A working method of an experimental system for bridges

Abstract

A working method of an experimental system for bridges, including a fan, an air inlet, an air outlet, a control valve, an air filter, a main beam segment model, and a control unit; the working method includes: a testing method and an adjustment method; the The test method includes: step 1, the control unit controls the fan to work, the output gas blows to the edge, the acceleration sensor and the anemometer are arranged on the lower surface of the main beam segment model; step 2, when the acceleration When the value sensed by the sensor reaches the preset value in the database, the external blowing device and the external suction device are turned on, and each of the external blowing device and the external suction device is connected with one of the flow rates. In step 3, the anemometer and the flowmeter collect data and output to the controller.

Description

technical field [0001] The invention relates to the field of bridge vortex vibration experiments, in particular to a working method of an experimental system for bridges. Background technique [0002] With the increasing span of bridges, wind-induced vibration has gradually become the main factor restricting the further development of long-span bridges. Vortex vibration is a self-limiting wind-induced vibration phenomenon with both forced and self-excited characteristics, which is caused by the regular vortex shedding generated when the airflow flows over the surface of the structure. The phenomenon of vortex vibration of bridge main beams is not uncommon in practical projects, such as the Rio-Niteroi Bridge in Brazil, the Trans-Tokyo Bay Bridge in Japan, and the Great Belt Bridge in Denmark. East Belt Bridge), the Volga Bridge in Russia, the Verrazzano-Narrows Bridge in the United States, the Xihoumen Bridge in China, the Humen Bridge and the Parrot Island Bridge have all ...

AI Technical Summary

Problems solved by technology

[0004] 1. The experimental system of the prior art controls the wind force through a valve. However, the wind force in the actual situation is often changing rapidly, and there are too many wind force changes, which cannot be simulated one by one.

[0005] 2. In the valves of the prior art, there are composite spools, but the composite spool is often the inner spool as an auxiliary valve, the outer spool as the main valve, and the inner spool is often processed due to its small volume. Difficulty, and the functions and execution area that the small-volume spool can perform are small, which affects the effect

[0006] 3. The valves in the prior art can adjust the flow through the degree of opening and closing, but the control of the degree of opening and closing requires manual or machine control, which greatly increases the cost

[0007] 4. After the spool of the prior art is used for a long time, there will be fouling or maintenance is required. At this time, the spool needs to be disassembled, and the procedure is relatively cumbersome

[0008] 5. The spool through hole of the prior art is often square or circular, ignoring the characteristics of the oval through hole and the benefits brought by the cooperation of different shapes of through holes

[0009] 6. In the multi-channel rotary valve of the prior art, due to too many channels, the gap between the channels is greatly reduced for each additional channel, and there are less places for sealing, which brings difficulties to the processing and installation of the sealing structure

[0010] 7. The valves in the prior art work through a single drive, and there are few double drives, because the support and vibration of the drive parts are a big problem when the double drive is used

[0011] 8. The living and industrial valves in the existing technology are often set separately, but the experimental valve is just the opposite. Because the experimental valve simulates the actual situation but the ratio is greatly reduced, there is an integration requirement for the experimental valve, and ordinary valves obviously cannot meet the integration requirements.

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