus reduce maintenance costs.

[0005] To achieve this technical purpose, the present invention adopts the following scheme:

[0006] A method for preventing cracking of cement concrete pavement by paving asphalt concrete comprises the following steps:

[0007] Step 1: Construction of road base;

[0008] Step 2: Add measures to prevent uneven settlement at the base layer;

[0009] Step 3: Cement concrete pavement construction;

[0010] Step 4: Cement concrete pavement cutting;

[0011] Step 5: Filling the cement concrete pavement;

[0012] Step 6: Curb construction;

[0013] Step 7: paving reinforced asphalt concrete pavement;

[0014] Step 8: Cutting the asphalt concrete pavement;

[0015] Step 9: Fill the joints of asphalt concrete pavement.

[0016] Furthermore, in step 1, the road surface base is a granular base, the specific type of which is not limited, and a degradable soil solidifier is used for base treatment.

[0017] Furthermore, the measures to prevent uneven settlement in step 2 are: setting steel plates or concrete pads with high shear strength at the bottom of the transverse joints of the concrete pavement to prevent uneven settlement of adjacent slabs.

[0018] Furthermore, during the concrete pavement construction process in step three, tie rods and force transfer rods are set at the expansion joints and contraction joints of the pavement, and steel reinforcement mesh is set at the false joints where no force transfer rods are set. After the concrete pavement construction is completed, maintenance work is carried out.

[0019] Furthermore, the caulking material in step five is a light-curing caulking material.

[0020] Furthermore, in step six, the location of the cement concrete pavement cut is marked on the curb.

[0021] Furthermore, after the asphalt concrete pavement is paved in step seven, an adjustable ultraviolet irradiation lamp is used to irradiate the asphalt surface layer.

[0022] Furthermore, the cutting position of the asphalt concrete pavement in step eight is consistent with the cutting position of the cement concrete pavement.

[0023] Compared with the prior art, the present invention has the following beneficial effects:

[0024] 1. Using a degradable soil solidifier for base treatment improves the physical and chemical properties of the soil, enhancing the durability and compressive strength of the road base, thereby preventing cracking in the superstructure and reducing long-term road maintenance costs. Furthermore, the degradable soil solidifier can be adjusted to achieve the optimal curing effect based on different soil types and environmental conditions. This makes it widely applicable in various geographical and climatic conditions, adapting to the road construction needs of different regions.

[0025] 2. Steel plates or concrete pads with high shear strength installed on the base can effectively reduce the uneven settlement between cement concrete slabs and avoid pavement cracking caused by shear stress.

[0026] 3. Install steel reinforcement mesh in the false joints where force transmission bars are not installed to increase the tensile strength of concrete and reduce the occurrence of cracks in concrete due to drying shrinkage, temperature changes, etc. The steel mesh forms a grid in the concrete, dispersing the stress and making it more difficult for cracks to penetrate the entire structure.

[0027] 4. Choose light-curing caulking materials. Compared with traditional asphalt caulking, light-curing caulking materials are superior in construction efficiency, environmental protection, durability, waterproofness, elasticity, etc. Compared with asphalt caulking, light-curing caulking materials are more effective in waterproofing, preventing rainwater from flowing into the foundation through the gaps and damaging the foundation.

[0028] 5. The adjustable UV lamp can precisely control the intensity and temperature of UV rays, effectively promoting the cross-linking reaction of chemical components in asphalt, enhancing the hardness and heat resistance of asphalt, and thus improving the comprehensive performance of the asphalt surface layer. At the same time, the adjustable system can avoid aging caused by excessive exposure.

[0029] 6. Before paving the asphalt concrete surface layer, mark the cutting position of the cement concrete pavement on the curbstone. The cutting position should be consistent so that the stress can be concentrated at the design position and the cracks can develop along the cut gaps.

[0030] 7. During the later maintenance of asphalt concrete pavement, when the cracks pass through the grouting material in the pre-cut joints of the asphalt concrete surface layer, the cracks can be re-filled, which greatly reduces the maintenance cost of the asphalt concrete surface layer and improves the efficiency of pavement maintenance.

[0031] In summary, the present invention increases the durability and compression resistance of the base layer by adding a degradable curing agent to the base layer; and also provides a steel plate or a concrete pad with strong shear resistance to effectively solve the cracks caused by the uneven settlement of the cement concrete slab; and provides a steel reinforcement mesh at the contraction joint position where no force transmission rod is provided, thereby improving the concrete stiffness and crack resistance at the contraction joint position; and rationally utilizes ultraviolet rays to promote the chemical reaction between asphalt and mineral materials, thereby accelerating the curing speed and enhancing the asphalt's crack resistance. Finally, pre-cut seams are provided on the asphalt concrete surface layer so that the inevitable cracks develop at the position of the pre-cut seams, which can effectively reduce the subsequent maintenance costs. The temporary road at the construction site is combined with the permanent road, which not only saves the need for the removal of the temporary pavement and the re-construction of the new pavement base, greatly saving the construction cost, but also effectively retains the bearing capacity of the temporary road at the construction site. The present invention can be widely used in the construction site for the overlay of asphalt concrete on the cement concrete pavement of the permanent and temporary combined road. BRIEF DESCRIPTION OF THE DRAWINGS

[0032] Figure 1 Schematic diagram of an embodiment of the present invention;

[0033] Figure 2 for Figure 1 Enlarged view of part A;

[0034] The markings in the figure are: 1. Roadbed; 2. Pavement base; 3. Cement concrete pavement; 4. Asphalt concrete pavement lower layer; 5. Asphalt concrete pavement upper layer; 6. Steel plate; 7. Steel reinforcement mesh; 8. Grouting material. DETAILED DESCRIPTION

[0035] In order to fully understand the purpose, features and effects of the present invention, the present invention is described in detail through the following specific embodiments, but the present invention is not limited thereto.

[0036] See also Figures 1 to 2 The present invention provides a technical solution: a method for preventing cracking of cement concrete pavement with asphalt concrete, comprising the following steps:

[0037] Step 1: Construction of road base 2

[0038] The road surface base 2 is a granular base, the specific type of which is not limited, and a degradable soil solidifier is used for base treatment.

[0039] Using degradable soil stabilizers for base treatment can improve the physical and chemical properties of the soil, enhancing the durability and compressive strength of the road's subgrade layer, thereby preventing cracking in the superstructure and reducing long-term road maintenance costs. Furthermore, degradable soil stabilizers can be tailored to specific soil types and environmental conditions to achieve optimal curing results. This makes them widely applicable across various geographical and climatic conditions, adapting to the road construction needs of diverse regions.

[0040] Step 2: Add measures to prevent uneven settlement at the base

[0041] Deepen the road construction drawings, lay out the cutting positions in advance, and reserve steel plates 6 or concrete pads with high shear strength in the cutting joints to prevent uneven settlement between the three slabs of cement concrete pavement and avoid pavement cracking caused by shear stress.

[0042] Step 3: Construction of cement concrete pavement 3

[0043] During the construction process, according to the design drawings and the requirements of the specifications, during the construction of the cement concrete pavement 3, tie rods and force transfer rods are set in the expansion joints and contraction joints of the pavement according to the requirements of the specifications, and the tie rods and force transfer rods are protected against corrosion as required. The tie rods and force transfer rods can effectively reduce the shrinkage cracking of the cement concrete pavement 3. A steel reinforcement mesh 7 is set in the contraction joint for the false joint position where no force transfer rod is set. After the construction of the cement concrete pavement 3 is completed, maintenance work is carried out. The transverse contraction joint cut at this position is usually a false joint, and the depth is 1 / 4 of the plate thickness. During conventional construction, the contraction joint position is prone to cracking into a through joint. For this reason, a single-layer, bidirectional steel reinforcement mesh 7 with a spacing of 200mm is set at the uncut 3 / 4 plate thickness position. The longitudinal and transverse steel bars are set vertically, the transverse steel bars are parallel to the contraction joint, and the longitudinal steel bars extend 500mm on each side of the false joint.

[0044] Steel reinforcement mesh 7 is installed at the false joints where force transmission bars are not installed to increase the tensile strength of concrete and reduce the occurrence of cracks in concrete due to drying shrinkage, temperature changes, etc. The steel reinforcement mesh 7 forms a grid in the concrete, dispersing stress and making it more difficult for cracks to penetrate the entire structure.

[0045] Step 4: Cement concrete pavement 3 cutting

[0046] According to the detailed drawings and previous layout records, the cement concrete pavement 3 is cut with a width of 3~8mm and a depth of 50mm. The cement concrete pavement 3 is cut when it reaches more than 25% of the design strength. Generally, the principle is not to damage the cement concrete pavement 3.

[0047] Step 5: Cement concrete pavement 3 filling

[0048] Before grouting, the cut gap should be cleaned and filled with grouting material 8. The grouting material 8 is a light-curing grouting material. After the grouting is completed, corresponding light is used to achieve rapid curing.

[0049] Caulking Material 8 uses a light-curing caulking material. Compared to traditional asphalt caulking, light-curing caulking material is superior in construction efficiency, environmental friendliness, durability, waterproofness, and elasticity. Furthermore, compared to asphalt caulking, light-curing caulking material provides a more effective waterproofing effect, preventing rainwater from flowing through cracks and damaging the foundation.

[0050] Step 6: Curb Construction

[0051] According to the design requirements of the drawings, the curbstones are constructed. After the curbstones are constructed, the positions of the 3 cuts in the cement concrete pavement are marked on the curbstones.

[0052] Step 7: Paving reinforced asphalt concrete pavement

[0053] The asphalt concrete pavement lower layer 4 is paved on the cement concrete pavement 3, and the asphalt concrete pavement upper layer 5 is further paved. If needed, a layer of special UV curing material is coated on the pavement. Then, the adjustable UV lamp is placed at a proper distance from the pavement, and the lamp is kept moving evenly above the pavement to ensure that the entire pavement is evenly irradiated with UV rays.

[0054] The adjustable UV lamp can precisely control the intensity and temperature of UV rays, effectively promoting the cross-linking reaction of chemical components in asphalt, enhancing the hardness and heat resistance of asphalt, and thus improving the overall performance of the asphalt surface layer. At the same time, the adjustable system can avoid aging caused by excessive exposure.

[0055] Step 8: Cutting the asphalt concrete pavement

[0056] According to the marks on the curb, cut the asphalt concrete pavement. The cutting position must be consistent with the cutting position of the cement concrete pavement. In this way, the stress can be concentrated at the position required by the design, and the cracks can be developed along the cut gaps.

[0057] Step 9: Fill the gaps in the asphalt concrete pavement. After cleaning the gaps, use the grouting material 8 to fill the gaps into place.

[0058] During the later maintenance of the asphalt concrete pavement, when the cracks pass through the caulking material 8 in the pre-cut seams of the asphalt concrete surface layer, the cracks can be re-caulked, which greatly reduces the maintenance cost of the asphalt concrete surface layer and improves the efficiency of pavement maintenance.

[0059] The method of the present invention is not only highly operational, convenient, and reliable, but also effectively reduces road cracking caused by various reasons. The combined permanent and temporary road construction site saves costs such as demolition and reconstruction, significantly reducing subsequent road maintenance costs. By using the existing road surface as the base layer for the new road, construction time is shortened. Compared to cement concrete pavements, asphalt concrete pavements significantly improve dust suppression and noise reduction, providing greater protection for the surrounding environment.

[0060] Finally, it should be noted that the above-listed embodiments are merely preferred embodiments of the present invention. Of course, those skilled in the art may make changes and modifications to the present invention. If these modifications and variations fall within the scope of the claims of the present invention and their equivalents, they should be considered to be within the scope of protection of the present invention.

Claims

1. A method for preventing cracking of cement concrete pavement by paving asphalt concrete, characterized in that: The following steps are involved: Step 1: Construction of the road base, which is a granular base, and the use of a degradable soil solidifier for base treatment; Step 2: Add measures to prevent uneven settlement of the base layer; specifically, install steel plates or concrete pads with high shear strength at the bottom of the transverse joints of the concrete pavement to prevent uneven settlement of adjacent slabs; Step 3: Cement concrete pavement construction. During the concrete pavement construction process, tie rods and force transmission rods are installed at the expansion joints and contraction joints of the pavement. Steel reinforcement mesh is installed at the false joints where force transmission rods are not installed. Step 4: Cement concrete pavement cutting; Step 5: Fill the cement concrete pavement with light-curing filling material; Step 6: Curb construction; Step 7: Paving the reinforced asphalt concrete pavement. After the asphalt concrete pavement is paved, an adjustable ultraviolet irradiation lamp is used to irradiate the asphalt surface layer; Step 8: Cut the asphalt concrete pavement. The cutting position of the asphalt concrete pavement is consistent with that of the cement concrete pavement. Step 9: Fill the joints of asphalt concrete pavement.

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