Reflected waves from bored or CFA piles of large section in the offshore soils

UDK: 624.501

Key words: wave processes, bored piles , rarefaction wave, elastic waves, elasto-plastic waves, offshore soils, pressure

Authors: L.F.Aslanov (Azerbaijan University of Architecture and Construction, the Republic of Azerbaijan,Baku)

The problems of the reflection of the waves on the surface of the pile foundation, from the most dense weakly compressible shelf base and in water are considered. The parameters of the reflected wave at the piles of large section with "hard core" are determined. The design parameters of the reflected wave of bored-bit or CFA piles of large cross section that are required for the calculation of offshore structures subjected to the dynamic effects of different types of waves are determined. The grounds of pile foundations consisting of most dense (less compressible) shelf clay soils (solid or semi-solid clays) are considered. This medium is relatively more compressible than the surface of the pile, but less compressible then ground base underlying layer of soil. Soil is taken as ternary medium consisting of air, water and solid particles. Each component is determined separately and the ratio of parameters of air in the composition of the soil to the total volume is calculated. In the presence of entrapped air in offshore soil rheological model of soil describing the non-linear properties is used. Reflection of waves from a large section constructions of the pile depending on the soil properties and shelf-pressure in the incident wave are determined by the reflection coefficient. The underlying layer or the second medium in front of the shock wave is considered as a special case. Under the shock wave this weak second layer stays fixed. The approximations method is implemented.
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