Effects of Rubber Layer on Lateral Bearing Behaviors of Cone-shaped Hollow Foundation

The cone-shaped hollow foundation (CHF) is a new type of wind power foundation in mountainous area, which overcomes the disadvantages of large amount of traditional foundation concrete, waste soil accumulated in foundation excavation damaging the mountainous environment, lack of certain flexibility and insufficient deformation capacity of upper fan. In this paper, model tests combined with numerical methods are used to analyze the effects of rubber layer on the lateral bearing capacity of the CHF, deflection of the CHF, and the distribution of rock pressure, respectively. Results show that: (1) the super-structure above the CHF is the main part for bearing lateral loads, and in the range of the embedded depth 0.63H from the lid of CHF. It also can be found that, compared to the corresponding the CHF without a rubber layer, the lateral bearing capacity of CHF with a rubber layer slightly decreases under cyclic loading, while the vertical displacement of the foundation significantly reduces as well. The rubber layer decreases rock pressure along the foundation wall by 10%~30%, because the rubber layer absorbs part of the lateral load by its volume deformation, thus extending the service life of the foundation. (2) The rubber layer also plays the role of energy absorption and energy dissipation, so as to reduce the overturning moment acting on the foundation and significantly improve the stability of the foundation. (3) The elasticity of rubber can also improve the flexibility and energy dissipation capacity of foundation, but the energy dissipation capacity is affected by foundation size, rubber layer thickness, rubber elastic modulus and deformation modulus of rock foundation.