岩石地基上柱下独立基础弯拉-膨胀破坏模式

Bending-expansion tensile failure of single-column footing on rock foundation

为研究不同宽高比的岩石地基上柱下独立基础的受力特性及破坏模式,制作了6个底面尺寸相同,高度不同的钢筋混凝土独立基础模型试件,并在岩石地基上进行了竖向荷载作用下的受力破坏试验。结合数值模拟计算结果对比分析了不同宽高比的基础试件的破坏模式和受荷全过程的力学特性,提出岩石地基上柱下独立基础的破坏是弯曲拉应力与竖向受压导致基础侧向膨胀而产生的环向拉应力共同作用的结果,两者对基础破坏的贡献程度随基础宽高比变化。该种破坏模式的提出有助于岩石地基上柱下独立基础的合理设计。

To study the mechanical characteristics and failure modes of single-column footing on rock foundation with different width-height ratio, six model specimens with the same dimensions of base and different heights were fabricated and the destruc-tion test on rock foundation was performed. Combined with the theoretical analysis, the analysis of the failure model and stress characteristics of single-column footing with different width-height ratio on rock foundation was completed. The theory that the failure of single-column footing on rock foundation is caused by the bending and tensile stress combined with circumferential ten-sile stress due to lateral expansion because of axial compression The effects of these two types of stress change with the width- to-height ratio. The new failure model can promote the rational design of single-column footing on rock foundation