Fabricated concrete guardrail design and construction method adopting PBL connecting pieces

Abstract

The invention relates to the technical field of bridge engineering, and discloses a design and construction method of an assembly type concrete guardrail adopting PBL connecting pieces, and the assembly type concrete guardrail adopting the PBL connecting pieces comprises a prefabricated concrete guardrail, a beam body and the PBL connecting pieces; the prefabricated concrete guardrails are installed on the left side and the right side of the beam body and comprise concrete guardrail bodies and connecting bases, and the outer sides of the connecting bases are provided with built-in fixing grooves which are sunken inwards. Flange edges on the left side and the right side of the beam body are provided with concrete convex tooth blocks capable of being matched with the built-in grooves, and a plurality of PBL connecting pieces are pre-buried in the beam body in the direction of the bridge. The prefabricated concrete guardrail, the beam body and the PBL connecting piece are connected through high-strength friction type bolts. According to the fabricated concrete guardrail adopting the PBL connecting piece, the problem of connection reliability of a prefabricated fabricated guardrail and a beam body is solved, the guardrail construction speed can be obviously increased, the construction quality is ensured, it is ensured that the anti-collision performance of the guardrail meets the expected requirement, prefabricated components are convenient to transport and hoist, and the economic benefits of the prefabricated fabricated guardrail are improved.

Description

Technical Field

[0001] The present invention relates to the technical field of bridge engineering, and in particular to a design and construction method of an assembled concrete guardrail using a PBL connector. Background Art

[0002] When building bridges using the traditional on-site casting method, there are many difficulties in terms of construction speed, construction quality, and transportation of construction materials. The construction process is likely to have an impact on the natural environment near the bridge site. In order to solve the problems existing in the traditional on-site casting construction method, the prefabricated and assembled bridge structure system came into being and has gradually been applied in modern bridge engineering.

[0003] However, due to the limitation of hoisting technology, when the length of the hoisting standard section is too long, it is easy to cause the guardrail to crack during the hoisting process, affecting the construction quality. The specification recommends that the length of the standard section of the prefabricated guardrail be 4-6m, which is shorter than the recommended length of the cast-in-place guardrail, making the integrity of the prefabricated guardrail poor, and there are natural disadvantages in anti-overturning and anti-collision capabilities.

[0004] The development of prefabricated guardrails will inevitably put forward higher requirements for the design and construction of guardrails. Prefabricated guardrails need to be connected to bridges in various forms. The reliability of the connector determines the reliability of the prefabricated anti-collision guardrail. Precise and complex calculations are required during the design process to ensure the safety of the prefabricated guardrail. At the same time, since the various components of the prefabricated guardrail need to be accurately installed on site, it is necessary to ensure that the layout of each embedded part is accurate. Once there is a deviation during the installation process, it will affect the anti-collision performance and appearance quality of the anti-collision guardrail. Therefore, it also increases the quality requirements for construction personnel and the accuracy and stability requirements for construction equipment.

[0005] In general, when hoisting and installing the prefabricated concrete anti-collision guardrail, the standard section of the guardrail must be connected to the bridge structure as a whole with appropriate and reliable connectors and connection methods (vertical connection), that is, the guardrail system has a certain degree of anti-overturning ability through the connection with the bridge deck; at the same time, it is also necessary to set up a longitudinal connection to connect the front and rear standard sections of the guardrail into a whole to enhance the integrity and stability of the guardrail. The superior vertical connection can meet the convenience requirements of the development of prefabrication while meeting the actual use function of the structure. That is, when a collision occurs, the connector has sufficient strength to withstand the damage to the guardrail structure caused by the impact load, and can also be installed quickly. Guardrails of different lengths and different protection levels have different requirements for the required connection form. The appropriate connection can not only meet the safety requirements but also the principle of economy and applicability. Summary of the invention

[0006] In order to solve the problem of vertical connection between the prefabricated assembled anti-collision guardrail and the bridge body proposed in the background technology, the present invention proposes a design and construction method of an assembled concrete guardrail using PBL connectors. The assembled concrete guardrail using PBL connectors can ensure connection strength and stability, and the construction is convenient and the installation efficiency is high.

[0007] The technical solution adopted by the present invention is:

[0008] An assembled concrete guardrail using a PBL connector, the assembled concrete guardrail using the PBL connector comprising a precast concrete guardrail, a beam body and a PBL connector;

[0009] The precast concrete guardrail is installed on the left and right sides of the beam body, and includes a concrete guardrail body at the upper part and a connecting seat at the lower part connected to the beam body; the outer side of the connecting seat is provided with an inwardly recessed embedding groove;

[0010] The flange edges on both sides of the beam body are provided with concrete protruding teeth blocks protruding upwards and capable of cooperating with the embedding grooves, and the beam body is pre-embedded with a plurality of PBL connectors along the direction of the bridge at the inner edge of the connecting seat;

[0011] The precast concrete guardrail, the beam body and the PBL connector are connected by high-strength friction bolts that pass through the block, the connecting seat and the PBL connector in sequence, so that several precast concrete guardrails are installed on the left and right sides of the beam body along the direction of the bridge.

[0012] Furthermore, the upper concrete guardrail body and the lower connecting seat of the precast concrete guardrail are reinforced concrete structures in which steel bars cooperate with formwork for concrete pouring. Bolt connection holes need to be reserved before pouring concrete. Before pouring concrete, several guardrail embedded steel plates are embedded on the connection side of the connecting seat and the PBL connector.

[0013] Furthermore, the embedded steel plate of the guardrail is welded to the steel bars in the precast concrete guardrail.

[0014] Furthermore, the concrete convex tooth block is a reinforced concrete structure in which concrete is poured by means of steel bars and formwork.

[0015] Further, the PBL connector includes a PBL connector embedded steel plate, a PBL connector perforated plate, a PBL connector embedded steel bar, and a PBL connector connecting steel plate;

[0016] The bottom of the PBL connector embedded steel plate is welded to the PBL connector perforated plate, the PBL connector embedded steel bar passes through the PBL connector perforated plate through the through hole on the PBL connector perforated plate, the PBL connector embedded steel plate, the PBL connector perforated plate and the PBL connector embedded steel bar are all located in the beam body, and the top surface of the PBL connector embedded steel plate and the upper surface of the beam body are located in the same horizontal plane;

[0017] The upper part of the PBL connector embedded steel plate is welded to the PBL connector connecting steel plate, and the PBL connector connecting steel plate is provided with a through hole for the high-strength friction bolt to pass through.

[0018] Further, the perforated plate of the PBL connector is arranged along the left-right direction of the beam body, and the embedded steel bars of the PBL connector are arranged along the direction of the bridge; or the perforated plate of the PBL connector is arranged along the direction of the bridge, and the embedded steel bars of the PBL connector are arranged along the left-right direction of the beam body.

[0019] A method for designing an assembled concrete guardrail, the method for designing an assembled concrete guardrail is directed to the assembled concrete guardrail using the PBL connector, and comprises the following steps:

[0020] Step 1: Determine the guardrail grade and design load according to the anti-collision grade requirements;

[0021] Step 2: Design PBL connectors and high-strength friction bolt connectors; calculate the load design values ​​of PBL connectors and high-strength friction bolts according to the design load, design the PBL shear key structure according to the corresponding specifications, and determine the size and model of the high-strength friction bolts;

[0022] Step three, design the reinforcement of the concrete convex tooth block;

[0023] Step 4: Supplement the construction requirements for the prefabricated guardrail according to the specifications, including: the hole diameter, spacing, and margin distance of the high-strength friction bolt openings, the grade and preload of the high-strength friction bolts, the anti-slip coefficient of the friction surface of the high-strength friction bolt connection, and the hole size requirements of the PBL connector plate.

[0024] Further, in step 2, the design of the PBL connector and the high-strength friction bolt connector includes the following steps:

[0025] First, determine the design value N of the connector load according to the height of the assembled guardrail;

[0026] Secondly, the shear bearing capacity of the PBL connector is verified by the following formula:

[0027]

[0028]

[0029] Where n is the number of PBL connectors per linear meter; is the design value of the single-hole shear bearing capacity of the PBL connector; d1 is the opening diameter; d2 is the diameter of the transverse through-steel bar; f td is the design value of concrete axial tensile strength; f vd is the design value of the steel bar shear strength; f sd is the design value of steel bar tensile strength; α is the improvement coefficient;

[0030] Finally, the high-strength friction bolt connection is verified by the following formula:

[0031]

[0032]

[0033] Where m is the number of high-strength friction bolt connections per linear meter; is the design value of the shear bearing capacity of a high-strength friction bolt connection; P d is the pre-tension of a high-strength friction bolt connection; n f is the number of force transmission friction surfaces; μ is the anti-slip coefficient of the friction surface.

[0034] Further, in step three, the strength calculation of the concrete convex tooth block includes the following steps:

[0035] Assume that the guardrail has a load of F per linear meter. t The concrete convex tooth block bears all the load, and the concrete convex tooth block strength is verified by the following formula:

[0036] F s =f sd S>F t

[0037] In the formula, F s f is the shear bearing capacity of the concrete convex tooth block; sd is the design value of tensile strength of ordinary steel bars; S is the cross-sectional area of ​​shear steel bars per linear meter.

[0038] A construction method for an assembled concrete guardrail, the construction method for an assembled concrete guardrail is directed to the above-mentioned assembled concrete guardrail using a PBL connector, and comprises the following steps:

[0039] Step S1, respectively tying the steel bars of the prefabricated guardrail, the beam body, and the concrete convex tooth block; and pre-embedding the steel plate at the corresponding position of the prefabricated guardrail, and pre-embedding the PBL connector at the corresponding position of the beam body; and reserving bolt holes at the corresponding positions of the prefabricated guardrail, the PBL connector, and the concrete convex tooth block when pouring concrete;

[0040] Step S2, after the concrete of the prefabricated concrete guardrail and the beam body using the PBL connector is cured, the guardrail is assembled to ensure that the reserved bolt holes are aligned; high-strength friction bolts are assembled to complete the connection between the prefabricated concrete guardrail and the beam body, thereby completing the connection between the prefabricated concrete guardrail and the beam body using the PBL connector.

[0041] The beneficial effects of the present invention are:

[0042] The present invention proposes an assembled concrete guardrail using a PBL connector, which solves the problem of reliability in connection between the prefabricated assembled guardrail and the beam body, can significantly speed up the construction of the guardrail, ensure the construction quality, ensure that the anti-collision performance of the guardrail meets the expected requirements, and facilitates the transportation and hoisting of prefabricated components, which is conducive to improving the economic benefits of the prefabricated assembled guardrail. BRIEF DESCRIPTION OF THE DRAWINGS

[0043] In order to more clearly illustrate the embodiments of the present application or the technical solutions in the prior art, the drawings required for use in the embodiments will be briefly introduced below. Obviously, the drawings described below are only some embodiments recorded in the present invention. For ordinary technicians in this field, other drawings can also be obtained based on these drawings.

[0044] Figure 1 It is a front view of the assembled concrete guardrail using the PBL connector of the present invention;

[0045] Figure 2 A side view of an assembled concrete guardrail using a PBL connector according to the present invention;

[0046] Figure 3 It is an enlarged schematic diagram of the concrete convex tooth block and the guardrail embedding groove of the present invention;

[0047] Figure 4 It is a side view of the precast concrete guardrail of the present invention;

[0048] Figure 5 is a cross-sectional view of the precast concrete guardrail of the present invention;

[0049] Figure 6 It is an enlarged schematic diagram of the connection between the precast concrete guardrail and the pre-embedded PBL connector of the beam body of the present invention;

[0050] Figure 7 and Figure 8 Another layout diagram of the PBL connector of the assembled concrete guardrail using the PBL connector of the present invention;

[0051] In the figure, 1 is a precast concrete guardrail, 2 is a beam, 3 is a PBL connector, 301 is a PBL connector embedded steel plate, 32 is a PBL connector perforated plate, 33 is a PBL connector embedded steel bar, 34 is a PBL connector connecting steel plate, 4 is a high-strength friction bolt connector, 41 is a high-strength friction bolt, 42 is a nut, 5 is an embedding groove, 6 is a bolt connection hole, 7 is a guardrail embedded steel plate, 8 is a steel bar, and 9 is a concrete convex tooth block. DETAILED DESCRIPTION

[0052] The following will be combined with the drawings of the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the described embodiments are only part of the embodiments of the present invention, not all of the embodiments. All other embodiments obtained by ordinary technicians in this field based on the embodiments of the present invention without creative work are within the scope of protection of the present invention.

[0053] Example 1

[0054] In view of the problems existing in the vertical connection between the prefabricated anti-collision guardrail and the bridge body, this embodiment provides an assembled concrete guardrail using a PBL connector. Figure 1 As shown, the assembled concrete guardrail using the PBL connector includes three parts: a precast concrete guardrail 1, a beam body 2 and a PBL connector 3.

[0055] Among them, Figure 2 As shown, the precast concrete guardrail 1 is installed on the left and right sides of the beam body 2. The precast concrete guardrail 1 includes a concrete guardrail body at the upper part and a connecting seat at the lower part connected to the beam body 2. The outer side of the connecting seat of the precast concrete guardrail 1 is provided with an inwardly recessed embedding groove 5. Figure 2 As shown, the flange edges on both sides of the beam body 2 are provided with upwardly protruding concrete tooth blocks 9, which can cooperate with the embedded groove 5 to limit the precast concrete guardrail 1 on one side. Figure 1 and Figure 2 As shown, a plurality of PBL connectors 3 are pre-embedded at the inner edge of the connecting seat of the beam body 2 along the direction of the bridge.

[0056] like Figure 2 and Figure 3As shown, the precast concrete guardrail 1, the beam 2 and the PBL connector 3 are connected by high-strength friction bolts that pass through the block, the connection seat of the precast concrete guardrail 1 and the PBL connector 3 in sequence, so that a plurality of precast concrete guardrails 1 are installed on the left and right sides of the beam 2 along the direction of the bridge. The assembled concrete guardrail structure using the PBL connector significantly improves the connection reliability of the guardrail by using the PBL connector 3, and reduces the safety hazards caused by improper connection; the assembled structure is easy to transport and hoist, and can speed up the construction speed while ensuring the quality; therefore, it helps to improve the economic benefits of the precast assembled guardrail.

[0057] Furthermore, the various structures constituting the assembled concrete guardrail using the PBL connector are described in detail as follows:

[0058] Precast concrete guardrail 1: Figure 2 , Figure 4 ,and Figure 5 As shown, the upper concrete guardrail body and the lower connection seat of the precast concrete guardrail 1 are reinforced concrete structures for concrete pouring with steel bars and templates, and bolt connection holes 6 need to be reserved before pouring concrete. Before pouring concrete, a number of guardrail embedded steel plates 7 are embedded on the connection side of the connection seat and the PBL connector 3, and the guardrail embedded steel plates 7 are welded and connected to the steel bars 8 in the precast concrete guardrail 1; the guardrail embedded steel plates 7 enhance the stability and bearing capacity of the overall structure; at the same time, when configuring the steel bars and templates, an inwardly recessed embedding groove 5 is reserved according to the design size.

[0059] Beam 2: Beam 2 is a reinforced concrete structure that is poured with concrete by using steel bars and formwork; PBL connectors 3 need to be embedded before pouring concrete for beam 2, and PBL connectors 3 are embedded along the direction of the bridge. The concrete protruding teeth 9 protruding upwards at the flange edges on both sides of beam 2 are also reinforced concrete structures that are poured with concrete by using steel bars and formwork.

[0060] PBL connector 3: Figure 1 , Figure 2 , Figure 6 As shown, the PBL connector 3 includes a PBL connector embedded steel plate 31, a PBL connector perforated plate 32, a PBL connector embedded steel bar 33, and a PBL connector connecting steel plate 34. Among them, the bottom of the PBL connector embedded steel plate 31 is welded to the PBL connector perforated plate 32, the PBL connector embedded steel bar 33 passes through the PBL connector perforated plate 32 through the through hole on the PBL connector perforated plate 32, the PBL connector embedded steel plate 31, the PBL connector perforated plate 32 and the PBL connector embedded steel bar 33 are all located in the beam body 2, and the top surface of the PBL connector embedded steel plate 31 is located at the same horizontal plane as the upper surface of the beam body 2.

[0061] In addition, the upper part of the PBL connector embedded steel plate 31 is welded to the PBL connector connecting steel plate 34, and the PBL connector connecting steel plate 34 can fit with the guardrail embedded steel plate 7 on one side of the connecting seat of the precast concrete guardrail 1, and the PBL connector connecting steel plate 34 is provided with a through hole for high-strength friction bolts to pass through.

[0062] High-strength friction bolt connector 4: Figure 2 As shown, the high-strength friction bolt connector 4 needs to pass through the concrete convex tooth block 9, the precast concrete guardrail 1, the guardrail embedded steel plate 7, and the PBL connector connecting steel plate 34. After the precast concrete guardrail 1 is assembled in place, the high-strength friction bolt connector 4 is installed. Figure 3 As shown, the high-strength friction bolt connector 4 includes a high-strength friction screw 41 and a nut 42 .

[0063] It should be noted that, in this embodiment, the PBL connector 3 embedded in the beam body 2, the PBL connector opening plate 32 and the PBL connector embedded steel bar 33 can be arranged in a variety of ways according to the actual construction requirements on site; Arrangement method 1: Figure 1 , Figure 2 and Figure 6 As shown, the PBL connector perforated plate 32 is arranged along the left and right direction of the beam body 2, and the PBL connector embedded steel bars 33 are arranged along the direction of the bridge. Arrangement method 2: Figure 7 and Figure 8 As shown, according to the actual construction requirements on site, the PBL connector perforated plate 32 is arranged along the direction of the bridge, and the PBL connector embedded steel bars 33 are arranged along the left and right directions of the beam body 2.

[0064] Example 2

[0065] Based on the assembled concrete guardrail using the PBL connector provided in Example 1, this embodiment proposes an assembled concrete guardrail design method for the assembled concrete guardrail using the PBL connector, which specifically includes the following steps:

[0066] Step 1: Determine the guardrail grade and design load according to the anti-collision grade requirements;

[0067] Step 2: Design the PBL connector 3 and the high-strength friction bolt connector 4. Calculate the load design value of the PBL connector 3 and the high-strength friction bolt according to the design load, design the PBL shear key structure and determine the size and model of the high-strength friction bolt according to the corresponding specifications. The design of the PBL connector 3 and the high-strength friction bolt connector 4 includes the following steps:

[0068] Determine the design value N of the connector load based on the height of the prefabricated guardrail.

[0069] The shear bearing capacity of PBL connector 3 is verified by the following formula:

[0070]

[0071]

[0072] In the formula, n is the number of PBL connectors per linear meter; is the design value of the single-hole shear bearing capacity of the PBL connector 3; d1 is the opening diameter; d2 is the diameter of the transverse through-steel bar, i.e. the diameter of the embedded steel bar of the PBL connector; f td is the design value of concrete axial tensile strength; f vd is the design value of the shear strength of the steel bar, according to the formula f vd =0.577f sd Calculate, f sd is the design value of the tensile strength of the steel bar; α is the improvement coefficient, which is taken as 6.1.

[0073] The high-strength friction bolt connection 4 is verified by the following formula:

[0074]

[0075]

[0076] Where m is the number of high-strength friction bolt connections per linear meter; is the design value of the shear bearing capacity of a high-strength friction bolt connection; P d is the pre-tension of a high-strength friction bolt connection; n f is the number of force transmission friction surfaces; μ is the anti-slip coefficient of the friction surface.

[0077] Step 3: Design the reinforcement of the concrete convex tooth block 9. The strength calculation of the concrete convex tooth block 9 includes the following steps:

[0078] Assume that the guardrail has a load of F per linear meter. t The concrete convex tooth block 9 bears all the load, and the strength of the concrete convex tooth block 9 is verified by the following formula:

[0079] F s =f sd S>F t

[0080] In the formula, F s f is the shear bearing capacity of the concrete convex tooth block 9; sd is the design value of tensile strength of ordinary steel bars; S is the cross-sectional area of ​​shear steel bars per linear meter.

[0081] Step 4: Supplement the construction requirements for the prefabricated guardrail according to the specifications, including: the hole diameter, spacing, and margin of the high-strength friction bolt openings, the grade and preload of the high-strength friction bolts, the anti-slip coefficient of the friction surface of the high-strength friction bolt connection, and the hole size requirements of the PBL connector 3 plates.

[0082] Through the above design steps, it is ensured that the prefabricated concrete guardrail based on the PBL connector 3 meets the design requirements in terms of bearing capacity and stability, and is suitable for the construction needs of guardrails with different anti-collision levels.

[0083] Example 3

[0084] Based on the assembled concrete guardrail using the PBL connector provided in Example 1, this embodiment provides a construction method for the assembled concrete guardrail using the PBL connector, which specifically includes the following steps:

[0085] Step S1, respectively tying the steel bars of the prefabricated guardrail, the beam body 2, and the concrete convex tooth block 9; and pre-embedding the steel plate at the corresponding position of the prefabricated guardrail, and pre-embedding the PBL connector 3 at the corresponding position of the beam body 2; and reserving bolt holes at the corresponding positions of the prefabricated guardrail, the PBL connector 3, and the concrete convex tooth block 9 when pouring concrete;

[0086] Step S2, after the concrete curing of the assembled concrete guardrail and beam body 2 using the PBL connector is completed, the guardrail is assembled to ensure that the reserved bolt holes are aligned; high-strength friction bolts are assembled to complete the connection between the assembled concrete guardrail and the beam body 2, thereby completing the connection work of the assembled concrete guardrail using the PBL connector.

[0087] In summary, the assembled concrete guardrail using PBL connectors solves the problem of reliability of connection between the prefabricated assembled guardrail and the beam body 2, can significantly speed up the construction of the guardrail, ensure the construction quality, ensure that the anti-collision performance of the guardrail meets the expected requirements, and facilitates the transportation and hoisting of prefabricated components, which is conducive to improving the economic benefits of the prefabricated assembled guardrail.

[0088] The above shows and describes the basic principles, main features and advantages of the present invention. It should be understood by those skilled in the art that the present invention is not limited to the above embodiments, and the above embodiments and descriptions are only for explaining the principles of the present invention. Without departing from the spirit and scope of the present invention, the present invention may have various changes and improvements, which fall within the scope of the present invention to be protected. The scope of protection of the present invention is defined by the attached claims and their equivalents.

Claims

1. An assembled concrete guardrail using a PBL connector, characterized in that: The assembled concrete guardrail using the PBL connector includes a precast concrete guardrail, a beam body and a PBL connector; The precast concrete guardrail is installed on the left and right sides of the beam body, and includes a concrete guardrail body at the upper part and a connecting seat at the lower part connected to the beam body; the outer side of the connecting seat is provided with an inwardly recessed embedding groove; The flange edges on both sides of the beam body are provided with concrete protruding teeth blocks protruding upwards and capable of cooperating with the embedding grooves, and the beam body is pre-embedded with a plurality of PBL connectors along the direction of the bridge at the inner edge position of the connecting seat; The precast concrete guardrail, the beam body and the PBL connector are connected by high-strength friction bolts that pass through the block, the connecting seat and the PBL connector in sequence, so that several precast concrete guardrails are installed on the left and right sides of the beam body along the direction of the bridge.

2. The assembled concrete guardrail using the PBL connector according to claim 1 is characterized in that: The upper concrete guardrail body and the lower connecting seat of the precast concrete guardrail are reinforced concrete structures in which steel bars cooperate with formwork for concrete pouring. Bolt connection holes need to be reserved before pouring concrete. Before pouring concrete, several guardrail embedded steel plates are embedded on the connecting side of the connecting seat and the PBL connector.

3. The assembled concrete guardrail using PBL connectors according to claim 2 is characterized in that: The guardrail embedded steel plate is welded to the steel bars in the precast concrete guardrail.

4. The assembled concrete guardrail using PBL connectors according to claim 1 is characterized in that: The concrete convex tooth block is a reinforced concrete structure in which concrete is poured by means of steel bars and a template.

5. The assembled concrete guardrail using PBL connectors according to claim 1 is characterized in that: The PBL connector includes a PBL connector embedded steel plate, a PBL connector perforated plate, a PBL connector embedded steel bar, and a PBL connector connecting steel plate; The bottom of the PBL connector embedded steel plate is welded to the PBL connector perforated plate, the PBL connector embedded steel bar passes through the PBL connector perforated plate through the through hole on the PBL connector perforated plate, the PBL connector embedded steel plate, the PBL connector perforated plate and the PBL connector embedded steel bar are all located in the beam body, and the top surface of the PBL connector embedded steel plate and the upper surface of the beam body are located in the same horizontal plane; The upper part of the PBL connector embedded steel plate is welded to the PBL connector connecting steel plate, and the PBL connector connecting steel plate is provided with a through hole for the high-strength friction bolt to pass through.

6. The assembled concrete guardrail using PBL connectors according to claim 5 is characterized in that: The perforated plate of the PBL connector is arranged along the left-right direction of the beam body, and the embedded steel bars of the PBL connector are arranged along the direction of the bridge; or the perforated plate of the PBL connector is arranged along the direction of the bridge, and the embedded steel bars of the PBL connector are arranged along the left-right direction of the beam body.

7. A method for designing an assembled concrete guardrail, the method for designing an assembled concrete guardrail being directed to the assembled concrete guardrail using a PBL connector as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: Step 1: Determine the guardrail grade and design load according to the anti-collision grade requirements; Step 2: Design PBL connectors and high-strength friction bolt connectors; calculate the load design values ​​of PBL connectors and high-strength friction bolts according to the design load, design the PBL shear key structure according to the corresponding specifications, and determine the size and model of the high-strength friction bolts; Step three, design the reinforcement of the concrete convex tooth block; Step 4: Supplement the construction requirements for the prefabricated guardrail according to the specifications, including: the hole diameter, spacing, and margin distance of the high-strength friction bolt openings, the grade and preload of the high-strength friction bolts, the anti-slip coefficient of the friction surface of the high-strength friction bolt connection, and the hole size requirements of the PBL connector plate.

8. The method for designing a prefabricated concrete guardrail according to claim 7 is characterized in that: In step 2, the PBL connector design and high-strength friction bolt connector design are The following steps are involved: First, determine the design value N of the connector load according to the height of the assembled guardrail; Secondly, the shear bearing capacity of the PBL connector is verified by the following formula: Where n is the number of PBL connectors per linear meter; is the design value of the single-hole shear bearing capacity of the PBL connector; d1 is the opening diameter; d2 is the diameter of the transverse through-steel bar; f td is the design value of concrete axial tensile strength; f vd is the design value of the steel bar shear strength; f sd is the design value of steel bar tensile strength; α is the improvement coefficient; Finally, the high-strength friction bolt connection is verified by the following formula: Where m is the number of high-strength friction bolt connections per linear meter; is the design value of the shear bearing capacity of a high-strength friction bolt connection; P d is the pretension of a high-strength friction bolt connection; n f is the number of force transmission friction surfaces; μ is the anti-slip coefficient of the friction surface.

9. The method for designing an assembled concrete guardrail according to claim 7, characterized in that: In step three, the strength verification of the concrete convex tooth block includes the following steps: Assume that the guardrail has a load of F per linear meter. t The concrete convex tooth block bears all the load, and the concrete convex tooth block strength is verified by the following formula: F s =f sd S>F t In the formula, F s f is the shear bearing capacity of the concrete convex tooth block; sd is the design value of tensile strength of ordinary steel bars; S is the cross-sectional area of ​​shear steel bars per linear meter.

10. A method for constructing an assembled concrete guardrail, the method for constructing an assembled concrete guardrail being directed to the assembled concrete guardrail using a PBL connector as claimed in any one of claims 1 to 6, characterized in that: The following steps are involved: Step S1, respectively tying the steel bars of the assembled prefabricated guardrail, the beam body, and the concrete convex tooth block; Steel plates are embedded in the corresponding positions of the prefabricated guardrails, and PBL connectors are embedded in the corresponding positions of the beams; bolt holes are reserved in the corresponding positions of the prefabricated guardrails, PBL connectors, and concrete convex tooth blocks when pouring concrete; Step S2, after the concrete of the prefabricated concrete guardrail and the beam body using the PBL connector is cured, the guardrail is assembled to ensure that the reserved bolt holes are aligned; high-strength friction bolts are assembled to complete the connection between the prefabricated concrete guardrail and the beam body, thereby completing the connection between the prefabricated concrete guardrail and the beam body using the PBL connector.

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