CN-121997417-A - Performance-based reinforced concrete bridge double-column pier falling-stone impact resistant design method

CN121997417ACN 121997417 ACN121997417 ACN 121997417ACN-121997417-A

Abstract

The application relates to a performance-based reinforced concrete bridge double-column pier falling-stone impact-resistant design method. The method comprises the steps of obtaining actual terrain rock information, inputting the actual terrain rock information into a convolutional neural network-support vector machine prediction model to obtain a predicted peak falling rock impact force, determining peak dynamic shearing requirements based on the predicted peak falling rock impact force and the bridge pier dynamic shearing requirements, calculating maximum dynamic shearing bearing capacity based on initial bridge double-column pier design parameters, calculating damage indexes based on the peak dynamic shearing requirements and the maximum dynamic shearing bearing capacity, evaluating damage grades of reinforced concrete bridge double-column piers, comparing the damage grades with an impact resistance target, determining the bridge double-column pier design parameters if the damage grades meet the target, and redesigning and evaluating if the damage grades do not meet the target. A performance-based design framework is established, so that a designer can be helped to perform optimal design according to the importance degree of a road and engineering budget without performing experiments and numerical analysis.

Inventors

ZHANG JIN
LI YAO
MO YANGYANG

Assignees

成都理工大学

Dates

Publication Date: 20260508
Application Date: 20260115

Claims (8)

1. A method for designing a reinforced concrete bridge double-column pier anti-falling stone impact based on performance is characterized by comprising the following steps: acquiring actual terrain rock information, and inputting the actual terrain rock information into a convolutional neural network-support vector machine prediction model to obtain a predicted peak falling rock impact force; Determining peak dynamic shear requirements based on the predicted peak falling stone impact force in combination with pier dynamic shear requirements; calculating the maximum dynamic shear bearing capacity based on the initial double-column pier design parameters of the bridge; calculating a damage index based on the peak dynamic shearing requirement and the maximum dynamic shearing bearing capacity, and evaluating the damage grade of the reinforced concrete bridge double-column pier; And comparing the damage grade with an impact resistance target, if the damage grade meets the target, determining the design parameters of the double piers of the bridge, and if the damage grade does not meet the target, redesigning and evaluating the design parameters.
2. The method for designing a performance-based reinforced concrete bridge double pier for resisting a falling stone impact according to claim 1, wherein the step of determining a peak dynamic shear requirement based on the predicted peak falling stone impact force in combination with a pier dynamic shear requirement comprises: And determining a material constitutive model of concrete, steel bars and falling rocks, setting an impact scene, establishing a finite element model of the falling rocks and the bridge, performing a model impact test, and determining dynamic response and damage of the reinforced concrete bridge double-column pier under the impact scene.
3. The method for designing the double-column pier anti-falling rock impact based on the performance of the reinforced concrete bridge according to claim 1, wherein the calculation formula for determining the peak dynamic shear requirement based on the predicted peak falling rock impact force and the pier dynamic shear requirement is as follows: Wherein, the For the peak falling stone impact force, Peak dynamic clipping requirements.
4. The method for designing the reinforced concrete bridge double-column pier against the falling rocks based on the performance according to claim 1, wherein the calculation formula for calculating the maximum dynamic shear bearing capacity based on the initial bridge double-column pier design parameters is as follows: Wherein, the Is the compressive strength of the cylinder of the concrete, Is the diameter of the bridge pier, Is a dynamic shear bearing capacity.
5. The performance-based reinforced concrete bridge double pier anti-falling rock impact design method according to claim 1, wherein the damage level comprises a slight damage level, a moderate damage level, a severe damage and bridge collapse.
6. The performance-based reinforced concrete bridge double-pier falling rock impact design method according to claim 1, wherein the impact resistance target is determined based on importance level, project budget and construction difficulty of roads and bridges.
7. A computer device comprising a memory and a processor, the memory storing a computer program, characterized in that the processor implements the steps of the method of any of claims 1 to 6 when the computer program is executed.
8. A computer readable storage medium, on which a computer program is stored, characterized in that the computer program, when being executed by a processor, implements the steps of the method of any of claims 1 to 6.

Description

Performance-based reinforced concrete bridge double-column pier falling-stone impact resistant design method Technical Field The application relates to the technical field of bridge structure impact resistance design, in particular to a reinforced concrete bridge double-column pier falling stone impact resistance design method based on performance. Background Along with the rapid development of traffic capital construction, a large number of mountain bridges have to be built in poor geological sections due to the limitation of topography, and are easily affected by falling rock disasters induced by earthquakes and debris flows. The falling rocks impact process is rapid and has huge energy, thereby forming a destructive threat to bridge structures and traffic safety, and the falling rocks impact reinforced concrete bridge pier accidents frequently happen in recent years. The double-pier bridge has better lateral resistance than a single-pier bridge, is widely applied to the middle-span and small-span highway bridges, but lacks effective technical support in design of anti-falling stone impact. On one hand, the design concept based on performance is mature and superior in earthquake engineering, but the extension application in the field of impact engineering is very limited, especially for a falling stone impact scene, related research focuses on damage evaluation and residual performance analysis after pier impact, a targeted impact resistance design thought is not formed, direct guidance cannot be provided for engineering practice, on the other hand, the existing regulation and standard still adopt an equivalent static force method to conduct pier impact resistance design, the design concept based on performance is not integrated, the dynamic characteristics of instantaneous impact of falling stone are difficult to match, the design result is either deviated from conservation to cause resource waste, or insufficient protection cannot resist actual impact, and impact resistance reliability and economy of a bridge structure are seriously affected. In summary, the existing design method and research results cannot meet the actual requirements of the mountain double-pier bridge on the rockfall impact resistance, and a scientific impact resistance design system needs to be constructed. Disclosure of Invention Based on the above, it is necessary to provide a design method for preventing the double piers of the reinforced concrete bridge from falling rocks based on the performance aiming at the technical problems. In a first aspect, the application provides a performance-based reinforced concrete bridge double-column pier design method for preventing falling rocks from impact. The method comprises the following steps: acquiring actual terrain rock information, and inputting the actual terrain rock information into a convolutional neural network-support vector machine prediction model to obtain a predicted peak falling rock impact force; Determining peak dynamic shear requirements based on the predicted peak falling stone impact force in combination with pier dynamic shear requirements; calculating the maximum dynamic shear bearing capacity based on the initial double-column pier design parameters of the bridge; calculating a damage index based on the peak dynamic shearing requirement and the maximum dynamic shearing bearing capacity, and evaluating the damage grade of the reinforced concrete bridge double-column pier; And comparing the damage grade with an impact resistance target, if the damage grade meets the target, determining the design parameters of the double piers of the bridge, and if the damage grade does not meet the target, redesigning and evaluating the design parameters. Optionally, in one embodiment of the present application, before determining the peak dynamic shear requirement based on the predicted peak rockfall impact force in combination with the pier dynamic shear requirement includes: And determining a material constitutive model of concrete, steel bars and falling rocks, setting an impact scene, establishing a finite element model of the falling rocks and the bridge, performing a model impact test, and determining dynamic response and damage of the reinforced concrete bridge double-column pier under the impact scene. Optionally, in an embodiment of the present application, the calculation formula for determining the peak dynamic shear requirement based on the predicted peak falling stone impact force and the pier dynamic shear requirement is: Wherein, the For the peak falling stone impact force,Peak dynamic clipping requirements. Optionally, in an embodiment of the present application, the calculation formula for calculating the maximum dynamic shear bearing capacity based on the initial bridge double pier design parameter is: Wherein, the Is the compressive strength of the cylinder of the concrete,Is the diameter of the bridge pier,Is a dynamic shear bearing capacity. Optionally, in one