新疆希尼尔水库极软岩坝基可灌性研究

Test and analysis on groutability of extreme soft rock dam foundation of Xinier Reservoir in Xinjiang Uygur Autonomous Region

新近系砂岩、砂砾岩及泥岩等极软岩互层状地质基础易产生渗流稳定、渗漏损失、不均匀沉陷和砂土液化等地质危害。以新疆希尼尔水库极软岩坝基除险加固帷幕灌浆试验段施工为例,发现该地层用普通水泥灌浆可灌性差,且灌后难以达到理想的防渗效果。鉴于此,研究了可灌比值、地基渗透系数(K)、地层中细颗粒含量及地层的颗粒级配指标,并判定其可灌性。结果表明,地层颗粒级配指标与可灌比值可初步判定地层可灌性。研究成果可为类似工程判断地基可灌性提供参考。

The interbedded geological foundation of extreme soft rock such as Neogene sandstone, glutenite and mudstone is prone to geological hazards such as seepage stability, seepage loss, uneven settlement and sediment-earth liquefaction.In view of these problems, taking the construction of curtain grouting test section for danger removal and reinforcement of Xinier Reservoir as an example, the poor groutability of ordinary cement grouting in this stratum and the difficulties for achieving the ideal anti-seepage effect after grouting are introduced.The groutable ratio, foundation permeability coefficient(K),the content of fine particles in the formation and the particle grading index of the formation are analyzed and studied to determine the groutability.The results show that the groutability of formation can be preliminarily determined by the ratio of formation particle gradation index to groutability, which can provide a reference for similar projects to judge the groutability of foundation.