Vibrating Machines For Sheet Piling, Piling And Pipe Driving: Introductory Remarks

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Vibratory machines for plunging sheet piles, piles and pipes into the ground should be classified according to the type of dynamic effect on the immersed body, the device diagram. and drive type.

According to the first sign, these machines are divided into two main groups: pure vibratory action – vibratory hammers and the so-called vibratory-impact drivers, which, in addition to periodic perturbing forces, also impart periodic shocks to the immersed body.

Vibrators, in addition, can differ in the type of disturbing forces, or, which is essentially the same thing, in the form of the excited vibrations.

Almost all existing types of vibratory drivers are designed so that the disturbing forces arising during their operation act along one line coinciding with the longitudinal axis of the submerged body, and, thus, are capable of causing only pure longitudinal vibrations of this body.

Currently, work is underway to create such vibratory drivers that will be able to excite not only longitudinal, but also rotational vibrations of the submerged body, which has a beneficial effect when immersing shell piles, descent wells, etc.

According to the scheme of the device, the machines of the first group are divided into vibratory pile drivers of the simplest type and with sprung surcharge; the latter, in turn, differ in the type of loading, which can be carried out by attaching special loads to the sprung part of the machine or by transferring to it part of the weight of a lifting device (crane), which is put into action using a winch, jack or other mechanism. In the latter case, the pile driver (or crane), together with the vibratory driver, constitutes one common vibro-pressing unit, capable of combining very significant pressures on the piles being driven with intense vibrations.

Schemes for the device of vibration-impact plungers are diverse; their description will be given below.

According to the type of drive, all currently used vibratory hammers and impact-vibration hammers are electric machines driven by electric motors.

Attempts to create electromagnetic (K. P. Dobryshevsky) and pneumatic (P. V. Melentiev [34]) vibratory drivers have not yet yielded the desired results.