红层坝基泥化夹层高压射流冲洗置换试验研究

李清波 王贵军 刘庆亮 王俊智

摘 要：红色陆相碎屑岩地层层间剪切带泥化夹层抗剪强度低，对重力坝坝基深层抗滑稳定具有控制性作用，需采取工程措施予以处理。以拟建黄河古贤水利枢纽工程坝基JQD06剪切带泥化夹层为研究对象，开展了高压射流冲洗置换灌浆试验。试验采用孔内高压射流定向切削破坏剪切带泥化夹层原岩结构，冲出软弱碎屑和泥质，通过调整冲洗工艺与冲洗参数优化冲洗效率，并采用水泥浆液对高压射流冲洗后形成的空腔进行灌浆充填置换，从而达到明显提升剪切带泥化夹层抗剪强度的目的。试验结果表明：对近水平发育的红层泥化夹层采用高压射流冲洗置换灌浆处理技术可行，效果良好。

关键词：红层;深层抗滑稳定;剪切带泥化夹层;高压射流冲洗置换;古贤水利枢纽

中图分类号：TV543;TV642.3 文献标志码：A

doi：10.3969/j.issn.1000-1379.2021.05.026

Abstract： Shear-zone muddy interlayers in red clastic strata are characterized by low shear strength， which play a controlling role in the anti-sliding stability of the gravity dam foundation and engineering measures should be taken to deal with it. In this paper， taking the JQD06 shear-zone muddy interlayer of Guxian Dam as an example， the high-pressure jet flushing & grouting experiment was carried out. The high-pressure water vapor jet flushing was used for directional cutting to destroy the original structure of the shear-zone muddy interlayer and washing out the weak debris and mud. The flushing efficiency was optimized by adjusting the flushing process and parameters. The flushed cavities were filled and replaced by grouting， so as to achieve the purpose of significantly improving the shear strength of the shear-zone muddy interlayer. The experiment results show that it is feasible and effective to use the high-pressure jet flushing & grouting technique for the treatment of the horizontally-developed red-bed muddy interlayers.

Key words： red-bed; anti-sliding stability; shear-zone muddy interlayer; high-pressure jet flushing & grouting; Guxian Dam of Yellow River

红层一般指中生代以来的红色陆相碎屑岩地层。红层岩性主要为砂岩、粉砂岩、黏土岩、砾岩、泥质页岩等，具有褶皱不剧烈、产状平缓、软硬岩互层、岩性岩相多变、层间剪切带泥化夹层发育等特点[1]。红层层间剪切带泥化夹层抗剪强度小，作为混凝土重力坝坝基时，通常对其深层抗滑稳定具有控制性作用，需要采取工程措施提高其综合抗剪能力[2]。常见的泥化夹层处理措施包括混凝土置换、混凝土深齿墙、混凝土洞塞等[3]。工程实践中，埋深较小的泥化夹层多采用混凝土置换方法处理，埋深较大的泥化夹层则多采用混凝土深齿墙或混凝土洞塞处理。……