CN111877229A - A functional gradient anti-collision guardrail and its construction method - Google Patents

Abstract

The invention discloses a functionally graded anti-collision guardrail which comprises a base, an energy dissipation layer and a UHPC panel, wherein the energy dissipation layer is arranged between the base and the UHPC panel. The invention also provides a construction method of the functional gradient anti-collision guardrail, which comprises the following steps: s1: prefabricating a reinforced concrete base, a UHPC panel and an energy dissipation layer; synchronously reserving pipelines for installing energy dissipation connecting pieces when the reinforced concrete base, the UHPC panel and the energy dissipation layer are prefabricated; s2: mounting the base on a bridge or a road; s3: and installing an energy dissipation layer and an UHPC panel on the base, and inserting an energy dissipation connecting piece to complete the construction of the functional gradient anti-collision guardrail. The crash barrier adopting the functional gradient has the advantages of good guidance, reduction of accident consequences, good durability, low manufacturing cost, short construction period, simple and convenient maintenance and replacement and the like, has great use value and good economic benefit, and has wide application prospect.

Description

A functional gradient anti-collision guardrail and its construction method

technical field

The invention belongs to the field of auxiliary facilities of roads and bridges, and in particular relates to an anti-collision guardrail and a construction method thereof.

Background technique

Highway traffic accidents are closely related to the geometric characteristics of the road and traffic ancillary facilities, and the guardrail on the highway is an important factor affecting traffic safety. Statistics show that in road traffic accidents, 55% of the traffic accidents occur on the highway, and 30% of them are vehicles that contact the highway guardrail (collision, scraping, etc.) or directly drive out of the road. On October 28, 2018, a bus from the Second Yangtze River Bridge in Wanzhou District, Chongqing broke through the bridge guardrail and fell into the Yangtze River, resulting in the death or loss of all 15 people on the bus. On June 13, 2020, a tank truck exploded out of a highway in Wenling City, Zhejiang Province, causing some surrounding houses and factories to collapse, killing 20 people. These accidents have caused extensive thinking and reflection on guardrail design both in engineering and academia.

As an important part of roads and bridge structures, the guardrail's primary role is to avoid or prevent vehicles from driving out of the road and bridge (including vehicles breaking through the guardrail, vehicles overrunning from above the guardrail, vehicles drilling out from under the guardrail, etc.) , so as to ensure the safety of people inside and outside the vehicle, roads, bridges and other buildings. The protection of the guardrail for vehicles and occupants is also reflected in that it should be able to smoothly guide the colliding vehicle to leave the guardrail with a smaller departure angle and a smaller amount of rebound, restore the normal driving trajectory, avoid serious secondary collision accidents, and ensure that the The safety of adjacent roads and other traffic, preventing a serious rollover situation of an out-of-control vehicle. Reinforced concrete guardrails have been widely used in domestic bridge projects due to their advantages of good economy and good impact resistance. However, studies have shown that although the traditional reinforced concrete rigid guardrail has the advantage of strong impact resistance, it has shortcomings such as large impact force for drivers and passengers, and poor vehicle guidance, resulting in a large number of secondary collision accidents, casualties. The steel structure guardrail of the corresponding grade has good energy consumption and better guidance than the rigid concrete guardrail, but it has the disadvantages of high initial cost, easy failure due to steel corrosion problems, high maintenance cost, and the steel guardrail is easy to exist during the collision process. Intrusion into the vehicle body, resulting in the risk of personal injury or death. Therefore, combined with the objective requirements of guardrail functions, it is necessary to further develop a new generation of high-performance guardrails. The requirements of high-performance guardrails are as follows: (1) It can effectively prevent vehicles from rushing out of the guardrail; (2) It has a good buffering and guiding effect to avoid Large amount of rebound and secondary collision accidents.

SUMMARY OF THE INVENTION

The technical problem to be solved by the present invention is to overcome the deficiencies and defects mentioned in the above background art, and to provide a functional gradient anti-collision barrier with good anti-collision performance, good buffering and guiding and a construction method thereof. In order to solve the above-mentioned technical problems, the technical scheme proposed by the present invention is:

A functional gradient crash barrier includes a base, an energy dissipation layer and a UHPC panel, wherein the energy dissipation layer is arranged between the base and the UHPC panel. The above-mentioned functional gradient anti-collision barrier can be set on bridges, on both sides of roads and in the central separation belt.

Preferably, the above-mentioned functional gradient anti-collision guardrail further includes an energy dissipation connector that connects the base, the energy dissipation layer and the UHPC panel into a whole, and the energy dissipation connector is provided with one or more. In addition to connecting the UHPC panel, the base, and the energy dissipation layer, the energy dissipation connector also plays a role in participating in energy dissipation when the UHPC panel is compressed and the energy dissipation layer is displaced when a collision occurs, limiting the displacement of the UHPC panel. ; That is, when the UHPC panel and the energy dissipation layer are compressed along the collision direction after the collision, the deformation of the energy dissipation connector will also be driven to consume energy. As a fragile component, the yield strength of the energy-dissipating connector can be adjusted to meet the requirements of different anti-collision levels, and the installation and replacement of the energy-dissipating connector are very convenient. In the above-mentioned functional gradient anti-collision guardrail, preferably, the energy dissipation connector penetrates the UHPC panel and the energy dissipation layer, and extends into the base, and the installation direction of the energy dissipation connector is different from the impact direction of the vehicle. In parallel, more preferably, the energy dissipating connecting piece is vertically installed on the top of the guardrail, which facilitates its energy dissipating and connecting functions and facilitates installation and replacement. UHPC panels, bases and energy dissipation layers need to reserve pipes for installing energy dissipation connectors. After the assembly is completed, fillers such as polyurethane foam can be filled in the gaps of the pipes to protect the durability of the energy dissipation connectors. effect.

In the above-mentioned functional gradient anti-collision guardrail, preferably, the energy dissipation connector is a metal rod, a metal tube or other components with certain toughness and good ductility (such as a metal composite material rod/tube). Yield strength can meet the needs of different crash performance.

In the present invention, the position and quantity of the energy-dissipating connecting pieces can be adjusted according to the actual construction and assembling requirements of the guardrail, and one or more can be set on the same section. Set on the front side or rear side of the UHPC according to the requirements, and the shape of the energy dissipating connector can also be set to be straight, curved, etc.

In the above functional gradient anti-collision guardrail, preferably, the UHPC panel is pre-configured with transverse reinforcing steel bars or longitudinal reinforcing steel bars. UHPC panels are made of reactive powder concrete or ultra-high performance fiber reinforced concrete. The internal configuration of reinforcing steel bars in two directions is beneficial to improve the strength and impact resistance of UHPC panels.

In the above-mentioned functional gradient anti-collision guardrail, preferably, the energy dissipation layer is a prefabricated component or a cast-in-place component (casting with the base and the UHPC panel as a template), and the energy dissipation layer is polyurethane foam, metal foam, foam concrete Or components with good energy dissipation properties such as metal corrugated plates. The energy dissipation layer should be made of durable energy dissipation materials.

In the above functional gradient anti-collision guardrail, preferably, the energy dissipation layer is assembled and assembled by multiple segments. The energy dissipation layer is assembled by multi-segment, which is convenient for transportation and assembly. The damaged segment can be replaced in time after a collision to ensure the reliability of the structure, and the replacement cost is relatively low.

In the above-mentioned functional gradient anti-collision guardrail, preferably, the base is a prefabricated reinforced concrete base, and a perfusion pipeline for the fixed connection between the base and the bridge or road is reserved in the base. Generally, the connecting steel bars or steel pipe columns of the installation base can be reserved on bridges or roads. When installing the base, connect the filling pipes of the base with the connecting steel bars or steel pipe columns, and then pour UHPC or high-strength mortar into the filling pipes. That's it. The base of the present invention needs to have a reliable connection with bridges and roads, and the structural strength of the base and the strength of the connecting pieces should ensure that the guardrail will not fail as a whole due to the unreliable connecting pieces or the partial failure of the concrete part after the vehicle collides, causing the vehicle to crash. Out of the guardrail, play a role in ensuring safety. In order to improve the strength of the base, transverse steel bars and longitudinal steel bars are generally arranged in the base.

In the above functional gradient anti-collision barrier, preferably, the thickness of the UHPC panel is 5-10 cm, and the thickness of the energy dissipation layer is 8-15 cm. In the present invention, the UHPC panel and the energy dissipation layer are used for the anti-collision guardrail. Through the optimized design and material selection of each energy dissipation layer (for example, UHPC material is selected for the panel to ensure that the thinner components have good anti-collision performance). The energy layers cooperate with each other, and the UHPC panel and the energy dissipation layer in the present invention can meet the requirements by using thinner components, which can greatly reduce the amount of materials used, the thickness of the guardrail, and the transportation and installation cost.

As a general technical concept, the present invention also provides a construction method for the above-mentioned functional gradient crash barrier, comprising the following steps:

S1: Prefabricated reinforced concrete base, UHPC panel and energy dissipation layer; Prefabricated reinforced concrete base, UHPC panel and energy dissipation layer simultaneously reserve pipelines for installing energy dissipation connectors;

S2: Install the base on a bridge or road;

S3: Install the energy dissipation layer and the UHPC panel on the base, and then insert the energy dissipation connector to complete the construction of the functional gradient anti-collision barrier.

Ultra-High Performance Fiber-reinforced Concrete (UHPFRC) is referred to as Ultra High Performance Concrete (UHPC for short), with ultra-high strength (compressive strength>150MPa, tensile strength>8MPa), toughness and The advantages of ultra-high durability (such as chloride ion diffusion coefficient is only 1/100 of ordinary concrete, etc.), etc., are considered to be the most innovative cement-based materials in the past three decades. As a typical UHPC material, reactive powder concrete has been widely used in practical engineering. UHPC not only has ultra-high strength, but also has a unique tensile strain hardening behavior, which makes it have excellent impact resistance and energy dissipation performance. Experiments such as Bindiganavile showed that: under impact, the flexural strength of UHPC is 2 times that of fiber-reinforced concrete, and the fracture energy is as high as 3-4 times. The invention combines ultra-high performance concrete with energy dissipation materials and ordinary concrete structures, and the combination of UHPC panel and energy dissipation layer can play the role of energy dissipation, buffering and guiding, effectively protecting the safety of vehicles and vehicles, and the concrete base is the final safety The bottom line is to protect the vehicle from rushing out of the guardrail. This demand for using different materials to achieve functional gradients has advantages that traditional materials and traditional guardrails cannot achieve. This creative attempt makes full use of the mechanical properties of UHPC, and is expected to It stimulates the huge potential of ultra-high-performance concrete in the field of crash barrier, and has broad industrial application prospects.

In the present invention, the UHPC panel is prefabricated by ultra-high-performance concrete, and together with the energy dissipation layer and the energy dissipation connector of the intermediate interlayer, it forms an energy dissipation component, so as to realize the functions of energy dissipation and guidance after collision, so as to protect the passengers and vehicles. security. The specifications and shapes of UHPC panels, bases and energy dissipation layers can be adjusted according to the actual guardrail grade.

The UHPC panel of the present invention has superior impact resistance, durability and toughness, and the use of prefabricated UHPC panels can not only ensure construction quality, but also ensure the construction efficiency of the entire project. The main function of the contacting components is to transfer the load during collision, disperse the effect of collision, and allow more energy dissipation layers to participate in energy dissipation. performance. The UHPC panel in the present invention utilizes its own energy dissipation characteristics, combined with the energy dissipation layer and the energy dissipation connector closely attached to it, and the combined effect of the three can greatly exert the energy dissipation effect of the structure.

The energy dissipation layer of the invention has the characteristics of light weight, good energy dissipation capacity, corrosion resistance, etc. The energy dissipation layer can be fabricated by prefabrication and then assembled, or it can be constructed by on-site pouring. The combination of the UHPC panel and the energy dissipation layer It can also play a guiding role, which is conducive to the recovery of the vehicle to the driving lane line after a collision, so as to avoid hazards such as the vehicle falling off the bridge and rushing out of the guardrail.

The energy-dissipating connector of the present invention can be simply set as a metal rod or metal tube, or can be set as other structures with good energy-dissipation properties. After the panel is collided, the energy-dissipating layer is compressed along the collision direction, and the energy-dissipating connectors are forced to follow the deformation to participate in energy dissipation, thus playing two roles of connection and energy dissipation. The energy-dissipating connecting piece adopted in the present invention can meet the requirements of guardrails of different anti-collision grades by adjusting the bearing capacity of the energy-dissipating connecting piece, and the installation and construction are very convenient. In the present invention, the energy-dissipating connector can further exert the combined effect of the UHPC panel and the energy-dissipating layer, so as to ensure that the guardrail of the present invention can exert its proper energy-dissipating characteristics.

The base of the present invention is preferably assembled after prefabrication. As a component for ensuring the bearing capacity, the base plays a safety protection function to prevent vehicles from rushing out of the guardrail and causing serious consequences.

In the present invention, the UHPC panel, the energy dissipation layer, the energy dissipation connector and the base have different functions in different parts. After the parts are organically combined, the interaction of the parts can realize the function of functional gradient energy dissipation, which can make the present invention The guardrail in the invention has good buffering and guiding functions, can effectively prevent vehicles from rushing out of the guardrail, avoid large rebound amount and secondary collision accident, and has broad market application prospects.

In the present invention, the UHPC panel, the energy dissipation layer and the energy dissipation connector are all set as components that are easy to replace. Replacing the components after a serious collision can minimize the negative impact caused by the interruption of traffic construction and repairing the structure.

Compared with the prior art, the advantages of the present invention are:

1. The UHPC panel used in the present invention has the advantages of high strength and superior impact resistance. After collision, more areas of the energy dissipation layer can participate in energy dissipation, give full play to the energy dissipation effect of the guardrail, and use its buffering and guiding functions to protect the Safety of occupants and vehicles.

2. The UHPC panel, the base, the energy dissipation layer and other components used in the present invention cooperate with each other and act synergistically, and have the advantages of good anti-collision performance, good buffer guidance and the like.

3. The UHPC panel, base, energy dissipation layer, etc. used in the present invention can all be prefabricated, the construction period is short, the construction efficiency is high, the damaged components can be replaced in time after the accident occurs, the maintenance and replacement are convenient, and the impact of the accident is reduced. .

4. The prefabricated UHPC panels, bases and energy dissipation layers used in the present invention all have good durability, ensure the working performance of bridges and roads in the whole life cycle, and reduce maintenance costs.

5. The anti-collision guardrail used in the present invention is combined with a UHPC panel, a base and an energy dissipating layer. The anti-collision guardrail does not have a steel guardrail structure during a collision. The steel components that may exist pierce into the car and cause casualties to the driver and passengers. phenomenon, can better ensure the safety of drivers and passengers.

In general, the functional gradient anti-collision guardrail of the present invention has the advantages of good guidance, reduced accident consequences, good durability, low cost, short construction period, easy maintenance and replacement, etc., and has great use value and good performance. Economic benefits and broad application prospects.

Description of drawings

In order to illustrate the embodiments of the present invention or the technical solutions in the prior art more clearly, the following briefly introduces the accompanying drawings that need to be used in the description of the embodiments or the prior art. Obviously, the drawings in the following description are For some embodiments of the present invention, for those of ordinary skill in the art, other drawings can also be obtained according to these drawings without creative efforts.

FIG. 1 is a schematic structural diagram of the functional gradient crash barrier in the bridge in Example 1. FIG.

FIG. 2 is a schematic structural diagram of the functionally gradient anti-collision guardrail in the road soil subgrade in Example 2. FIG.

FIG. 3 is a schematic structural diagram of a functionally gradient crash barrier in a separate central divider in Example 3. FIG.

FIG. 4 is a schematic structural diagram of the functional gradient crash barrier in the integral central divider in Example 4. FIG.

illustration:

1. UHPC panel; 2. Base; 3. Energy dissipation layer; 4. Energy dissipation connecting piece; Lifting arm; 10. Reinforcement in the beam; 11. Surface layer; 12. Cushion layer; 13. Steel pipe pile; 14. Dirt roadbed; 15. Corbel; 16. Support block; beam.

Detailed ways

In order to facilitate the understanding of the present invention, the present invention will be described more comprehensively and in detail below with reference to the accompanying drawings and preferred embodiments of the specification, but the protection scope of the present invention is not limited to the following specific embodiments.

Unless otherwise defined, all technical terms used hereinafter have the same meaning as commonly understood by those skilled in the art. The technical terms used herein are only for the purpose of describing specific embodiments, and are not intended to limit the protection scope of the present invention.

Unless otherwise specified, various raw materials, reagents, instruments and equipment used in the present invention can be purchased from the market or can be prepared by existing methods.

Example 1:

As shown in FIG. 1 , the functional gradient crash barrier of this embodiment includes a base 2 , an energy dissipation layer 3 , a UHPC panel 1 and an energy dissipation connector 4 , and the energy dissipation layer 3 is arranged between the base 2 and the UHPC panel 1 . During this time, the base 2 , the energy dissipation layer 3 and the UHPC panel 1 are connected into a whole by the energy dissipation connector 4 , and there are one or more energy dissipation connectors 4 (only one is shown in the figure).

In this embodiment, the guardrail is installed on the beam body pick arm 9, the beam body pick arm 9 reserves the beam body reserved steel bars 6 required for connection with the base 2, and the beam body pick arm 9 is pre-embedded in the beam body steel bar.

In this embodiment, the energy dissipating connector 4 penetrates the UHPC panel 1 and the energy dissipating layer 3 and extends into the base 2 , and the position of the energy dissipating connector 4 is set on the top of the guardrail.

In this embodiment, the energy dissipating connector 4 is a metal rod or a metal tube.

In this embodiment, the UHPC panel 1 is an ultra-high performance concrete structure, and its interior is pre-configured with transverse reinforcing steel bars or longitudinal reinforcing steel bars. The UHPC panel 1 is located on the side of the roadway. As the first contact member in the event of a collision, it first needs sufficient strength and toughness, to ensure that the UHPC panel 1 will not be damaged prematurely, and the functions of energy dissipation and guidance are realized by the joint work of the UHPC panel 1 and the energy dissipation layer 3 and the energy dissipation connector 4 .

In this embodiment, the energy dissipation layer 3 can be prefabricated into small sections for easy transportation, assembled on the base 2 on site, or after the UHPC panel 1 is installed and temporarily fixed, the UHPC panel 1 and the base can be used 2. For the pouring formwork, on-site injection of energy-consuming materials, such as polyurethane foam, foamed concrete, etc.; whether it is prefabricated post-segment assembly or on-site injection of the energy-dissipating layer, after the collision, the damaged energy-dissipating layer can be replaced. 3, Ensure the reliability and effectiveness of the structure.

In this embodiment, the base 2 is a prefabricated reinforced concrete base, and a pouring pipe 5 for the fixed connection between the base 2 and the bridge or road is reserved in the base 2 . The base 2 is prefabricated, and the transverse steel bars 7 and the longitudinal steel bars 8 are arranged in the concrete. When the base 2 is prefabricated, the perfusion pipeline 5 required for assembly shall be reserved. The UHPC is perfused in the perfusion pipeline 5 to ensure the reliability and durability of the connection.

In this embodiment, the thickness of the UHPC panel 1 is 5-10 cm, and the thickness of the energy dissipation layer 3 is 8-15 cm.

The construction method of the above-mentioned functional gradient anti-collision guardrail of the present embodiment includes the following steps:

S1: Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3; Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3 simultaneously reserve pipelines for installing energy dissipation connector 4; prefabricated reinforced concrete base The perfusion pipeline 5 at the connection should be reserved for seat 2;

S2: Install the base 2 on the bridge or road; the perfusion pipeline 5 must correspond to the steel bar 6 reserved for the beam body, and after the installation is completed, the perfusion pipeline 5 is perfused with UHPC;

S3: Install the energy dissipating layer 3 and the UHPC panel 1 on the base 2, then insert the energy dissipating connector 4, and pour polyurethane foam into the space where the energy dissipating connector 4 is installed to complete the construction of the functional gradient crash barrier.

After the construction of the above-mentioned functional gradient anti-collision guardrail is completed, the surface layer 11 or the cushion layer 12 is then paved to complete the construction of the entire bridge deck.

Example 2:

As shown in FIG. 2 , the functional gradient crash barrier of this embodiment includes a base 2 , an energy dissipation layer 3 , a UHPC panel 1 and an energy dissipation connector 4 , and the energy dissipation layer 3 is arranged between the base 2 and the UHPC panel 1 . During this time, the base 2 , the energy dissipation layer 3 and the UHPC panel 1 are connected into a whole by the energy dissipation connector 4 , and there are one or more energy dissipation connectors 4 (only one is shown in the figure).

In this embodiment, the guardrail is installed on the road of the soil roadbed 14 , and the steel pipe pile 13 required for connection with the base 2 is reserved on the soil roadbed 14 .

In this embodiment, the energy dissipating connector 4 penetrates the UHPC panel 1 and the energy dissipating layer 3 and extends into the base 2 , and the position of the energy dissipating connector 4 is set on the top of the guardrail.

In this embodiment, the energy dissipating connector 4 is a metal rod or a metal tube.

In this embodiment, the UHPC panel 1 is an ultra-high performance concrete structure, and its interior is pre-configured with transverse reinforcing steel bars or longitudinal reinforcing steel bars. The UHPC panel 1 is located on the side of the roadway. As the first contact member in the event of a collision, it first needs sufficient strength and toughness, to ensure that the UHPC panel 1 will not be damaged prematurely, and the functions of energy dissipation and guidance are realized by the joint work of the UHPC panel 1 and the energy dissipation layer 3 and the energy dissipation connector 4 .

In this embodiment, the energy dissipation layer 3 can be prefabricated into small sections for easy transportation, assembled on the base 2 on site, or after the UHPC panel 1 is installed and temporarily fixed, the UHPC panel 1 and the base can be used 2. For the pouring formwork, on-site injection of energy-consuming materials, such as polyurethane foam, foamed concrete, etc.; whether it is prefabricated post-segment assembly or on-site injection of the energy-dissipating layer, after the collision, the damaged energy-dissipating layer can be replaced. 3, Ensure the reliability and effectiveness of the structure.

In this embodiment, the base 2 is a prefabricated reinforced concrete base, and a pouring pipe 5 for the fixed connection between the base 2 and the bridge or road is reserved in the base 2 . The base 2 is prefabricated, and the transverse steel bars 7 and the longitudinal steel bars 8 are arranged in the concrete. When the base 2 is prefabricated, it is necessary to reserve the perfusion pipeline 5 required for assembly. 5. High-strength mortar is poured inside to ensure the reliability and durability of the connection.

In this embodiment, the thickness of the UHPC panel 1 is 5-10 cm, and the thickness of the energy dissipation layer 3 is 8-15 cm.

The construction method of the above-mentioned functional gradient anti-collision guardrail of the present embodiment includes the following steps:

S1: Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3; Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3 simultaneously reserve pipelines for installing energy dissipation connector 4; prefabricated reinforced concrete base The perfusion pipeline 5 at the connection should be reserved for seat 2;

S2: Install the base 2 on the soil roadbed 14; the pouring pipeline 5 and the steel pipe pile 13 need to correspond, and after the installation is completed, pour high-strength mortar into the pouring pipeline 5;

S3: Install the energy dissipating layer 3 and the UHPC panel 1 on the base 2, then insert the energy dissipating connector 4, and pour polyurethane foam into the space where the energy dissipating connector 4 is installed to complete the construction of the functional gradient crash barrier.

After the construction of the above-mentioned functional gradient anti-collision guardrail is completed, the surface layer 11 or the cushion layer 12 is then paved to complete the construction of the entire road surface.

Example 3:

As shown in FIG. 3 , the functional gradient crash barrier of this embodiment includes a base 2 , an energy dissipation layer 3 , a UHPC panel 1 and an energy dissipation connector 4 , and the energy dissipation layer 3 is arranged between the base 2 and the UHPC panel 1 . During this time, the base 2 , the energy dissipation layer 3 and the UHPC panel 1 are connected into a whole by the energy dissipation connector 4 , and there are one or more energy dissipation connectors 4 (only one is shown in the figure).

In this embodiment, the guardrail is installed on the split-type central divider.

In this embodiment, the energy dissipating connector 4 penetrates the UHPC panel 1 and the energy dissipating layer 3 and extends into the base 2 , and the position of the energy dissipating connector 4 is set on the top of the guardrail.

In this embodiment, the energy dissipating connector 4 is a metal rod or a metal tube.

In this embodiment, the UHPC panel 1 is an ultra-high performance concrete structure, and its interior is pre-configured with transverse reinforcing steel bars or longitudinal reinforcing steel bars. The UHPC panel 1 is located on the side of the roadway. As the first contact member in the event of a collision, it first needs sufficient strength and toughness, to ensure that the UHPC panel 1 will not be damaged prematurely, and the functions of energy dissipation and guidance are realized by the joint work of the UHPC panel 1 and the energy dissipation layer 3 and the energy dissipation connector 4 .

In this embodiment, the energy dissipation layer 3 can be prefabricated into small sections for easy transportation, assembled on the base 2 on site, or after the UHPC panel 1 is installed and temporarily fixed, the UHPC panel 1 and the base can be used 2. For the pouring formwork, on-site injection of energy-consuming materials, such as polyurethane foam, foamed concrete, etc.; whether it is prefabricated post-segment assembly or on-site injection of the energy-dissipating layer, after the collision, the damaged energy-dissipating layer can be replaced. 3, Ensure the reliability and effectiveness of the structure.

In this embodiment, the base 2 is a prefabricated reinforced concrete base, and the base 2 is prefabricated, and transverse reinforcement bars 7 and longitudinal reinforcement bars 8 are arranged in the concrete.

In this embodiment, the thickness of the UHPC panel 1 is 5-10 cm, and the thickness of the energy dissipation layer 3 is 8-15 cm.

The construction method of the above-mentioned functional gradient anti-collision guardrail of the present embodiment includes the following steps:

S1: Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3; Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3 synchronously reserve the pipeline for installing energy dissipation connector 4;

S2: Install the base 2 on the corbel 15, and install the support block 16 of the central divider;

S3: Install the energy dissipation layer 3 and the UHPC panel 1 on the base 2, then insert the energy dissipation connector 4, and pour polyurethane foam into the space where the energy dissipation connector 4 is installed;

S4: Fill the planting soil 17 between the two guardrails, that is, to complete the construction of the functional gradient anti-collision guardrail.

After the construction of the above-mentioned functional gradient anti-collision guardrail is completed, the surface layer 11 or the cushion layer 12 is then paved to complete the construction of the entire road surface.

Example 4:

As shown in FIG. 4 , the functional gradient anti-collision barrier of this embodiment includes a base 2 , an energy dissipation layer 3 , a UHPC panel 1 and an energy dissipation connector 4 , and the energy dissipation layer 3 is arranged between the base 2 and the UHPC panel 1 . During this time, the base 2 , the energy dissipation layer 3 and the UHPC panel 1 are connected into a whole by the energy dissipation connector 4 , and there are one or more energy dissipation connectors 4 (only one is shown in the figure).

In this embodiment, the guardrail is installed on the split-type central divider.

In this embodiment, the energy dissipating connector 4 penetrates the UHPC panel 1 and the energy dissipating layer 3 and extends into the base 2 , and the position of the energy dissipating connector 4 is set on the top of the guardrail.

In this embodiment, the energy dissipating connector 4 is a metal rod or a metal tube.

In this embodiment, the UHPC panel 1 is an ultra-high performance concrete structure, and its interior is pre-configured with transverse reinforcing steel bars or longitudinal reinforcing steel bars. The UHPC panel 1 is located on the side of the roadway. As the first contact member in the event of a collision, it first needs sufficient strength and toughness, to ensure that the UHPC panel 1 will not be damaged prematurely, and the functions of energy dissipation and guidance are realized by the joint work of the UHPC panel 1 and the energy dissipation layer 3 and the energy dissipation connector 4 .

In this embodiment, the energy dissipation layer 3 can be prefabricated into small sections for easy transportation, assembled on the base 2 on site, or after the UHPC panel 1 is installed and temporarily fixed, the UHPC panel 1 and the base can be used 2. For the pouring formwork, on-site injection of energy-consuming materials, such as polyurethane foam, foamed concrete, etc.; whether it is prefabricated post-segment assembly or on-site injection of the energy-dissipating layer, after the collision, the damaged energy-dissipating layer can be replaced. 3, Ensure the reliability and effectiveness of the structure.

In this embodiment, the base 2 is a prefabricated reinforced concrete base, and the base 2 is prefabricated, and transverse reinforcement bars 7 and longitudinal reinforcement bars 8 are arranged in the concrete.

In this embodiment, the thickness of the UHPC panel 1 is 5-10 cm, and the thickness of the energy dissipation layer 3 is 8-15 cm.

The construction method of the above-mentioned functional gradient anti-collision guardrail of the present embodiment includes the following steps:

S1: Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3; Prefabricated reinforced concrete base 2, UHPC panel 1 and energy dissipation layer 3 synchronously reserve the pipeline for installing energy dissipation connector 4;

S2: Install the base 2 in the channel corbel 18 of the integral central divider;

S3: Install the energy dissipating layer 3 and the UHPC panel 1 on the base 2, then insert the energy dissipating connector 4, and pour polyurethane foam into the space where the energy dissipating connector 4 is installed to complete the construction of the functional gradient crash barrier.

Claims (10)

1. A functionally graded crash barrier, characterized in that it comprises a base (2), an energy dissipation layer (3) and a UHPC panel (1), and the energy dissipation layer (3) is provided on the base (2). ) and the UHPC panel (1). 2. The functional gradient crash barrier according to claim 1, characterized in that it also comprises an energy dissipation connector (4) that connects the base (2), the energy dissipation layer (3) and the UHPC panel (1) into a whole ), the energy dissipation connecting piece (4) is provided with one or more. 3. The functionally graded crash barrier according to claim 2, wherein the energy dissipation connector (4) penetrates through the UHPC panel (1) and the energy dissipation layer (3), and extends to the base In the seat (2), the installation direction of the energy dissipation connecting piece (4) is not parallel to the impact direction of the vehicle. 4. The functional gradient crash barrier according to claim 2, characterized in that, the energy dissipation connector (4) is a metal rod or a metal tube. 5. The functionally graded crash barrier according to any one of claims 1-4, wherein the UHPC panel (1) is pre-configured with transverse reinforcement bars or longitudinal reinforcement bars. 6. The functionally graded crash barrier according to any one of claims 1-4, wherein the energy dissipation layer (3) is a prefabricated component or a cast-in-place component, and the energy dissipation layer (3) is a Polyurethane foam, metal foam, foamed concrete or metal corrugated panels. 7 . The functionally graded crash barrier according to claim 6 , wherein the energy dissipation layer ( 3 ) is assembled and assembled by multiple segments. 8 . 8. The functional gradient crash barrier according to any one of claims 1 to 4, wherein the base (2) is a prefabricated reinforced concrete base, and the base (2) is reserved. There is a perfusion pipeline (5) for the fixed connection between the base (2) and the bridge or road. 9. The functionally gradient crash barrier according to any one of claims 1-4, wherein the thickness of the UHPC panel (1) is 5-10cm, and the thickness of the energy dissipation layer (3) is 8-15cm. 10. A construction method of a functionally gradient crash barrier as claimed in any one of claims 2-9, characterized in that, comprising the following steps: S1: Prefabricated reinforced concrete base (2), UHPC panel (1) and energy dissipation layer (3); prefabricated reinforced concrete base (2), UHPC panel (1) and energy dissipation layer (3) are simultaneously reserved for installation the pipes of the energy dissipating connection (4); S2: Install the base (2) on the bridge or road; S3: Install the energy dissipation layer (3) and the UHPC panel (1) on the base (2), and then insert the energy dissipation connector (4) to complete the construction of the functional gradient crash barrier.

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