高压挡水堵头顶拱无盖重高压深孔固结灌浆试验

Consolidation Grouting Test of High Pressure Water Retaining Plug Roof Arch without Cover Heavy Pressure Deep Hole

为验证高压挡水堵头后洞段固结灌浆设计参数的合理性,在无盖重、高灌压、深仰孔多难点耦合的情况下,探索并验证合适的固结灌浆分段长度、施工方法和施工工艺,灌前选择渗水量较大的典型区域开展了顶拱无盖重高压深孔固结试验。试验前设置定点观测孔,采用潜孔钻造孔、机械式灌浆塞堵塞、循环式灌浆法从下往上分段灌浆。灌后进行了质量检查,第三方机构进行了声波测速和孔内成像验证,质量检验结果均满足设计要求,减渗效果明显。

In order to verify the rationality of design parameters of consolidation grouting in the back tunnel section of high-pressure water retaining plug, the appropriate section length, construction method and construction technology of consolidation grouting are explored and verified without the coupling of cover weight, high grouting pressure and deep pit hole. Consolidation test of roof arch without cover weight and high pressure deep hole is carried out in a typical area with large water seepage before grouting. Fixedpoint observation holes are set before the test, and down-hole drilling, mechanical grouting plug blocking and cyclic grouting are used to grout from bottom to top in sections. Quality inspection was carried out after grouting. Acoustic velocity measurement and in-hole imaging verification were carried out by third party organizations. The quality inspection results meet the design requirements and the seepage reduction effect is obvious.