Testing and evaluation methods for energy dissipation performance of steel-composite anti-collision facility structures

Abstract

The present invention relates to a testing and evaluation method for the energy consumption performance of a steel-composite anti-collision facility structure; it belongs to the field of road and bridge anti-collision facility testing. In this step, a pendulum device is used to impact the steel-composite anti-collision facility, and a speed sensor is used to obtain the instantaneous motion speed of the pendulum device before impacting the steel-composite anti-collision facility and the instantaneous motion speed of the pendulum device when it is separated after impacting the steel-composite anti-collision facility. The kinetic energy reduction value of the pendulum device is obtained by calculation, and the kinetic energy reduction value is used to evaluate the steel-composite anti-collision facility. This method proposes a method for calculating the energy consumption capacity of anti-collision facilities based on the instantaneous speed and kinetic energy theorem before and after the impact, and formulates a clear evaluation standard level. The evaluation steps are clear and easy to implement, the comparison results are intuitive, and can fully reflect the characteristics of the structural energy consumption performance, adapt to the actual needs of the project, and have a good guiding significance for the production and development of steel-composite anti-collision facilities.

Description

Technical Field

[0001] The invention relates to a method for testing and evaluating the energy consumption performance of a steel-composite material anti-collision facility structure, and belongs to the field of road and bridge anti-collision facility testing. Background Art

[0002] With the increasing number of bridges and the growing demand for shipping, the probability of the piers of waterway bridges being hit by ships has greatly increased, and there have been many accidents of ships hitting bridge piers and causing damage at home and abroad. Ship-bridge collision accidents not only threaten the safety of ship traffic, but also seriously affect the operational safety of bridges, bring huge threats to personal safety and property losses, and sometimes cause ecological disasters.

[0003] In order to reduce the economic losses caused by accidents such as ship-bridge collisions and improve the safety of public infrastructure, waterway bridges are currently generally equipped with pier anti-collision facilities that combine steel and fiber composite materials (i.e., steel-composite materials), including fixed and floating types. However, the quality of steel-composite anti-collision facilities produced by many manufacturers varies, the energy consumption performance is unknown, and the protection effect is uncertain. Product quality standards are missing, and a unified evaluation system has not yet been established. Designers have difficulties in formulating bridge anti-collision facility plans.

[0004] In the patent document with publication number CN214363166U, a steel-clad composite fixed pier anti-collision facility is disclosed. The patent consists of a composite shell and a closed-cell performance material filled with an inner cavity. Fixing holes are set on the composite shell, and chemical bolts are used to fix it to the pier. The protection performance of the anti-collision facility on the pier in this patent is unclear, and the energy consumption performance of the structure during a ship collision is unknown, making it difficult to compare with other anti-collision facilities.

[0005] In the patent document with publication number CN112431120A, a floating steel-clad composite material bridge anti-collision facility is disclosed; the outer shell of the patent is a steel-clad composite material plate, and the interior is a composite material anti-corrosion layer, a steel plate, a composite material buffer tube and an energy-absorbing closed-cell material, and the mechanical properties of each material are specified; in this patent, there is no measurement indicator for the energy consumption of the structure under the action of impact, and its energy consumption performance cannot be obtained intuitively.

[0006] In summary, the energy dissipation capacity of the anti-collision facility structure is an important protective indicator for absorbing the kinetic energy of the ship and reducing the impact energy of the ship on the bridge piers. Insufficient energy dissipation capacity of the anti-collision facility will cause most of the ship's kinetic energy to be absorbed by the bridge piers, which may cause damage to the piers and even affect the safe operation of the bridge. Therefore, the assessment of the energy dissipation capacity of the anti-collision facility has extremely important guiding significance for the design and selection of bridge anti-collision schemes, and can also be used to guide the structural design, production and formulation of future development directions of anti-collision facilities. Therefore, providing a test and evaluation method for the structural energy dissipation capacity of steel-composite anti-collision facilities has important practical significance and broad application prospects. Summary of the invention

[0007] In view of the above problems, the present invention provides a method for testing and evaluating the energy dissipation performance of a steel-composite material anti-collision facility structure.

[0008] The present invention adopts the following technical solution:

[0009] The test method for the energy dissipation performance of the steel-composite material anti-collision facility structure of the present invention is based on a pendulum device composed of a heavy hammer punch, a mass counterweight block and a suspension arm to impact the steel-composite material anti-collision facility. A piezoelectric force sensor is provided inside the impact part of the heavy hammer punch. A velocity sensor is used to monitor the instantaneous velocity of the heavy hammer punch before and after the impact in the pendulum device. The test evaluation method is as follows:

[0010] Step 1: According to the structural mechanical properties of the steel-composite material anti-collision facility, a suitable pendulum mass and impact height are selected, and the heavy hammer punch of the pendulum device impacts the center point of the front steel plate of the steel-composite material anti-collision facility;

[0011] Step 2: During the impact of the pendulum device on the steel-composite material anti-collision facility, a velocity sensor is used to obtain an instantaneous motion velocity v1 of the pendulum device before impacting the steel-composite material anti-collision facility and an instantaneous motion velocity v2 of the pendulum device when it separates from the steel-composite material anti-collision facility;

[0012] Step 3: Calculate the kinetic energy reduction value of the pendulum device during the impact process using the following formula according to the instantaneous motion speed v1 of the pendulum device before the impact and the instantaneous motion speed v2 of the pendulum device after the impact obtained in step 2;

[0013]

[0014] Where: ΔE——the decrease in kinetic energy of the pendulum device during the impact process, E k1 ——Instantaneous kinetic energy of the pendulum before impact, E k2 ——Instantaneous kinetic energy of the pendulum after impact, m——mass of the pendulum, v1——instantaneous velocity of the pendulum before impact, v2——instantaneous velocity of the pendulum after impact;

[0015] The method for testing the energy dissipation performance of the steel-composite material anti-collision facility structure of the present invention and the method for evaluating the energy dissipation performance of the steel-composite material anti-collision facility structure are as follows:

[0016] Step 1: If the kinetic energy reduction value of the pendulum device during the impact is ΔE>0.4E k1 , then the energy dissipation performance of the steel-composite material anti-collision facility structure is good;

[0017] Step 2: If the kinetic energy of the pendulum device decreases by 0.2E during the impact k1 <ΔE<0.4E k1 , then the energy dissipation performance of the steel-composite material anti-collision facility structure is medium;

[0018] Step 3: If the kinetic energy reduction value of the pendulum device during the impact is ΔE<0.2E k1 , the energy consumption performance of the steel-composite material anti-collision facility structure is poor.

[0019] The method for testing the energy consumption performance of the steel-composite material anti-collision facility structure described in the present invention is to configure the mass of the pendulum device through the number of mass counterweight blocks, the mass counterweight block is arranged at the bottom end of the boom, and a heavy hammer punch is provided at the impact end of the mass counterweight block.

[0020] Beneficial Effects

[0021] The method for testing and evaluating the energy consumption performance of the steel-composite material anti-collision facility structure provided by the present invention integrates multiple characteristic indicators, has clear standards, clear steps, strong operability, good economy and scalability, and is a powerful supplement to the blank of the existing testing and evaluation system in the field of anti-collision facilities.

[0022] In terms of test methods, the test facilities used in this method are simple, occupy a small area, use common sensors, and are easy to purchase. This method can adapt to the testing of steel-composite anti-collision facilities of different sizes and different structural arrangements, and has good promotion. The test process is semi-automatic, triggered by test personnel, and automatically collected and recorded by sensors. The personnel are far apart, which is highly safe and easy to operate. The evaluation indicators of the structural energy consumption performance of the anti-collision facility are easy to collect, and data extraction and calculation are convenient.

[0023] In terms of evaluation methods, this method is based on a large amount of engineering evaluation experience, proposes a calculation method for the energy consumption capacity of anti-collision facilities based on the instantaneous velocity and kinetic energy theorem before and after the impact, and formulates clear evaluation standard levels. The evaluation steps are clear and easy to implement, the comparison results are intuitive, and can fully reflect the characteristics of the structural energy consumption performance, meet the actual needs of the project, and have a good guiding significance for the production and development of steel-composite anti-collision facilities. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1The figure is a flow chart of the test and evaluation method of the present invention.

[0025] Figure 2 It is a schematic diagram of the overall structure of the impact testing device of the present invention.

[0026] Figure 3 It is the arrangement diagram and connection schematic diagram of each sensor of the present invention. DETAILED DESCRIPTION

[0027] In order to make the purpose and technical solution of the embodiment of the present invention clearer, the technical solution of the embodiment of the present invention will be clearly and completely described below in conjunction with the drawings of the embodiment of the present invention. Obviously, the described embodiment is a part of the embodiment of the present invention, not all of the embodiments. Based on the described embodiment of the present invention, all other embodiments obtained by ordinary technicians in this field without creative work are within the scope of protection of the present invention.

[0028] As shown in the figure: the pendulum device 2 includes a heavy hammer punch 21, a mass counterweight block 22 and a suspension arm 23. A hinged portion is provided at the top of the pendulum device 2. The pendulum device 2 is dragged to different heights to generate different impact loads.

[0029] As shown in the figure, the data acquisition system 4 used in the test evaluation method includes a speed sensor 31, a data acquisition instrument 32 and a data storage device 33.

[0030] The velocity sensor 31 is arranged at a corresponding position near the impact point on the side of the concrete rigid wall 1. The velocity sensor 31 is connected to the data input end of the data acquisition device 32 through a data line; and the output end of the data acquisition device 32 is connected to the input end of the data storage device 33.

[0031] Embodiment 1:

[0032] Step 1: Install a certain number of mass counterweights 22 on the pendulum device 2 so that its mass reaches 1000 kg.

[0033] A steel-composite material anti-collision facility 3 is arranged on the concrete rigid wall 1, and a speed sensor 31 is arranged at a corresponding position near the impact point on the side of the concrete rigid wall 1. The speed sensor 31 is a photoelectric gate speed sensor.

[0034] The data of the speed sensor 31 is transmitted to the data acquisition device 32 and after signal processing, enters the data storage device 33 for storage.

[0035] Step 2: Number and fix a certain type of steel-composite material anti-collision facility with a thickness of 300mm; according to the structural mechanical properties of this type of steel-composite material anti-collision facility, select a suitable pendulum mass of 1000kg and an impact height of 0.459m, so that the theoretical speed when it swings to the lowest point is 3m / s. Use a hand chain hoist to lift the 1000kg pendulum to a height of 0.459m, release the unhooker to allow the pendulum to swing freely downward around the upper fixed hinge, and the gravitational potential energy of the pendulum is converted into kinetic energy during the movement. The pendulum swings downward from the above height and collides with the steel-composite material anti-collision facility, subjecting it to an impact load; each sensor collects data such as the speed of the pendulum during the impact loading process, and transmits it to the data storage device for storage.

[0036] Step 3: The steel-composite material anti-collision facility has a thickness of h = 300 mm and a mass of 1000 kg. The pendulum is loaded from a height of 0.459 m. During the impact of the pendulum device on the steel-composite material anti-collision facility, a photoelectric gate speed sensor is used to obtain the instantaneous movement speed v1 = 3.11 m / s before the pendulum device impacts the steel-composite material anti-collision facility, and the instantaneous movement speed v2 = 2.43 m / s when the pendulum device separates after impacting the steel-composite material anti-collision facility.

[0037] Step 4: Calculate the kinetic energy reduction value of the pendulum device according to the obtained instantaneous velocity v1 before impact and instantaneous velocity v2 after impact by the following formula;

[0038]

[0039] Where: ΔE——the decrease in kinetic energy of the pendulum device during the impact process, E k1 ——Instantaneous kinetic energy of the pendulum before impact, E k2 ——Instantaneous kinetic energy of the pendulum after impact, m——mass of the pendulum, v1——instantaneous velocity of the pendulum before impact, v2——instantaneous velocity of the pendulum after impact;

[0040] Step 5: The kinetic energy reduction value of the pendulum during the impact process obtained in step 4:

[0041]

[0042]

[0043] 0.2E k1 <ΔE<0.4E k1

[0044] The kinetic energy reduction value of the pendulum ΔE is consistent with 0.2E k1 <ΔE<0.4E k1 The energy consumption performance of the steel-composite material anti-collision facility structure is medium, and the structural layout needs to be further optimized.

[0045] The above is only a preferred specific embodiment of the present invention, but the protection scope of the present invention is not limited thereto. Any changes or substitutions that can be easily thought of by a person skilled in the art within the technical scope disclosed by the present invention should be included in the protection scope of the present invention. Therefore, the protection scope of the present invention should be based on the protection scope of the claims.

Claims

1. A method for testing and evaluating the energy dissipation performance of a steel-composite material anti-collision facility structure, characterized in that: A pendulum device consisting of a heavy hammer punch, a mass counterweight and a suspension arm is used to impact the steel-composite anti-collision facility. A piezoelectric force sensor is provided inside the impact portion of the heavy hammer punch. A velocity sensor is used to monitor the instantaneous velocity of the heavy hammer punch in the pendulum device before and after the impact. The test method is as follows: Step 1: According to the structural mechanical properties of the steel-composite material anti-collision facility, a suitable pendulum mass and impact height are selected, and the heavy hammer punch of the pendulum device impacts the center point of the front steel plate of the steel-composite material anti-collision facility; Step 2: During the impact of the pendulum device on the steel-composite material anti-collision facility, a velocity sensor is used to obtain an instantaneous motion velocity v1 of the pendulum device before impacting the steel-composite material anti-collision facility and an instantaneous motion velocity v2 of the pendulum device when it separates from the steel-composite material anti-collision facility; Step 3: Calculate the kinetic energy reduction value of the pendulum device during the impact process using the following formula according to the instantaneous motion speed v1 of the pendulum device before the impact and the instantaneous motion speed v2 of the pendulum device after the impact obtained in step 2; Where: ΔE——the decrease in kinetic energy of the pendulum device during the impact process, E k1 ——Instantaneous kinetic energy of the pendulum before impact, E k2 ——Instantaneous kinetic energy of the pendulum after impact, m——mass of the pendulum, v1——instantaneous velocity of the pendulum before impact, v2——instantaneous velocity of the pendulum after impact; The energy consumption performance evaluation method of the steel-composite material anti-collision facility structure is as follows: Step 1: If the kinetic energy reduction value of the pendulum device during the impact is ΔE>0.4E k1 , then the energy dissipation performance of the steel-composite material anti-collision facility structure is good; Step 2: If the kinetic energy of the pendulum device decreases by 0.2E during the impact k1 <ΔE<0.4E k1 , then the energy dissipation performance of the steel-composite material anti-collision facility structure is medium; Step 3: If the kinetic energy reduction value of the pendulum device during the impact is ΔE<0.2E k1 , the energy consumption performance of the steel-composite material anti-collision facility structure is poor.

2. The method for testing and evaluating the energy dissipation performance of the steel-composite material anti-collision facility structure according to claim 1, characterized in that: The mass of the pendulum device is configured by the number of mass counterweight blocks. The mass counterweight block is arranged at the bottom end of the boom, and a heavy hammer punch is arranged at the impact end of the mass counterweight block.

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