The Evaluation of Vibration Load of High-Rise Structures on Swaying Platforms

Due to rising human activity related to sea and ocean exploration, the problem of designing hydrotechnical constructions sustaining considerable vibrations, becomes extremely pressing.  The article analyses the problem of evaluating the reliability of high-rise structures installed on swaying platforms, using a statistical approach. Original information about angular impacts is obtained from the energy spectrum of wave heights that are considered known in the wind speed function. Differential equations of bending of the structure are solved using the method of decomposition of natural fluctuations by forms. Using the wave height smoothing effect by the platform, the energy spectrum of angular accelerations is obtained. It allows determining the waves’ structural parameters and estimating the reliability of the construction based on the probability of non-exceeding the permissible levels of movement and stress (critical values). The developed method can be used in probabilistic evaluation of reliability of oil towers that are installed on swaying platforms exposed to sea waves.

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