CN104047245A - Guard bar and mounting method thereof - Google Patents

Abstract

The invention discloses a guardrail, which includes a guardrail column and a steel wire rope. The guardrail column includes: an arc plate that can be connected with the steel wire rope. The central angle of the arc plate is less than 180°. It can be seen from the above-mentioned technical scheme that the guardrail provided by the present invention includes a guardrail column and a steel wire rope connected with the guardrail column. The guardrail column provided by this program adjusts the longitudinal and lateral stiffness ratios of the guardrail column by changing the cross-sectional shape of the guardrail column, and the moment of inertia The corresponding increase also increases the contact area when the accident vehicle collides with the guardrail. During the collision process between the accident vehicle and the guardrail column, the collision force is decomposed into two directions along the road tangent direction and perpendicular to the road tangent direction, which improves the absorption capacity. The effect of balanced distribution of energy density and the synergistic force bearing capacity between the guardrail column and the wire rope improve the safety performance of the guardrail to a certain extent. The invention also provides a guardrail installation method.

Description

A guardrail and its installation method

technical field

The invention relates to the technical field of road safety protection devices, in particular to a guardrail and an installation method thereof.

Background technique

Existing guardrails are divided into rigid guardrails, semi-rigid guardrails and flexible guardrails according to their mechanical properties. The guardrail column is a part of the guardrail and one of the key components that determine the performance of the guardrail.

At present, the design of the domestic guardrail column mainly focuses on the anti-collision performance. Its rigidity is high, and the column rigidity is high. During the collision between the vehicle and the guardrail, it will block the vehicle and cannot change with the collision energy of the out-of-control vehicle. And change, safety performance is low.

Therefore, how to improve the safety performance of the guardrail column has become a technical problem to be solved urgently by those skilled in the art.

Contents of the invention

In view of this, the present invention provides a guardrail to improve the safety performance of the guardrail post. The invention also provides a guardrail installation method.

To achieve the above object, the present invention provides the following technical solutions:

A guardrail, comprising a guardrail post and a steel wire rope connected to the guardrail post, the guardrail post comprising:

The circular arc plate that can be connected with the steel wire rope, the number of the circular arc plate is two, and the concave surface of the circular arc plate is arranged oppositely and connected by welding, and the central angle of the circular arc plate is less than 180°.

Preferably, in the guardrail above, the central angle of the arc plate is 100°-150°, the thickness of the arc plate is 4-8 mm, and the radius of the arc plate is 50-110 mm.

Preferably, in the above guardrail, the arc plate is an arc plate made of low carbon steel material.

A guardrail installation method for installing the guardrail described in any one of the above, comprising the steps of:

1) The guardrail column is pre-embedded, and the plane where the connection of the two circular arc plates is located forms an angle α with the tangent direction of the road, 30°≤α≤60°;

2) Connect the steel wire rope with the guardrail column.

Preferably, in the above guardrail installation method, the steel wire rope is connected to the guardrail post through a hook or through a friction pair between the steel wire rope and the contact surface of the guardrail post.

It can be seen from the above technical solution that the guardrail provided by the present invention includes a guardrail column and a steel wire rope connected with the guardrail column. The guardrail column is welded by two oppositely arranged circular arc plates. The guardrail column is similar to an elliptical structure. This solution provides The guardrail column adjusts the longitudinal and lateral stiffness ratios of the guardrail column by changing the cross-sectional shape of the guardrail column, and the moment of inertia increases accordingly, which also increases the contact area when the accident vehicle collides with the guardrail. During the collision process between the accident vehicle and the guardrail column The collision force is decomposed into two directions along the tangent direction of the road and perpendicular to the tangent direction of the road, which improves the effect of the balanced distribution of energy absorption density and the cooperative force bearing capacity between the guardrail column and the steel wire rope, and improves the safety of the guardrail to a certain extent. safety performance.

The invention also provides a guardrail installation method. During the installation process, the plane where the arc plate of the guardrail column is connected is at an angle of 30°-60° to the tangent direction of the road, which can increase the distance between the guardrail column and the accident vehicle. The contact area between them makes the guardrail post fully absorb energy and improves the safety performance of the guardrail post.

Description of drawings

In order to more clearly illustrate the technical solutions in the embodiments of the present invention or the prior art, the following will briefly introduce the drawings that need to be used in the description of the embodiments or the prior art. Obviously, the accompanying drawings in the following description are only These are some embodiments of the present invention. Those skilled in the art can also obtain other drawings based on these drawings without creative work.

Fig. 1 is the line diagram of arc angle and maximum acceleration provided by the embodiment of the present invention;

Fig. 2 is a broken line diagram of the arc angle and the maximum offset provided by the embodiment of the present invention;

Fig. 3 is a broken line diagram of arc thickness and maximum acceleration provided by an embodiment of the present invention;

Fig. 4 is a broken line diagram of arc thickness and maximum offset provided by the embodiment of the present invention;

Fig. 5 is a line diagram of arc radius and maximum acceleration provided by the embodiment of the present invention;

Fig. 6 is a broken line diagram of arc radius and maximum offset provided by the embodiment of the present invention;

Fig. 7 is a broken line diagram of the angle between the axis of the arc plate and the tangent line of the road and the maximum acceleration provided by the embodiment of the present invention;

Fig. 8 is a broken line diagram of the angle between the axis of the arc plate and the road tangent and the maximum offset provided by the embodiment of the present invention;

Fig. 9 is a schematic structural view of an arc plate provided by an embodiment of the present invention;

Fig. 10 is a top view of the guardrail column provided by the embodiment of the present invention;

Fig. 11 is a front view of the guardrail column provided by the embodiment of the present invention;

Fig. 12 is a schematic structural view of the guardrail column provided by the embodiment of the present invention when no collision occurs;

Fig. 13 is a structural schematic diagram of the guardrail column provided by the embodiment of the present invention after collision;

Fig. 14 is a schematic structural view of the guardrail column provided by the embodiment of the present invention when it is installed.

Detailed ways

The invention discloses a guardrail to improve the safety performance of a guardrail column. The invention also discloses a guardrail installation method.

The following will clearly and completely describe the technical solutions in the embodiments of the present invention with reference to the accompanying drawings in the embodiments of the present invention. Obviously, the described embodiments are only some, not all, embodiments of the present invention. Based on the embodiments of the present invention, all other embodiments obtained by persons of ordinary skill in the art without making creative efforts belong to the protection scope of the present invention.

Please refer to Fig. 1-Fig. 14, Fig. 1 is the line diagram of arc angle and maximum acceleration provided by the embodiment of the present invention; Fig. 2 is the line diagram of arc angle and maximum offset provided by the embodiment of the present invention; Fig. 3 The line graph of arc thickness and maximum acceleration provided for the embodiment of the present invention; Fig. 4 is the line graph of arc thickness and maximum offset provided by the embodiment of the present invention; Fig. 5 is the arc radius provided by the embodiment of the present invention and the broken line diagram of maximum acceleration; Fig. 6 is the broken line diagram of the arc radius and the maximum offset provided by the embodiment of the present invention; Fig. 7 is the included angle and the maximum A broken line graph of acceleration; FIG. 8 is a broken line graph of the angle between the axis of the arc plate and the road tangent and the maximum offset provided by the embodiment of the present invention; FIG. 9 is a schematic structural diagram of the arc plate provided by the embodiment of the present invention; Fig. 10 is a top view of the guardrail post provided by the embodiment of the present invention; Fig. 11 is a front view of the guardrail post provided by the embodiment of the present invention; Fig. 12 is a structural schematic diagram of the guardrail post provided by the embodiment of the present invention when no collision occurs; Fig. 13 It is a schematic structural diagram of the guardrail post provided by the embodiment of the present invention after collision, and FIG. 14 is a structural schematic view of the guardrail post provided by the embodiment of the present invention when it is installed.

A guardrail, comprising a guardrail post and a steel wire rope connected to the guardrail post, the guardrail post comprising:

There are two circular arc plates 1 that can be connected with steel wire ropes, and the concave surfaces of the circular arc plates 1 are arranged oppositely and connected by welding, and the central angle of the circular arc plates 1 is less than 180°.

The guardrail column provided by this scheme is welded by two oppositely arranged circular arc plates 1. The overall guardrail column has a quasi-elliptical structure, and the column is vertically arranged with the ground. , lateral stiffness ratio, under the same material conditions, the guardrail column provided by this scheme can effectively increase the contact area with the accident vehicle, greatly reduce the contact stress during collision, and achieve the effect of balanced distribution of energy absorption density; in addition , the guardrail column provided by this scheme is a hollow column, the strength is lower than that of the guardrail column in the prior art, and the force bearing capacity can be greatly improved in cooperation with the steel wire rope, and the collision energy can be smoothly absorbed, which not only ensures that the guardrail has good anti-collision performance , while ensuring the safety of the occupants in the vehicle, and has the advantages of low cost, easy manufacture, environmental protection and easy construction.

During the collision between the guardrail column provided by this scheme and the vehicle, the energy absorption process is divided into three stages: when the vehicle just comes into contact with the guardrail column, there is the largest contact area between the guardrail column and the accident vehicle. With the balanced distribution of energy absorption density and the maximization of energy absorption, the guardrail column produces slight bending deformation; in the middle of the collision between the vehicle and the guardrail, the vehicle further contacts with the guardrail column, and the arc plate 1 of the guardrail column undergoes further deformation. At this time, the wire rope Cooperate with the guardrail column to bear the collision force, further reduce the vehicle speed and offset; in the later stage of the vehicle collision with the guardrail, under the action of the vehicle collision force, the guardrail column undergoes bending and plastic deformation to absorb the remaining collision energy of the vehicle, and the accident vehicle stops at this time. The guardrail column provided by this scheme can decompose the collision force into two directions during the collision process between the guardrail column and the accident vehicle, one along the tangential direction of the road, and the other along the direction perpendicular to the tangent of the road, which plays a role in decomposing the collision force , to further realize the balanced distribution of energy absorption density and the maximization of energy absorption.

In order to further optimize the above technical solution, in a specific embodiment of the present invention,

The central angle of the arc plate 1 is 100°-150°, the thickness of the arc plate 1 is 4-8 mm, and the radius of the arc plate 1 is 50-110 mm.

For small cars, it is mainly to reduce its maximum acceleration and reduce the risk of passengers. For large cars, it is mainly to reduce its maximum offset to avoid secondary accidents. Therefore, for the different driving conditions of small cars and large cars, the guardrail The parameters of the column will also change accordingly. Refer to Figure 1-Figure 8 to see:

1) Design parameters of the central angle of the circular arc plate 1: for the driving conditions of small cars, the central angle of the circular arc plate 1 is set within the range of 100°-125°. The maximum acceleration of large and small cars shows a linear increasing trend, and the maximum offset shows a linear decreasing trend. Preferably, considering the safety of drivers and passengers in small cars, the smaller the central angle of the arc plate 1, the better; for large cars Driving conditions, the central angle of the circular arc plate 1 is set within the range of 125°-150°, as can be seen from Figure 1 and Figure 2, with the increase of the central angle, the maximum acceleration of large vehicles shows a linear increasing trend, and the maximum offset It shows a linear decreasing trend. Preferably, considering that large vehicles are likely to cause secondary accidents, the larger the central angle of the arc plate 1, the better.

2) The arc thickness design parameters of the arc plate 1: for the driving conditions of small cars, the thickness of the arc plate 1 is set in the range of 4-6mm. The maximum acceleration of large and small cars shows a linear increasing trend, and the maximum offset shows a linear decreasing trend. Preferably, considering the safety of the driver and passengers in the small car, the thickness of the arc plate 1 is as small as possible, and the stiffness is small. Play a good guiding role; for the driving conditions of large vehicles, the thickness of the arc plate 1 is set in the range of 5-8mm, as can be seen from Figure 3 and Figure 4, with the increase of the thickness of the arc, the maximum thickness of the large vehicle The acceleration shows a linear increasing trend, and the maximum offset shows a linear decreasing trend. Preferably, considering that large vehicles are likely to cause secondary accidents, the thicker the arc plate 1, the better, so as to achieve a certain rigidity and effectively block vehicles.

3) Design parameters of the arc radius of the arc plate 1: for the driving conditions of small cars, the arc radius of the arc plate 1 is set within the range of 50-80mm, as can be seen from Figures 5 and 6, with the As the arc radius increases, the maximum acceleration of the small car shows a linear increasing trend, and the maximum offset shows a linear decreasing trend. Preferably, considering the safety of the driver and passengers in the small car, the smaller the arc radius of the arc plate 1 The better, it can effectively buffer the vehicle during the collision process and fully absorb energy; for the driving conditions of large vehicles, the arc radius of the arc plate 1 is set within the range of 80-110mm, as shown in Figure 5 and Figure 6 It can be seen that with the increase of the arc radius of the arc plate 1, the maximum acceleration of the large vehicle shows a linear increasing trend, and the maximum offset shows a linear decreasing trend, and the decrease is relatively fast. Preferably, considering that large vehicles are likely to cause two In the case of an accident, the larger the arc radius of the arc plate 1, the better, which can increase the contact area between the guardrail column and the vehicle and effectively absorb energy.

The invention is derived from crashworthiness topology optimization results. The traditional topology optimization method is generally used for static and simple dynamic optimization. Based on sensitivity analysis, it cannot solve the topology optimization problem of instantaneous loading and complex boundary conditions. This scheme uses crashworthy topology optimization technology to solve transient nonlinear large The continuous topology optimization problem of deformation adopts the variable density method: the variable density method is realized by means of the finite element method, and the material density of each unit is used as a design variable, and the material density can be continuously changed between 0 and 1, and the stiffness and strength of each unit are determined by It is assumed that it conforms to a certain linear relationship with the material density, and after optimization, it is deleted according to the cell density to obtain the optimal topology. This method obtains the optimal material distribution scheme that satisfies both the constraints and the objective function in a given design domain. It only needs the designer to give the design domain, constraints and optimization goals to automatically calculate the optimal topology structure. type. The present invention is based on the collision conditions of A-level guardrails in the "Highway Guardrail Safety Evaluation Standard JTGB05-01-2013", and sets a 200mm*200mm square cross-section column as an optimized area, so that the vehicle's orientation and the internal energy density of the column are consistent Maximization of property and energy absorption is the constraint condition of topology optimization, and the optimization of mass ratio is taken as the goal of topology optimization, and the corresponding results of different mass ratios are comprehensively analyzed to extract the topological configuration.

In order to ensure the strength of the guardrail, the arc plate is made of low carbon steel.

The present invention also discloses a guardrail installation method, which is used to install the above-mentioned guardrail, comprising steps:

1) Pre-embedded guardrail column, the guardrail column is the above-mentioned guardrail column, and the plane where the connection of the two circular arc plates 1 is located forms an angle α with the tangent direction of the road, wherein the range of the α angle is: 30°≤α≤60°, which can Ensure that during the collision, the accident vehicle can have a large area of contact with the guardrail column, so that the guardrail column can fully absorb energy;

2) Connect the steel wire rope to the guardrail column, so that during the collision process, the steel wire rope and the guardrail column are jointly stressed, which can not only ensure the anti-collision ability of the guardrail, but also ensure the guidance of the guardrail.

In order to further optimize the above technical solution, in a specific embodiment of the present invention, the steel wire rope is connected to the guardrail column through a hook or through the friction pair of the contact surface between the steel wire rope and the guardrail column, and the number of layers of the steel wire rope is 2-5 layers. layers, and each layer contains one or more steel wire ropes.

In the middle stage of the collision between the vehicle and the guardrail column, the steel wire rope and the accident vehicle act together on the guardrail column, the two arc plates 1 of the guardrail column are squeezed and deformed, and the upper steel wire rope is ejected upwards, effectively protecting the large bus from straddling Or climb over the protective fence, the two steel wire ropes in the lower layer can effectively protect the small car from getting out, thereby effectively protecting personnel and vehicles.

In addition, in order to further improve the energy absorption effect, the installation angle of the arc plate 1 has certain requirements, and the parameter design of the installation angle is:

For the driving conditions of small cars, the angle between the plane where the two circular arc plates 1 are connected and the road tangent is 30°-45°. It can be seen from Figure 7 and Figure 8 that with the increase of the installation angle, the small The maximum acceleration of the car shows a linear decreasing trend, and the decreasing speed is fast, and the maximum offset shows a linear increasing trend, and the increasing is slow. Considering the safety of the driver and passengers in the small car, it is preferable that the driving conditions of the small car, the circular arc The greater the angle between the axis of the plate 1 and the tangent of the road, the better, to increase the collision area between the guardrail column and the vehicle, so that the column can fully absorb energy; for the driving conditions of large vehicles, the joint of the two arc plates 1 is The angle between the plane and the road tangent is 45°-60°. From Figure 7 and Figure 8, it can be seen that with the increase of the installation angle, the maximum acceleration of the large vehicle is almost stable, and the maximum offset increases linearly. Trend, considering the large mass of the large vehicle itself, resulting in large inertia and prone to secondary accidents, the larger the angle between the axis of the arc plate 1 and the tangent of the road, the better, and the larger the contact area between the vehicle and the guardrail column, play an effective buffer role.

The guardrail column provided by this scheme can be used not only for flexible guardrails, but also for semi-rigid guardrails.

The guardrail provided by this scheme is not only suitable for roadside protection, but also suitable for roadside protection.

The device provided by this scheme can well meet the guardrail safety evaluation index, and has the characteristics of low cost, convenient installation, and low maintenance cost in the later period. When a collision occurs, only the deformed guardrail column needs to be replaced, and the new guardrail The wire rope is fixed.

The above description of the disclosed embodiments is provided to enable any person skilled in the art to make or use the invention. Various modifications to these embodiments will be readily apparent to those skilled in the art, and the general principles defined herein may be implemented in other embodiments without departing from the spirit or scope of the invention. Therefore, the present invention will not be limited to the embodiments shown herein, but is to be accorded the widest scope consistent with the principles and novel features disclosed herein.

Claims (5)

1. a guardrail, comprises fence upright and the wire rope being connected with described fence upright, it is characterized in that, described fence upright comprises:

The arc plate (1) that can be connected with wire rope, the number of described arc plate (1) is two, and the concave surface positioned opposite of described arc plate (1) and being welded to connect, the central angle of described arc plate (1) is less than 180 °.

2. guardrail according to claim 1, it is characterized in that, the central angle of described arc plate (1) is 100 °～150 °, and the thickness of described arc plate (1) is 4～8mm, and the radius of described arc plate (1) is 50～110mm.

3. according to the guardrail described in claim 1, it is characterized in that the arc plate that described arc plate (1) is made for low-carbon steel material.

4. a guardrail mounting method, is characterized in that, for the guardrail as described in claim 1-3 any one is installed, comprises step:

1) pre-buried described fence upright, the plane at the place, junction of two described arc plates (1) becomes α angle with road tangential direction, 30 °≤α≤60 °;

2) described wire rope is connected with described fence upright.

5. according to the guardrail mounting method described in claim 4, it is characterized in that, described wire rope is connected by hook with described fence upright or is connected with the friction pair of described fence upright contact surface by described wire rope.