粉质黏土中筒型基础沉放的影响范围研究

随着我国近海风电场规模化建造,宽浅式筒型基础得到了越来越多的应用。为了抵抗百米高塔筒产生的巨大弯矩,筒型基础直径达到了40 m。为了准确评估筒型基础在施工期和服役期的地基承载力,有必要研究筒型基础沉放过程对周围土体产生的影响。本文开展了系统的室内模型试验研究,模拟了筒型基础的自重沉放与负压沉放过程,监测了筒基沉放过程中筒内外土体孔隙水压力变化及沉放前后土体强度的改变;基于孔穴扩张理论推导了筒型基础沉放最大径向影响范围的计算公式。研究结果表明:筒型基础在自重沉放阶段对周围径向土体的影响范围为距筒中心2.2倍半径;负压沉放阶段对土体的影响范围为距筒中心1.6倍半径。

Research on the influence scope of bucket foundation installation in silty clay

With the large-scale construction of offshore wind farms in China, the wide and shallow bucket foundation has been widely used. In order to withstand the huge bending moment generated by the 100-me-ter tower, the bucket foundation diameter reaches 40m. In order to accurately evaluate the foundation bear-ing capacity of the bucket foundation during construction and service, it is necessary to study the impact of the bucket foundation installation process on the surrounding soil. In this paper, the indoor model test is carried out, and the self-weight penetration and suction installation processes of the bucket foundation are simulated. The variation of pore water pressure inside and outside the bucket foundation is monitored. The strength of the soil before and after installation is measured. Based on the theory of cavity expansion, the formula for calculating the maximum radial influence scope of bucket foundation installation is derived. The results show that the radial influence scope of the self-weight penetration on the surrounding soil is 2.2 times the radius; the radial influence scope of the suction installation on the surrounding soil is 1.6 times the radius.