A connection structure and construction method of assembled concrete pavement base plate

Abstract

The connection structure of the prefabricated concrete pavement base plate of the present invention is characterized in that it includes a semi-grouting sleeve, a straight thread sleeve, a connecting steel bar and two base plates arranged at intervals, a connecting seam is formed between the two base plates arranged at intervals, the semi-grouting sleeve and the straight thread sleeve are respectively fixed in the two base plates, one end of the connecting steel bar is fixed in the semi-grouting sleeve, and the other end is connected to the straight thread sleeve through a thread; the connecting seam is poured with grouting material. The construction method of the prefabricated concrete pavement soil base plate connection structure is: S1 prefabricated base plate; S2 base plate installation; S3 connection of connecting steel bars; S4 sealing the connecting seam; S5 grouting and pouring concrete; S6 pouring the connecting seam and curing. The connection structure and construction method of the present invention do not need to bend, overlap, or weld the steel bars, the connecting seam is reduced to 5-7 cm, and no vibration operation is required. It has the advantages of high degree of assembly, good durability, low construction noise, and high speed.

Description

Technical Field

[0001] The present invention relates to a connection structure and a construction method for a concrete pavement base plate, and in particular to a connection structure and a construction method for an assembled concrete pavement base plate comprising a semi-grouting sleeve, a straight thread sleeve, a connecting steel bar and two spaced-apart base plate devices. Background Art

[0002] Semi-rigid base is currently a commonly used type of pavement base, but it has large shrinkage, dense surface, easy water accumulation, poor bonding conditions with asphalt surface layer, and easy cracking. The traditional continuous reinforced concrete rigid base is constructed by on-site pouring. Its pouring quality is affected by weather factors such as temperature, wind and rain, and the construction period is long and the construction quality is difficult to control. Using prefabricated assembled continuous reinforced concrete slabs to replace the existing semi-rigid base is one of the ways to solve the above problems.

[0003] The connection structure and process between the prefabricated panels of the prefabricated concrete base are the key technologies that determine the quality of the rigid base. The usual splicing method is the concrete wet joint. Because the welding of steel bars requires a certain overlap length, and the cross-section steel bars are welded and connected by no more than 50%, the specification requires that the overlap section length of the steel bar mechanical connection is 10d (d is the smaller diameter of the connecting steel bar, d is generally greater than 10mm), and the percentage of longitudinal tensile steel bar joints in the same connection section should not be greater than 50%, and the mechanical connection joints of the longitudinal force steel bars should be staggered. This results in the width of the connection seam to be more than 20d (≥20cm). Since the width of the connection seam is more than 20cm, the excessively wide wet joint also means that the amount of high-strength concrete is increased, which increases the cost. At the same time, in the existing wet joint construction, the steel bars need to be bent, overlapped, welded, steel formwork supported, concrete poured, and covered with curing cloth for curing, which is labor-intensive and material-intensive. The interface between the new and old concrete is the weak link of the connection seam. The vibration of the concrete causes noise pollution, the construction period is long, and the degree of assembly is low. Summary of the invention

[0004] In order to overcome the disadvantages of the above technical problems, the present invention provides a connection structure and a construction method for an assembled concrete pavement base plate.

[0005] The connection structure of the prefabricated concrete pavement base plate of the present invention is characterized by: comprising a semi-grouting sleeve, a straight threaded sleeve, connecting steel bars and two base plates arranged at intervals, a connecting seam is formed between the two base plates arranged at intervals, the semi-grouting sleeve and the straight threaded sleeve are respectively fixed in the two base plates on both sides of the connecting seam in a form in which the outer ends are aligned, one end of the connecting steel bar is fixed in the semi-grouting sleeve, and the other end is connected to the straight threaded sleeve through a thread; a polymer-modified cement-based caulking material is poured into the connecting seam.

[0006] According to a specific embodiment of the present invention, vertical grouting pipes and grouting pipes are connected to both ends of the semi-grouting sleeve, the interior of the semi-grouting sleeve is a grouting cavity, and the interiors of the grouting pipe and the grouting pipe are grouting holes and grouting holes communicated with the grouting cavity respectively; one end of the connecting steel bar is inserted into the grouting cavity of the semi-grouting sleeve, and the other end extends out of the grouting cavity, and the grouting cavity is filled with non-shrinkage high-strength grouting material that fixes the connecting steel bar to the semi-grouting sleeve.

[0007] According to another specific embodiment of the present invention, a sealing ring located at the periphery of the connecting steel bar is fixed at the outer port of the grouting chamber, and the outer end of the connecting steel bar is provided with an external threaded portion; the straight thread sleeve is composed of an anchoring portion and an internal threaded portion, the internal threaded portion is located at the outer end, and the external threaded portion of the connecting steel bar is fixedly connected with the internal threaded portion of the straight thread sleeve in a threaded matching manner.

[0008] According to another specific embodiment of the present invention, the base plate is laid on the isolation layer, and lower edge grooves are opened at the lower ends of both sides of the base plate along the road direction, and D-shaped rubber strips with a height greater than the height of the lower edge groove are fixed in the lower edge groove; U-shaped rubber strips with openings aligned with each other are fixed on the side walls of the base plate at both ends of the connecting seam, and PVC high-strength boards are inserted in the two opposite U-shaped rubber strips, and the lower end of the PVC high-strength board is tightly connected to the isolation layer by structural adhesive; the D-shaped rubber strip, the U-shaped rubber strip and the PVC high-strength board make the connecting seam form a closed cavity with only an upper end open.

[0009] According to another specific embodiment of the present invention, half-grouting sleeves and straight thread sleeves are alternately fixed at both ends of the base plate, the half-grouting sleeve at one end is aligned with the straight thread sleeve at the other end, the aligned half-grouting sleeve and straight thread sleeve are connected via the steel bars in the plate, and the connected straight thread sleeves, steel bars in the plate and half-grouting sleeves form an in-plate component.

[0010] According to another specific embodiment of the present invention, the length of the base plate along the road direction is 3.5-4.0m, the length of the base plate along the road width direction is 3.5-7.5m, the thickness of the base plate is 25-30cm, and the width of the connecting seam is 5-7cm; the distance from the center line of the straight thread sleeve and the semi-grouting sleeve to the upper surface of the base plate is 7-9cm; the base plate is interspersed with transverse reinforcement perpendicular to the steel bars in the plate; when the strength grade range of the base plate is 35-40Mpa, the longitudinal reinforcement ratio of the base plate is 0.5%-0.7%.

[0011] According to another specific embodiment of the present invention, the semi-grouting sleeve is made of ductile iron, the length of the semi-grouting sleeve is 250-300 mm, the tensile strength is not less than 550 MPa, and the Brinell hardness HBW is 180-250; the straight thread sleeve is made of No. 45 high-quality carbon structural steel, the annealing tensile strength is not more than 800 MPa, the elongation after fracture is not less than 14%, the length of the straight thread sleeve is 45-60 mm, and the outer diameter is 24-33 mm;

[0012] The connecting steel bars are ribbed steel bars HRB400 with a diameter of 16-22mm. One end is threaded with a length of 30mm-44mm to form an external threaded portion. The tightening force between the connecting steel bars and the straight threaded sleeve is 100-230N·m. The compressive strength of the polymer-modified cement-based caulking material is not less than 60Mpa, the initial fluidity is greater than 200mm, greater than 260mm in 30 minutes, and the compressive strength is greater than 60Mpa after 28 days.

[0013] According to another specific embodiment of the present invention, the height of the lower edge groove is 4 mm and the width is 10 mm; the width of the D-shaped rubber strip is 10 mm and the height is 8 mm, and the D-shaped rubber strip is a porous D-shaped rubber strip; the cross-section of the U-shaped rubber strip is a 6 mm×6 mm square, the groove of the U-shaped rubber strip is 3 mm deep and 4 mm wide; the bottom of the U-shaped rubber strip and its groove are coated with 2 mm thick structural glue, the U-shaped rubber strip is fixed to the end surface of the base plate through the structural glue at the bottom, and the PVC high-strength board is inserted into the groove of the U-shaped rubber strip and fixed by the structural glue.

[0014] According to another specific embodiment of the present invention, the components of the polymer-modified cement-based caulking material include cement, fine sand, high-efficiency expansion agent, polymer, vinyl acetate-ethylene copolymer emulsion, water reducer and defoamer, the cement grade is p||52.5, the fineness modulus of fine sand is 2.8-3.0, the mass proportion of high-efficiency expansion agent is 5-8%, the mass proportion of vinyl acetate-ethylene copolymer emulsion is 8-10%, the mass proportion of water reducer is 2.2-3%, and the mass proportion of defoamer is 0.1-0.3%.

[0015] According to another specific embodiment of the present invention, the structure of the isolation layer below the base plate is a layer of penetrating oil, a 3-5 cm asphalt concrete layer, and two layers of plastic cloth distributed in sequence from bottom to top.

[0016] According to another aspect of the present invention, there is provided a pavement structure formed by a connection structure of a prefabricated concrete pavement base plate, characterized in that the pavement comprises, from bottom to top, a lime soil cushion layer, a cement stabilized crushed stone base layer, an SBS emulsified asphalt penetration layer, an SBS hot asphalt lower sealing layer, an asphalt concrete isolation layer, a prefabricated continuous reinforced cement concrete base layer, an SBS hot asphalt upper sealing layer, a high modulus asphalt concrete lower layer, an SBS emulsified asphalt adhesive layer and an SMA asphalt concrete upper layer, and the prefabricated continuous reinforced cement concrete base layer is composed of base plates spliced ​​together along the road direction.

[0017] According to another aspect of the present invention, a construction method for a connection structure of an assembled concrete pavement base plate is provided, characterized in that it comprises the following specific steps:

[0018] S1 prefabricated base board prefabrication:

[0019] Connect the two ends of the steel bars in the slab to the semi-grouting sleeve and the straight threaded sleeve respectively and fix them on the steel formwork. Pre-embed a rubber strip with a width of 1 cm in the direction of the road, the same length as the base plate in the horizontal direction, and a thickness of 4 mm at the position corresponding to the lower edge groove on the bottom plate of the steel formwork. Apply an isolation agent on the surface of the steel formwork, and pour and cure the base plate concrete.

[0020] S 2 baseboard installation:

[0021] Use a transport flatbed truck and a crane to install the base plate. The distance between the joints is 5-7cm, the height difference between the two base plates is no more than 3mm, and the centering error between the semi-grouting sleeve and the straight thread sleeve is no more than 2mm. Remove the rubber strip at the bottom before placing the base plate and paste a multi-hole D-shaped rubber strip. After the base plate is installed, the D-shaped rubber strip is pressed tightly against the isolation layer under the pressure of the plate weight.

[0022] S3 connection of connecting steel bars:

[0023] Before assembling the base plate, the connecting steel bar is hidden in the semi-grouting sleeve, and the free end is exposed from the semi-grouting sleeve. During assembly, the centering error between the semi-grouting sleeve and the straight thread sleeve shall not exceed 2mm. After assembly, the external thread part of the connecting steel bar is screwed into the internal thread part of the straight thread sleeve to connect the steel bar. The screwing is done manually with a wrench. The torque is 100-230N·m.

[0024] S4 sealed joint seam:

[0025] Glue U-shaped rubber strips on the base plates on both sides of the joint, apply 2mm structural glue in the groove of the U-shaped rubber strip and on the lower isolation layer, and then insert the PVC high-strength plate;

[0026] S5 grouting and pouring concrete:

[0027] Select CGM early-strength non-shrinkage grouting material with a strength grade of no less than 85, inject the grouting material into the semi-grouting sleeve from the grouting hole, and stop grouting when the grouting material overflows from the grouting outlet;

[0028] S6 uses polymer modified cement-based grouting material to fill the joints and cure them after completion.

[0029] The beneficial effects of the present invention are as follows: the connection structure of the prefabricated concrete pavement base plate of the present invention, the semi-grouting sleeve and the straight threaded sleeve located in the two adjacent base plates are connected by connecting steel bars, and there is no need to bend, overlap, or weld the steel bars, thereby improving the overall force-bearing performance of the prefabricated cement concrete plate and enhancing the shear resistance; the width of the connection seam is reduced from the original more than 20 cm to 5-7 cm, and no vibration operation is required when pouring the connection seam of a smaller width, while reducing the amount of high-strength caulking material and reducing the cost. The connection structure of the present invention is used in the construction of highway prefabricated base plates, combining the advantages of the prefabricated construction method of fast speed and low cost, and the semi-cast steel sleeve connection technology of low sealing requirements and easy and quick sleeve fixing. The assembly process is simple and easy to operate, and the base construction time is significantly shortened. It has the advantages of high degree of assembly, little influence by weather, strong integrity, good durability, no vibration, low noise, and high speed.

[0030] Furthermore, by fixing a D-shaped sealing strip in the groove at the lower edge of the base board, the problem of sealing the bottom seam of the base board is solved; by arranging U-shaped rubber strips and PVC high-strength plates on both sides of the connecting seam, sealing of both ends of the connecting seam is achieved, and the connecting seam can be directly poured without the need for erecting a formwork, thereby speeding up the assembly and connection speed of the base board. BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Figure 1 It is a schematic structural diagram of the connection structure of the assembled concrete pavement base plate of the present invention when the connecting steel bar and the straight thread sleeve are not connected;

[0032] Figure 2 for Figure 1 A partial enlarged view of the middle A area;

[0033] Figure 3 It is a schematic diagram of the structure after the connecting steel bar and the straight thread sleeve are connected in the connecting structure of the assembled concrete pavement base plate of the present invention;

[0034] Figure 4 It is a schematic diagram of the structure after the connecting steel bar is connected with the straight thread sleeve and concrete is poured in the connecting structure of the assembled concrete pavement base plate of the present invention;

[0035] Figure 5 It is a schematic diagram of the structure of the base plate in the present invention;

[0036] Figure 6 for Figure 5 Cross-sectional view of the middle BB section;

[0037] Figure 7 It is a schematic diagram of the structure after the base plate of the present invention is placed and connected by connecting steel bars;

[0038] Figure 8 for Figure 7 A partial enlarged view of the middle C area;

[0039] Fig. 9 It is a structural schematic diagram of the reinforcement of the base plate in the present invention;

[0040] Fig.10 It is a schematic diagram of the structure of the components in the board of the present invention;

[0041] Fig.11 It is a schematic diagram of the structure of connecting steel bars in the present invention;

[0042] Fig.12 It is a schematic diagram of the structure of aligning the connecting steel bar and the straight thread sleeve in the present invention;

[0043] Fig.13 It is a schematic diagram of the structure of connecting the steel bar and the straight thread sleeve in the present invention;

[0044] Fig.14 It is a structural schematic diagram of a pavement formed by the connection structure of the assembled concrete pavement base plate of the present invention.

[0045] The reference numerals in the figures are as follows:

[0046] 1 base plate, 2 components in the plate, 3 steel bars in the plate, 4 half grouting sleeve, 5 straight thread sleeve, 6 grouting cavity, 7 connecting steel bars, 8 grouting pipe, 9 grouting pipe, 10 base plate concrete, 11 grouting hole, 12 grouting hole, 13 external thread part, 14 connection joint, 15 non-shrinkage high-strength grouting material, 16 polymer-modified cement-based grouting material, 17 longitudinal reinforcement, 18 transverse reinforcement, 19 internal thread part, 20 anchor part, 21 PVC high-strength plate; 22 lime soil cushion layer, 23 cement stabilized crushed stone subbase, 24 SBS emulsified asphalt permeable layer, 25 SBS hot asphalt lower sealing layer, 26 asphalt concrete isolation layer, 27 assembled continuous reinforced cement concrete base, 28 SBS hot asphalt upper sealing layer, 29 high modulus asphalt concrete lower layer, 30 SBS emulsified asphalt adhesive layer, 31 SMA asphalt concrete upper layer, 32 wrench, 33 sealing ring, 34 D-shaped rubber strip, 35 lower edge groove, 36 U-shaped rubber strip. Implementation

[0047] The following is combined with Figure 1-14 The present invention is further described with reference to the related embodiments.

[0048] like Figure 1 As shown, a schematic diagram of the structure when the connecting steel bar and the straight thread sleeve are not connected in the connection structure of the prefabricated concrete pavement base plate of the present invention is given. The connection structure shown is composed of a semi-grouting sleeve 4, a straight thread sleeve 5 and a connecting steel bar 7. The semi-grouting sleeve 4 and the straight thread sleeve 5 are respectively fixed in two adjacent base plates 1. A connecting seam 14 is formed between the two adjacent base plates 1. One end of the connecting steel bar 7 is located in the semi-grouting sleeve 4, and the other end extends out of the semi-grouting sleeve 4. One end of the connecting steel bar 7 extending out of the semi-grouting sleeve 4 is connected to the straight thread sleeve 5.

[0049] like Figure 2 As shown, given Figure 1 A partial enlarged view of the A area in the middle shows that the lower ends of the base plate 1 on both sides along the road direction are provided with lower edge grooves 35. The lower edge grooves 35 are formed by setting a rubber body at the corresponding position of the lower edge grooves 35 during the prefabrication process of the base plate; when the base plate 1 is laid, the rubber strips used in the prefabrication are replaced with porous D-shaped rubber strips 34 to ensure the sealing of the bottom seam of the base plate. As a specific structural dimension, the height of the lower edge groove 35 is 2-4mm, the width is 8-10mm, and the length is equal to the width of the base plate 1. The width of the porous D-shaped rubber strip 34 is 8-10mm, the height is 7-9mm, and the length is equal to the width of the base plate 1. In this way, since the height of the porous D-shaped rubber strip 34 is greater than the height of the lower edge groove 35, when the base plate 1 is placed on the isolation layer, it is ensured that the bottom seam of the base plate has good sealing. The porous D-shaped rubber strip 34 is preferably the same width as the lower edge groove and 5 mm higher than the height of the lower edge groove 35. In this case, the D-shaped rubber strip 34 is in close contact with the lower edge groove 35 when it shrinks elastically, which can effectively prevent the caulking material at the bottom of the wet joint 14 from overflowing and play a certain protective role on the edges and corners of the template.

[0050] like Figure 3 As shown, a schematic diagram of the structure after the connecting steel bar and the straight threaded sleeve are connected in the connection structure of the assembled concrete pavement base plate of the present invention is given.

[0051] The interior of the semi-grouting sleeve 4 is a grouting cavity 6, and a vertical grouting pipe 8 and a vertical grouting pipe 9 are connected to the semi-grouting sleeve 4. The grouting pipe 8 and the grouting pipe 9 have grouting holes 11 and grouting holes 12, respectively, and the grouting holes 11 and the grouting holes 12 are both connected to the grouting cavity 6. In order to ensure the sealing of the semi-grouting sleeve 4 during the grouting process, a sealing ring 33 is fixed at the end of the grouting cavity 6, and the connecting steel bar 7 passes through the sealing ring 33.

[0052] The outer end of the connecting steel bar 7 is an external threaded portion 13, and the outer end of the inner cavity of the straight thread sleeve 5 is an internal threaded portion 19. For two adjacent base plates 1, the connection is achieved by screwing the external threaded portion 13 of the connecting steel bar 7 in one base plate 1 into the internal threaded portion 19 of the straight thread sleeve 5 in the other base plate 1.

[0053] Two base plates 1 are arranged at intervals along the road direction, and a connection seam 14 is formed between two adjacent base plates 1. The width of the connection seam 14 is 5-7 cm. The connection seam 14 is connected by pouring a polymer-modified cement-based grouting material 16 to achieve the connection between the adjacent base plates 1. The non-shrinkage high-strength grouting material 15 is injected into the semi-grouting sleeve 4 through the grouting hole 11 to achieve a firm connection between the connecting steel bar 7 and the semi-grouting sleeve 4. In this way, the disadvantages of bending, overlapping and welding the steel bars during the splicing of the existing prefabricated structure, which leads to poor quality control and time-consuming and labor-intensive.

[0054] like Figure 4 As shown, a schematic diagram of the structure after the connecting steel bar and the straight threaded sleeve are connected and concrete is poured in the connection structure of the prefabricated concrete pavement base plate of the present invention is given. When a vehicle runs over the connecting seam 14, in order to achieve good bearing of the vehicle load, the width of the connecting seam 14 is as narrow as possible, but since a wrench 32 is required to connect the connecting steel bar 7 and the straight threaded sleeve 5, sufficient operating space needs to be reserved. The common thickness of the base plate is 25-30cm. When the thickness of the base plate is 25cm, the width of the connecting seam 14 should not be less than 5cm; when the thickness of the base plate 1 is 30cm, the width of the connecting seam 14 should not be less than 7cm, otherwise it will affect the construction operation of the wrench 32.

[0055] like Figure 5 As shown, a schematic diagram of the structure of the base plate in the present invention is given. Figure 6 Given Figure 5 In the cross-sectional view of the middle BB section, the two ends of the base plate 1 are alternately fixed with the semi-grouting sleeve 4 and the straight thread sleeve 5, and the semi-grouting sleeve 4 at one end is aligned with the straight thread sleeve 5 at the other end, and the aligned semi-grouting sleeve 4 and the straight thread sleeve 5 are connected via the plate inner steel bar 3. In this way, the connected straight thread sleeve 5, the plate inner steel bar 3 and the semi-grouting sleeve 4 form the plate inner component 2.

[0056] In order to ensure the firmness of the in-slab assembly 2 formed by the straight thread sleeve 5, the in-slab steel bar 3 and the semi-grouting sleeve 4, the semi-grouting sleeve 4 can be made of ductile iron, the length of the semi-grouting sleeve 4 can be 250-300mm, the tensile strength is not less than 550Mpa, and the Brinell hardness HBW is 180-250. The straight thread sleeve 5 can be made of 45# high-quality carbon structural steel, the annealing tensile strength is not more than 800Mpa, the elongation after fracture is not less than 14%, the length of the straight thread sleeve is 45-60mm, and the outer diameter is 24-33mm;

[0057] like Figure 7 As shown, a schematic diagram of the structure of the base plate after being placed and connected by connecting steel bars in the present invention is given. Figure 8 Given Figure 7 The partial enlarged view of the middle C area shows that after the base plate 1 is installed on the isolation layer below, U-shaped rubber strips 36 are fixed on the side walls of the base plate 1 at both ends of the connection seam 14, and the grooves of the two U-shaped rubber strips 36 at the same end of the connection seam 14 are aligned. The PVC high-strength board 21 is inserted into the two opposite U-shaped rubber strips 36, and the lower end of the PVC high-strength board is tightly connected to the isolation layer; because the bottom of the base plate 1 is provided with a porous D-shaped rubber strip 34, the D-shaped rubber strip 34, the U-shaped rubber strip 36 and the PVC high-strength board make the connection seam 14 form a closed cavity with only the upper end open, so that there is no need to erect a template, and the connection seam 14 can be directly poured.

[0058] like Fig. 9 As shown, given Figure 7 The schematic diagram of the reinforcement structure in the connection structure of the prefabricated concrete pavement base plate of the present invention; the unit in the figure is cm. The base plate 1 shown is also provided with transverse reinforcement 18 at intervals along the road direction. The transverse reinforcement 18 is tied together with the connecting steel bar 7, and then the base plate 1 is formed by pouring. The longitudinal reinforcement 17 shown is the in-plate component 2. When the strength rating range of the base plate 1 is 35-40Mpa, the longitudinal reinforcement ratio of the base plate 1 is 0.5%-0.7%.

[0059] like Fig.10 The length of the base plate 1 along the road direction is 3.5-4.0m, the length of the base plate 1 along the road width direction should be adapted to the width of the road it is paved on, usually 3.5-7.5m, and the thickness of the base plate 1 is 25-30cm.

[0060] like Fig.11As shown in the figure, a schematic diagram of the structure of the connecting steel bar in the invention is given. The connecting steel bar 7 can be made of ribbed steel bar HRB400, the diameter of the connecting steel bar 7 is 16-22mm, and one end is processed with a 30mm-44mm long thread to form an external threaded portion 13. The tightening force of the connecting steel bar 7 and the straight threaded sleeve 5 is 100-230N·m. Fig.12 As shown, a schematic diagram of the structure of aligning the connecting steel bar and the straight threaded sleeve in the present invention is given, Fig.13 A schematic diagram of the structure of connecting the connecting steel bar with the straight threaded sleeve by using the handle is given. The compressive strength of the polymer modified cement-based caulking material 16 is not less than 60Mpa, the fluidity is initially greater than 200mm, greater than 260mm in 30 minutes, and the compressive strength is greater than 60Mpa in 28 days.

[0061] Among them, preferably, the components of the polymer-modified cement-based caulking material 16 include cement, fine sand, high-efficiency expansion agent, polymer, vinyl acetate-ethylene copolymer emulsion, water reducer and defoamer, the cement grade is p||52.5, the fineness modulus of fine sand is 2.8-3.0, the mass proportion of high-efficiency expansion agent is 5-8%, the mass proportion of vinyl acetate-ethylene copolymer emulsion is 8-10%, the mass proportion of water reducer is 2.2-3%, and the mass proportion of defoamer is 0.1-0.3%.

[0062] like Fig.14 As shown, a structural schematic diagram of a pavement composed of a connection structure of an assembled concrete pavement base plate of the present invention is given, and the pavement structure shown is, from bottom to top, a lime soil cushion layer 22, a cement stabilized crushed stone base layer 23, an SBS emulsified asphalt penetration layer 24, an SBS hot asphalt lower sealing layer 25, an asphalt concrete isolation layer 26, an assembled continuous reinforced cement concrete base layer 27, an SBS hot asphalt upper sealing layer 28, a high modulus asphalt concrete lower layer 29, an SBS emulsified asphalt adhesive layer 30 and an SMA asphalt concrete upper layer 31.

[0063] According to the construction requirements, the lime soil cushion layer 22, cement stabilized crushed stone subbase 23, SBS emulsified asphalt permeable layer 24, SBS hot asphalt lower sealing layer 25, asphalt concrete isolation layer 26, assembled continuous reinforced cement concrete base 27, SBS hot asphalt upper sealing layer 28, high modulus asphalt concrete lower layer 29, SBS emulsified asphalt adhesive layer 30 and SMA asphalt concrete upper layer 31 are constructed in order from bottom to top;

[0064] Preferably, the isolation layer (ie, the asphalt concrete isolation layer 26 ) below the base plate 1 has a structure of a permeable layer of oil, a 3-5 cm asphalt concrete layer, and two layers of plastic sheets distributed in sequence from bottom to top.

[0065] In addition, the present invention also provides a construction method for a connection structure of an assembled concrete pavement base plate, which is characterized by comprising the following specific steps:

[0066] S1 prefabricated base board prefabrication:

[0067] Connect the two ends of the steel bars in the slab to the semi-grouting sleeve and the straight threaded sleeve respectively and fix them on the steel formwork. Pre-embed a rubber strip with a width of 1 cm in the direction of the road, the same length as the base plate in the horizontal direction, and a thickness of 4 mm at the position corresponding to the lower edge groove on the bottom plate of the steel formwork. Apply an isolation agent on the surface of the steel formwork, and pour and cure the base plate concrete.

[0068] S 2 baseboard installation:

[0069] Use a transport flatbed truck and a crane to install the base plate. The distance between the joints is 5-7cm, the height difference between the two base plates is no more than 3mm, and the centering error between the semi-grouting sleeve and the straight thread sleeve is no more than 2mm. Remove the rubber strip at the bottom before placing the base plate and paste a multi-hole D-shaped rubber strip. After the base plate is installed, the D-shaped rubber strip is pressed tightly against the isolation layer under the pressure of the plate weight.

[0070] S3 connection of connecting steel bars:

[0071] Before assembling the base plate, the connecting steel bar is hidden in the semi-grouting sleeve, and the free end is exposed from the semi-grouting sleeve. During assembly, the centering error between the semi-grouting sleeve and the straight thread sleeve shall not exceed 2mm. After assembly, the external thread part of the connecting steel bar is screwed into the internal thread part of the straight thread sleeve to connect the steel bar. The screwing is done manually with a wrench. The torque is 100-230N·m.

[0072] S4 sealed joint seam:

[0073] Glue U-shaped rubber strips on the base plates on both sides of the joint, apply 2mm structural glue in the groove of the U-shaped rubber strip and on the lower isolation layer, and then insert the PVC high-strength plate;

[0074] S5 grouting and pouring concrete:

[0075] Select CGM early-strength non-shrinkage grouting material with a strength grade of no less than 85, inject the grouting material into the semi-grouting sleeve from the grouting hole, and stop grouting when the grouting material overflows from the grouting outlet;

[0076] S6 uses polymer modified cement-based grouting material to fill the joints and cure them after completion.

[0077] Although the exemplary embodiments and their advantages have been described in detail, it should be understood that various changes, substitutions and modifications may be made to these embodiments without departing from the spirit of the present invention and the scope of protection defined by the appended claims. For other examples, it should be readily understood by those skilled in the art that the order of the process steps may be changed while maintaining the scope of protection of the present invention.

[0078] In addition, the scope of application of the present invention is not limited to the processes, mechanisms, manufactures, material compositions, means, methods and steps of the specific embodiments described in the specification. From the disclosure of the present invention, it will be easily understood by those skilled in the art that the processes, mechanisms, manufactures, material compositions, means, methods or steps that currently exist or will be developed in the future, which perform substantially the same functions as the corresponding embodiments described in the present invention or obtain substantially the same results, can be applied according to the present invention. Therefore, the claims attached to the present invention are intended to include these processes, mechanisms, manufactures, material compositions, means, methods or steps within their scope of protection.

Claims

1. A connection structure of a prefabricated concrete pavement base plate, characterized in that: It comprises a semi-grouting sleeve (4), a straight thread sleeve (5), a connecting steel bar (7) and two spaced-apart base plates (1), a connecting seam (14) being formed between the two spaced-apart base plates, the semi-grouting sleeve and the straight thread sleeve being fixed to the two base plates on both sides of the connecting seam in a manner such that their outer ends are aligned, one end of the connecting steel bar (7) being fixed to the semi-grouting sleeve and the other end being connected to the straight thread sleeve via a thread; a polymer-modified cement-based caulking material (16) is poured into the connecting seam (14); The base plate (1) is laid on the isolation layer, and the lower ends of the base plate on both sides along the road direction are provided with lower edge grooves (35), and D-shaped rubber strips (34) having a height greater than that of the lower edge grooves are fixed in the lower edge grooves; U-shaped rubber strips (36) with openings aligned with each other are fixed on the side walls of the base plate (1) at both ends of the connection seam (14), and PVC high-strength plates (21) are inserted in the two opposite U-shaped rubber strips, and the lower ends of the PVC high-strength plates are tightly connected to the isolation layer by structural adhesive; the D-shaped rubber strips, the U-shaped rubber strips and the PVC high-strength plates make the connection seam (14) form a closed cavity with only an upper end open.

2. The connection structure of the assembled concrete pavement base plate according to claim 1 is characterized in that: The two ends of the semi-grouting sleeve (4) are connected to a vertical grouting pipe (8) and a grouting discharge pipe (9); the interior of the semi-grouting sleeve is a grouting cavity (6); the interiors of the grouting pipe and the grouting discharge pipe are respectively a grouting hole (11) and a grouting discharge hole (12) that are in communication with the grouting cavity; one end of the connecting steel bar (7) is inserted into the grouting cavity of the semi-grouting sleeve, and the other end extends out of the grouting cavity; the grouting cavity is filled with a non-shrinkage high-strength grouting material (15) that fixes the connecting steel bar to the semi-grouting sleeve.

3. The connection structure of the assembled concrete pavement base plate according to claim 2 is characterized in that: A sealing ring (33) is fixed at the outer end of the grouting cavity (6) and is located on the periphery of the connecting steel bar (7). The outer end of the connecting steel bar is provided with an external threaded portion (13). The straight threaded sleeve (5) is composed of an anchoring portion (20) and an internal threaded portion (19). The internal threaded portion is located at the outer end. The external threaded portion of the connecting steel bar is fixedly connected to the internal threaded portion of the straight threaded sleeve in a threaded matching manner.

4. The connection structure of the assembled concrete pavement base plate according to claim 1 or 2, characterized in that: Semi-grouting sleeves (4) and straight thread sleeves (5) are alternately fixed in sequence at both ends of the base plate (1); the semi-grouting sleeve at one end is aligned with the straight thread sleeve at the other end; the aligned semi-grouting sleeves and straight thread sleeves are connected via the plate inner steel bars (3); the connected straight thread sleeves, plate inner steel bars and semi-grouting sleeves form a plate inner assembly (2).

5. The connection structure of the assembled concrete pavement base plate according to claim 4 is characterized in that: The length of the base plate (1) along the road direction is 3.5-4.0 m, the length of the base plate along the road width direction is 3.5-7.5 m, the thickness of the base plate is 25-30 cm, and the width of the connection seam (14) is 5-7 cm; the distance from the center line of the straight thread sleeve and the semi-grouting sleeve to the upper surface of the base plate is 7-9 cm; transverse reinforcement (18) perpendicular to the steel bars (3) in the plate is arranged in the middle of the base plate; when the strength grade of the base plate is in the range of 35-40 MPa, the longitudinal reinforcement ratio of the base plate is 0.5%-0.7%.

6. The connection structure of the assembled concrete pavement base plate according to any one of claims 1 to 3, characterized in that: The semi-grouting sleeve (4) is made of ductile iron, has a length of 250-300 mm, a tensile strength of not less than 550 MPa, and a Brinell hardness HBW of 180-250; the straight thread sleeve (5) is made of No. 45 high-quality carbon structural steel, has an annealed tensile strength of not more than 800 MPa, and an elongation after fracture of not less than 14%, has a length of 45-60 mm, and an outer diameter of 24-33 mm; The connecting steel bar (7) is a ribbed steel bar HRB400, the diameter of the connecting steel bar is 16-22 mm, and one end is threaded with a length of 30 mm-44 mm to form an external threaded portion (13); the tightening force between the connecting steel bar (7) and the straight threaded sleeve (5) is 100-230 N·m; the compressive strength of the polymer modified cement-based caulking material (16) is not less than 60 MPa, the initial fluidity is greater than 200 mm, greater than 260 mm after 30 minutes, and the compressive strength is greater than 60 MPa after 28 days.

7. The connection structure of the assembled concrete pavement base plate according to any one of claims 1 to 3, characterized in that: The height of the lower edge groove (35) is 4 mm and the width is 10 mm; the width of the D-shaped rubber strip is 10 mm and the height is 8 mm, and the D-shaped rubber strip is a porous D-shaped rubber strip; the cross section of the U-shaped rubber strip (36) is a 6 mm×6 mm square, the groove of the U-shaped rubber strip is 3 mm deep and 4 mm wide; a 2 mm thick structural adhesive is applied to the bottom of the U-shaped rubber strip and its groove, and the U-shaped rubber strip is fixed to the end surface of the base plate through the structural adhesive at the bottom, and the PVC high-strength board (21) is inserted into the groove of the U-shaped rubber strip and fixed through the structural adhesive.

8. The connection structure of the assembled concrete pavement base plate according to claim 1 or 2, characterized in that: The components of the polymer modified cement-based caulking material (16) include cement, fine sand, a high-efficiency expansion agent, a polymer, a vinyl acetate-ethylene copolymer emulsion, a water reducer and a defoamer, wherein the cement grade is p||52.5, the fineness modulus of the fine sand is 2.8-3.0, the mass proportion of the high-efficiency expansion agent is 5-8%, the mass proportion of the vinyl acetate-ethylene copolymer emulsion is 8-10%, the mass proportion of the water reducer is 2.2-3%, and the mass proportion of the defoamer is 0.1-0.3%.

9. The connection structure of the assembled concrete pavement base plate according to any one of claims 1 to 3, characterized in that: The structure of the isolation layer below the base plate (1) is a layer of permeable oil, a 3-5 cm asphalt concrete layer, and two layers of plastic cloth, which are distributed in sequence from bottom to top.

10. A pavement structure formed by the connection structure of the assembled concrete pavement base plate according to any one of claims 1 to 3, characterized in that: The road surface comprises, from bottom to top, a lime soil cushion layer (22), a cement stabilized crushed stone subbase layer (23), an SBS emulsified asphalt penetration layer (24), an SBS hot asphalt lower sealing layer (25), an asphalt concrete isolation layer (26), an assembled continuous reinforced cement concrete base layer (27), an SBS hot asphalt upper sealing layer (28), a high modulus asphalt concrete lower layer (29), an SBS emulsified asphalt adhesive layer (30) and an SMA asphalt concrete upper layer (31), wherein the assembled continuous reinforced cement concrete base layer (27) is composed of base plates (1) spliced ​​together along the road direction.

11. A construction method for the connection structure of the assembled concrete pavement base plate according to any one of claims 1 to 3, characterized in that: The specific steps include: S1 prefabricated base board prefabrication: Connect the two ends of the steel bars in the slab to the semi-grouting sleeve and the straight thread sleeve respectively and fix them on the steel formwork. Pre-embed a rubber strip with a width of 1 cm along the road, the same length as the base plate in the horizontal direction, and a thickness of 4 mm at the position corresponding to the groove at the lower edge of the bottom plate of the steel formwork. Apply an isolation agent on the surface of the steel formwork, and pour and cure the base plate concrete. S 2 baseboard installation: Use a transport flatbed truck and a crane to install the base plate. The distance between the joints is 5-7cm, the height difference between the two base plates is no more than 3mm, and the centering error between the semi-grouting sleeve and the straight thread sleeve is no more than 2mm. Remove the rubber strip at the bottom before placing the base plate and paste a multi-hole D-shaped rubber strip. After the base plate is installed, the D-shaped rubber strip is pressed tightly against the isolation layer under the pressure of the plate weight. S3 connection of connecting steel bars: Before assembling the base plate, the connecting steel bar is hidden in the semi-grouting sleeve, and the free end is exposed from the semi-grouting sleeve. During assembly, the centering error between the semi-grouting sleeve and the straight thread sleeve shall not exceed 2mm. After assembly, the external thread part of the connecting steel bar is screwed into the internal thread part of the straight thread sleeve to connect the steel bar. The screwing is done manually with a wrench. The torque is 100-230N·m. S4 sealed joint seam: Glue U-shaped rubber strips on the base plates on both sides of the joint, apply 2mm structural glue in the groove of the U-shaped rubber strip and on the lower isolation layer, and then insert the PVC high-strength board; S5 grouting and pouring concrete: Select CGM early-strength non-shrinkage grouting material with a strength grade of no less than 85, inject the grouting material into the semi-grouting sleeve from the grouting hole, and stop grouting when the grouting material overflows from the grouting outlet; S6 uses polymer modified cement-based grouting material to fill the joints and cure them after completion.

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