Automatic construction method and system for concrete guardrail

Abstract

The embodiment of the invention provides an automatic construction method for a concrete guardrail. The method is applied to the technical field of engineering construction and comprises the steps that road data and concrete construction data are dynamically collected according to the actual road flow condition, and concrete guardrail structural parameters are generated based on the road data; performing targeted structural reinforcement on the concrete guardrail based on the structural parameters of the concrete guardrail to obtain the concrete guardrail with a reinforced structure; and actual construction installation is conducted based on the concrete guardrail with the reinforced structure, and automatic construction of the concrete guardrail is completed. In this way, the structural parameters are obtained according to the actual working conditions in the road running state, the targeted performance of the concrete guardrail is enhanced, the automation degree is high, manual intervention is greatly reduced, guardrail construction under various complex traffic conditions can be achieved, and high robustness is achieved.

Description

Technical Field

[0001] The present invention disclosure relates to the technical field of engineering construction, and particularly relates to an automated construction method and system for concrete guardrails. Background Art

[0002] The concrete anti-collision guardrail on bridges refers to the guardrail installed on bridges in highways. It is to prevent vehicles from going out of the bridge for various reasons, and to a certain extent, it ensures the safety of people and vehicles. Therefore, the strength requirement of the guardrail is relatively high, and the construction process of the concrete guardrail also has quite strict requirements and specifications.

[0003] Generally, during the production of concrete guardrails, main reinforcement bars are usually set in the guardrails to enhance the strength of the guardrails. Therefore, when the main reinforcement bars of the guardrails enter the construction site, those with large differences in size and shape need to be reprocessed and reshaped to make the shapes and sizes of all the main reinforcement bars of the guardrails consistent. However, in the current construction methods, the influence of actual operating conditions such as road traffic flow on the concrete strength is not considered, making it difficult to apply to actual working conditions.

[0004] Therefore, there is an urgent need for a construction method for concrete guardrails that can effectively target actual road conditions. Summary of the Invention

[0005] The present invention disclosure provides an automated construction method and system for concrete guardrails, which solves the problem that the existing methods do not consider the influence of actual operating conditions such as road traffic flow on the concrete strength and thus are difficult to apply to actual working conditions by obtaining structural parameters according to the actual working conditions under the road operation state and enhancing the targeted performance of the concrete guardrails.

[0006] According to the first aspect of the present invention disclosure, an automated construction method for concrete guardrails is provided, including the following steps: Dynamically collect road data and concrete construction data according to the actual road traffic flow conditions, and generate structured parameters of the concrete guardrail based on the road data; Carry out targeted structural enhancement on the concrete guardrail based on the structured parameters of the concrete guardrail to obtain a concrete guardrail with an enhanced structure; Carry out actual construction and installation based on the concrete guardrail with the enhanced structure to complete the automated construction of the concrete guardrail.

[0007] In the above aspect and any possible implementation manner, a further implementation manner is provided. The process of dynamically collecting road data and concrete construction data according to the actual road traffic flow conditions and generating structured parameters of the concrete guardrail based on the road data and concrete construction data is as follows: Dynamically collect the measured vehicle speed and impact event data of the target section according to the actual road traffic flow, and calculate the dynamic load spectrum based on the road standard design parameters, where the road standard design parameters include the standard design load and the design vehicle speed; Generate a heat map of the stress concentration area based on the dynamic load spectrum, locate the weak area of the guardrail, and generate the concrete strength parameters based on the weak area; Generate the concrete uplift force requirement based on the concrete construction data and the dynamic load spectrum, and obtain the concrete guardrail structural parameters based on the concrete strength parameters and the uplift force requirement.

[0008] For the aspects and any possible implementation manners as described above, a further implementation manner is provided. The process of generating a heat map of the stress concentration area based on the dynamic load spectrum, locating the weak area of the guardrail, and generating the concrete strength parameters is as follows: Simplify the concrete guardrail into a beam subjected to lateral impact, construct a simply supported beam model, and solve for the maximum bending moment and the design shear force based on the dynamic load spectrum and through the mechanical equilibrium equation; Input the dynamic load spectrum into the ANSYS model, output the stress nephogram, mark the positions of the maximum bending moment and the design shear force in the stress nephogram, and obtain the concrete strength parameters.

[0009] For the aspects and any possible implementation manners as described above, a further implementation manner is provided. The process of generating the concrete uplift force requirement based on the concrete construction data and the dynamic load spectrum is as follows: Obtain the self-weight of the guardrail, the coefficient of friction of the foundation soil, and the wind load in the target construction area; Calculate the normal force based on the self-weight of the guardrail and the wind load, and calculate the frictional force based on the coefficient of friction of the foundation soil in combination with the soil conditions to obtain the frictional force contribution; Calculate the overturning moment based on the dynamic load spectrum and determine the total uplift force requirement; Invert the cross-sectional area of the shear key based on the total uplift force requirement, and calculate the shear key contribution; Calculate the uplift force requirement based on the frictional force contribution and the shear key contribution.

[0010] For the aspects and any possible implementation manners as described above, a further implementation manner is provided. The specific uplift force requirement is: ; where μ is the coefficient of friction of the foundation soil, N is the normal force, fy is the yield strength of steel, and Ast is the cross-sectional area of the shear key.

[0011] For the aspects and any possible implementation manners described above, a further implementation manner is provided. The process of performing targeted structural enhancement on the concrete guardrail based on the structural parameters of the concrete guardrail to obtain the concrete guardrail with an enhanced structure is as follows: Obtain the effective height of the concrete cross-section, calculate the cross-sectional area of the longitudinal main steel bars of the concrete based on the maximum bending moment and the effective height of the cross-section, and complete the design of the longitudinal main steel bars of the concrete guardrail; Obtain the cross-sectional area of a single stirrup of the concrete, calculate the spacing of the transverse stirrups of the concrete based on the designed shear force and the cross-sectional area of the single stirrup, and complete the design of the transverse stirrups of the concrete guardrail; Calculate the cross-sectional area of the shear key based on the uplift force requirement and the friction force, and complete the design of the shear key of the concrete guardrail; Obtain the concrete guardrail with an enhanced structure based on the cross-sectional area of the longitudinal main steel bars of the concrete, the spacing of the transverse stirrups of the concrete, and the cross-sectional area of the shear key.

[0012] For the aspects and any possible implementation manners described above, a further implementation manner is provided. The process of performing actual construction and installation on the concrete guardrail with an enhanced structure to complete the automated construction of the concrete guardrail is as follows: Import the model of the concrete guardrail with an enhanced structure constructed into the robotic arm control system, and automatically generate the template installation path and the concrete pouring trajectory; After the pouring is completed and the concrete begins to set, cover the concrete guardrail with a curing film and spray water regularly in an automatic spraying manner, and use a fiber optic sensor to detect the strain distribution inside the concrete, identify the pouring cracks, and perform repairs.

[0013] For the aspects and any possible implementation manners described above, a further implementation manner is provided. The process of using a fiber optic sensor to detect the strain distribution inside the concrete, identify the pouring cracks, and perform repairs is as follows: Collect the tensile strength and elastic modulus of the concrete guardrail during the pouring process through a fiber optic sensor, calculate the critical strain for concrete cracking, and obtain the concrete cracking trajectory; According to the detected concrete cracking trajectory, automatically inject an epoxy resin-nano clay composite material for repair; Perform a secondary scan after the repair. If the crack closure rate ≥ 90%, mark the area as enhanced, otherwise trigger a manual review.

[0014] According to the second aspect of the present disclosure, a concrete guardrail automated construction system is provided, including: a concrete guardrail structural parameter acquisition module, a structural enhancement module, and a construction module; The concrete guardrail structure parameter acquisition module is used to dynamically collect road data and concrete construction data according to the actual traffic conditions of the road, and generate concrete guardrail structure parameters based on the road data; The structure enhancement module is used to perform targeted structure enhancement on the concrete guardrail based on the concrete guardrail structure parameters to obtain a concrete guardrail with an enhanced structure; The construction module is used to perform actual construction and installation based on the concrete guardrail with the enhanced structure to complete the automatic construction of the concrete guardrail.

[0015] The present invention discloses the following technical effects: The present invention obtains structure parameters according to the actual working conditions under the road operation state and performs targeted performance enhancement on the concrete guardrail, and monitors and automatically strengthens the existing cracks after construction. The method of the present invention has a high degree of automation and greatly reduces manual intervention, and can be used for the guardrail construction under various complex traffic conditions, and has strong robustness.

[0016] It should be understood that the content described in the invention content part is not intended to limit the key or important features of the embodiments of the present disclosure, nor is it used to limit the scope of the present disclosure. Other features of the present disclosure will become easily understood through the following description. BRIEF DESCRIPTION OF THE DRAWINGS

[0017] In combination with the drawings and referring to the following detailed description, the above and other features, advantages and aspects of the embodiments of the present disclosure will become more obvious. The drawings are used to better understand the solution and do not constitute a limitation to the present disclosure. In the drawings, the same or similar reference numerals represent the same or similar elements, where: Figure 1 shows a flowchart of a method for automatic construction of a concrete guardrail according to an embodiment of the present disclosure; Figure 2 shows a schematic structural diagram of a system for automatic construction of a concrete guardrail according to an embodiment of the present disclosure. DETAILED DESCRIPTION OF THE EMBODIMENTS

[0018] To make the objectives, technical solutions and advantages of the embodiments of the present disclosure clearer, the technical solutions in the embodiments of the present disclosure will be clearly and completely described below with reference to the drawings in the embodiments of the present disclosure. Apparently, the described embodiments are some, but not all, of the embodiments of the present disclosure. All other embodiments obtained by those of ordinary skill in the art without creative efforts based on the embodiments in the present disclosure belong to the scope of protection of the present disclosure.

[0019] To make the above objectives, features and advantages of the present invention more obvious and understandable, the present invention will be further described in detail below with reference to the drawings and specific embodiments.

[0020] Please refer to Figure 1 , this embodiment provides an automatic construction method for concrete guardrails, including the following steps: S101. Dynamically collect road data and concrete construction data according to the actual traffic flow of the road, and generate structured parameters of the concrete guardrail based on the road data.

[0021] In this embodiment, combining the BIM model with finite element analysis, according to the actual traffic flow, vehicle type distribution and impact probability, define the dynamic load spectrum: (1) Among them, k is the road condition correction coefficient (1.2 for mountainous areas and 1.0 for plains), v 实测 is the average vehicle speed of the section, that is, the measured vehicle speed, v 设计 is the designed vehicle speed, and F 标准 is the standard design load.

[0022] In the above formula, the measured vehicle speed v 实测 and the road condition coefficient k directly affect the amplitude of the load spectrum.

[0023] Based on the generated dynamic load spectrum, real-time collect road data such as impact event data through in-vehicle sensors and road monitoring systems, generate a heat map of the stress concentration area, and locate the weak points of the guardrail (such as the ends of the guardrail and near the expansion joints). In this embodiment, the weak parts of the concrete guardrail include the maximum bending moment area, the shear force concentration area, and the uplift force requirement. The specific calculation method is as follows: Simplify the guardrail into a beam subjected to lateral impact, and solve for the maximum bending moment Mmax through the mechanical equilibrium equation: (2).

[0024] Among them, L is the span of the guardrail, and Vu is the designed shear force.

[0025] Subsequently, input F 动态 into the ANSYS model, output the stress nephogram, and directly mark Mmax (at the bottom 1 / 3 height) and Vu (near the expansion joint) in the stress nephogram, so as to obtain the maximum bending area and the shear force concentration area.

[0026] At the same time, in this embodiment, it is necessary to calculate the uplift force requirement Q 抗拔 , and the specific process is as follows: Obtain the self-weight G of the guardrail in the target construction area, the friction coefficient μ of the foundation soil, and the wind load W; Calculate the normal force N = G + W based on the self-weight G of the guardrail and the wind load W, and calculate the friction force μN based on the friction coefficient μ of the foundation soil in combination with the soil conditions to obtain the friction force contribution; Subsequently, an overturning moment is calculated based on the dynamic load spectrum and the total uplift force requirement is determined, specifically as follows: (3) Where h is the height of the load application.

[0027] Since the overturning moment will cause the tension zone of the foundation to bear a greater uplift force, in this embodiment, the total uplift force requirement needs to satisfy: (4); Where L is the length of the foundation uplift force arm.

[0028] Based on the total uplift force requirement, the shear key cross-sectional area is inverted and the shear key contribution is calculated, specifically as follows: (5); Where fy is the yield strength of the steel.

[0029] Based on the frictional contribution and the shear key contribution, the uplift force requirement is calculated, specifically as follows: (6).

[0030] S102. Based on the structural parameters of the concrete guardrail, the concrete guardrail is structurally enhanced in a targeted manner to obtain a structurally enhanced concrete guardrail.

[0031] In this embodiment, after obtaining the structural parameters of the concrete guardrail, the structural design of the concrete guardrail is carried out. The specific process is as follows: First, the longitudinal main reinforcement is designed to resist the influence of the maximum bending moment, specifically as follows: (7) Where As is the cross-sectional area of the steel bar.

[0032] Secondly, the transverse stirrups are designed to resist the influence of the design shear force, specifically as follows: (8) Where Av is the area of a single stirrup and d is the effective height of the cross-section.

[0033] Finally, the shear key is designed to meet the uplift force requirement, specifically as follows: (9) Where Ast is the area of the shear key.

[0034] S103. Based on the structurally enhanced concrete guardrail, actual construction and installation are carried out to complete the automated construction of the concrete guardrail.

[0035] In this embodiment, the process of actual construction and installation of the concrete guardrail is as follows: Import the constructed concrete guardrail model based on the enhanced structure into the robotic arm control system to automatically generate the template installation path and the concrete pouring trajectory. After the pouring is completed and the concrete begins to set, cover the concrete guardrail with a curing film and spray water regularly in an automatic spraying manner. Use a fiber optic sensor to detect the strain distribution inside the concrete, identify the pouring cracks, and perform repairs.

[0036] Furthermore, in this embodiment, the process of using a fiber optic sensor to detect the strain distribution inside the concrete, identify the pouring cracks, and perform repairs is as follows: Collect the tensile strength and elastic modulus of the concrete guardrail during the pouring process through the fiber optic sensor, calculate the critical strain for concrete cracking, and obtain the concrete cracking trajectory. Specifically: (10) Wherein, is the critical strain for concrete cracking, is the tensile strength, is the elastic modulus.

[0037] Under the action of the load, the crack initiation position is manifested as a sudden increase (compression zone) or sudden decrease (tensile zone) in local strain, forming significant strain peaks / valleys. Therefore, the crack trajectory can be obtained through the critical strain.

[0038] According to the detected concrete cracking trajectory, automatically inject the epoxy resin-nano clay composite material for repair. Among them, the specific amount of glue injection is: (11); Wherein, l is the crack length, w is the width, and D is the depth.

[0039] After repair, perform a secondary scan again. If the crack closure rate ≥ 90%, mark this area as "reinforced", otherwise trigger a manual review.

[0040] As Figure 2 shown, this embodiment also provides an automated concrete guardrail construction system, including: a concrete guardrail structured parameter acquisition module 1, a structure enhancement module 2, and a construction module 3; The concrete guardrail structured parameter acquisition module 1 is used to dynamically collect road data and concrete construction data according to the actual traffic conditions of the road, and generate concrete guardrail structured parameters based on the road data; The structure enhancement module 2 is used to perform targeted structure enhancement on the concrete guardrail based on the concrete guardrail structured parameters to obtain a concrete guardrail with an enhanced structure; The construction module 3 is used for actual construction and installation based on the concrete guardrail after strengthening the structure, and completes the automatic construction of the concrete guardrail.

[0041] It should be noted that for the foregoing method embodiments, for the sake of simple description, they are all expressed as a series of action combinations. However, those skilled in the art should know that the present disclosure is not limited by the described action sequence, because according to the present disclosure, certain steps can be performed in other sequences or simultaneously. Secondly, those skilled in the art should also know that the embodiments described in the specification are all optional embodiments, and the actions and modules involved are not necessarily essential to the present disclosure.

[0042] It should be understood that various forms of the processes shown above can be used, with steps reordered, added, or deleted. For example, the steps recited in the present disclosure can be executed in parallel, sequentially, or in a different order, as long as the desired results of the technical solutions disclosed in the present disclosure can be achieved, and no limitation is imposed herein.

[0043] The above specific implementation manners do not constitute a limitation on the protection scope of the present disclosure. Those skilled in the art should understand that various modifications, combinations, sub - combinations, and substitutions can be made according to design requirements and other factors. Any modifications, equivalent substitutions, and improvements made within the spirit and principles of the present disclosure shall be included within the protection scope of the present disclosure.

Claims

1. A method for automated construction of concrete guardrails, characterized in that: The following steps are involved: Dynamically collect road data and concrete construction data according to actual road traffic conditions, and generate concrete guardrail structural parameters based on the road data; Based on the structural parameters of the concrete guardrail, the concrete guardrail is subjected to targeted structural enhancement to obtain a concrete guardrail with an enhanced structure; The actual construction and installation of the concrete guardrail after the enhanced structure is carried out to complete the automated construction of the concrete guardrail.

2. The automated construction method for concrete guardrail according to claim 1, characterized in that: The process of dynamically collecting road data and concrete construction data according to the actual road traffic conditions, and generating concrete guardrail structural parameters based on the road data and concrete construction data is as follows: Dynamically collect the measured vehicle speed and collision event data of the target road section according to the actual road traffic conditions, and calculate the dynamic load spectrum based on the road standard design parameters, wherein the road standard design parameters include the standard design load and the design vehicle speed; Generate a stress concentration area thermal map based on the dynamic load spectrum, locate the weak area of ​​the guardrail, and generate concrete strength parameters based on the weak area; The concrete pull-out force requirement is generated based on the concrete construction data and the dynamic load spectrum, and the concrete guardrail structural parameters are obtained based on the concrete strength parameters and the pull-out force requirement.

3. The automated construction method for concrete guardrail according to claim 2, characterized in that: The process of generating a stress concentration area thermal map based on the dynamic load spectrum, locating the weak area of ​​the guardrail, and generating concrete strength parameters based on the weak area is as follows: The concrete guardrail is simplified into a beam subjected to lateral impact, a simply supported beam model is constructed, and the maximum bending moment and the design shear force are obtained by solving the mechanical equilibrium equation based on the dynamic load spectrum; The dynamic load spectrum is input into the ANSYS model, and a stress cloud diagram is outputted. The maximum bending moment and the design shear position are marked in the stress cloud diagram to obtain the concrete strength parameters.

4. The automated construction method for concrete guardrail according to claim 3 is characterized in that: The process of generating the concrete pull-out resistance requirement based on the concrete construction data and the dynamic load spectrum is as follows: Obtain the guardrail deadweight, foundation soil friction coefficient and wind load of the target construction area; The normal force is calculated based on the deadweight of the guardrail and the wind load, and the friction force is calculated based on the friction coefficient of the foundation soil combined with the soil conditions to obtain the friction force contribution; Calculate the overturning moment based on the dynamic load spectrum and determine the total pullout force requirement; Inversely calculate the shear key cross-sectional area based on the total pullout resistance requirement, and calculate the shear key contribution; The pull-out force requirement is calculated based on the friction force contribution and the shear key contribution.

5. The automated construction method for concrete guardrail according to claim 4, characterized in that: The pull-out resistance requirement is specifically: ； Among them, μ is the friction coefficient of foundation soil, N is the normal force, fy is the yield strength of steel, and Ast is the cross-sectional area of ​​the shear key.

6. The automated construction method for concrete guardrail according to claim 5, characterized in that: The process of performing targeted structural enhancement on the concrete guardrail based on the structural parameters of the concrete guardrail to obtain the reinforced concrete guardrail is as follows: Obtain the effective height of the concrete section, calculate the cross-sectional area of ​​the longitudinal main reinforcement of the concrete based on the maximum bending moment and the effective height of the section, and complete the design of the longitudinal main reinforcement of the concrete guardrail; The area of ​​the concrete single-leg stirrup is obtained, and the spacing of the concrete transverse stirrups is calculated based on the design shear force and the area of ​​the single-leg stirrup, so as to complete the design of the transverse stirrups of the concrete guardrail; The shear key cross-sectional area is calculated based on the pull-out resistance requirement and the friction force, and the shear key design of the concrete guardrail is completed; A concrete guardrail with a reinforced structure is obtained based on the cross-sectional area of ​​the concrete longitudinal main reinforcement, the spacing of the concrete transverse stirrups and the cross-sectional area of ​​the shear keys.

7. The automated construction method for concrete guardrail according to claim 1, characterized in that: The actual construction and installation of the concrete guardrail based on the enhanced structure to complete the process of automated construction of the concrete guardrail is as follows: Importing the constructed concrete guardrail model based on the enhanced structure into the robotic arm control system to automatically generate a template installation path and a concrete pouring trajectory; After pouring is completed and the concrete has initially set, the concrete guardrail is covered with a curing film and water is sprayed regularly using an automatic sprinkler system. Fiber optic sensors are used to detect the strain distribution inside the concrete, identify pouring cracks, and repair them.

8. The automated construction method for concrete guardrail according to claim 1, characterized in that: The process of using the optical fiber sensor to detect the strain distribution inside the concrete, identify the casting cracks, and repair them is as follows: The tensile strength and elastic modulus of the concrete guardrail during the pouring process are collected by optical fiber sensors, the critical strain of concrete cracking is calculated, and the concrete cracking trajectory is obtained; According to the detected concrete cracking track, epoxy resin-nanoclay composite material is automatically injected for repair; After repair, a second scan was performed. If the crack closure rate was ≥90%, the area was marked as enhanced, otherwise a manual review was triggered.

9. A concrete guardrail automated construction system, implemented by the concrete guardrail automated construction method according to any one of claims 1 to 8, characterized in that: include: Concrete guardrail structural parameter acquisition module (1), structure reinforcement module (2) and construction module (3); The concrete guardrail structural parameter acquisition module (1) is used to dynamically collect road data and concrete construction data according to actual road traffic conditions, and generate concrete guardrail structural parameters based on the road data; The structural reinforcement module (2) is used to carry out targeted structural reinforcement of the concrete guardrail based on the structural parameters of the concrete guardrail to obtain a concrete guardrail with a reinforced structure; The construction module (3) is used to carry out actual construction and installation of the concrete guardrail based on the reinforced structure, thereby completing the automated construction of the concrete guardrail.

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