Analysis of the principle of "resonance free" technology for vibrating pile hammers

1、 The hazards of resonance

Any object or device has its own natural frequency. When the vibration frequency of the vibrating pile hammer is close to or equal to the natural frequency of the vibrating pile hammer, pile and other vibration systems, it will cause strong vibration of the vibrating pile hammer, pile and other vibration systems, which is called "resonance". When resonance occurs, the amplitude of vibration often reaches more than 10 times the normal amplitude.

Due to the vibration of the pile hammer and the system composed of piles, their natural frequencies are often very low, far below the normal vibration frequency of the vibration pile hammer (as indicated by the green marked area in the figure). Generally, vibrating pile hammers need to pass through the "resonance" frequency region (as indicated in yellow in the figure) during the start-up or shutdown process, so there is a phenomenon of "resonance" during both the start-up and shutdown processes.

Resonance phenomenon during start-up and shutdown of ordinary vibration hammer

2、 Basic principle of "resonance free" technology

The core principle of the "resonance free" technology for vibrating pile hammers is to continuously adjust the eccentric moment, so that the vibrating pile hammer is in a state where the eccentric moment is zero when passing through the natural frequency during the starting and stopping process, and no vibration will be generated at this time, thereby avoiding the occurrence of resonance phenomena during the starting and stopping process.

Resonance free start and stop

3、 Technical advantages

Resonance free startup and shutdown

The application of the technology of infinitely adjustable eccentric mass moment avoids the resonance generated during the starting and stopping process of traditional vibration pile hammers with eccentric mass moment, enabling the machine to start and stop smoothly and freely, and preventing unpredictable damage to the vibration pile hammer, pile driver, and immersed tube caused by strong vibration generated by resonance.

Eccentric mass moment infinitely adjustable and controllable

In certain construction application scenarios, the eccentric mass moment can be manually adjusted to control the magnitude of the excitation force and the settling speed, in order to achieve the standard of the vibration hammer.

Resonance free suspension method

By utilizing resonance free technology, the vibration pile hammer can be directly lifted using a lifting method, which has high construction efficiency and can ensure a high degree of verticality.

Reduce startup energy consumption

The resonance free vibration pile hammer can be started under the condition of no eccentric mass moment, that is, no-load starting; Solved the problem of requiring a large capacity power supply for the traditional vibration pile hammer to start under load; The configuration of power supply generally only requires twice the power of the vibration pile hammer motor, which meets the requirements of energy conservation and emission reduction.

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