法向荷载作用下挤压边墙压裂破碎机理试验研究

混凝土挤压边墙技术与传统方法相比,能更好地保证面板堆石坝中垫层料的压实质量、提高坡面防护能力、施工简便、有利于安全度汛等。但现阶段关于挤压边墙的破碎问题的研究较少。针对引起挤压边墙破碎的法向压力荷载作用,运用试验方法,揭示不同配合比、不同搭接长度及受到不同围压的挤压边墙在法向压力荷载作用下的压裂破碎机理。结果表明,水灰比越大、围压越小、搭接长度越小时,裂缝出现的越早,挤压边墙的裂缝最早出现在搭接部位,且逐步向厚度较大的中间部位发展,所有裂缝大致平行,方向近似垂直面板;挤压边墙的最终破坏与水灰比和围压有关,与搭接长度无关,随着水灰比减小或围压增大,挤压边墙的抗压强度增大。研究成果为挤压边墙的力学特性分析提供了理论基础。

Experimental Study on Fracturing Mechanism of Squeezing Side Wall under Normal Load

Compared with the traditional method, the concrete squeezing side wall technology can better guarantee the compaction quality of the cushion material in the face rockfill dam, improve the protection ability of the slope, and its construction is simple, as well as it is beneficial to the flood prevention. However, there is little research on the crushing of squeezing the side walls. In this paper, test method was used to reveal the fracturing mechanism of fracturing side wall under action of normal pressure load at the different mixing ratio, different lap length and squeezing wall with different confining pressure. The results show that the larger the water-cement ratio is, the smaller the confining pressure and the smaller the lap length are, the earlier the cracks appear; The cracks in the extruded side walls appear first in the overlapping parts, and gradually develop toward the middle part with large thickness; All the cracks are roughly parallel, and the direction is approximately vertical panel; The ultimate damage of squeezed side wall is related with water-cement ratio and confining pressure, and has nothing to do with the lap length; With the decreasing water-cement ratio or increasing confining pressure, the compressive strength of the squeezed side wall increases. The research provide a theoretical basis for the analysis of mechanical properties of extruded side wall.