宽级配砂土基料-滤层系统的室内模型试验研究

Lab Model Testing on Piping-filter Prevention in Broadly Graded Sandy Soil

基料-滤层利用数码可视化跟踪技术、计算机信息实时处理技术和土体变形无标点量测技术,对宽级配基料-滤层系统进行了渗透室内模型试验。探讨了滤层准则的适用性,研究了不同滤层厚度和加压速率对管涌发生发展的影响。结果表明:传统太沙基滤层准则不适用于宽级配砂土,建议采用可移动颗粒中的d_(85s)。进行滤层准则设计;增加滤层厚度可提高系统的抗渗透破坏能力,但提高滤层厚度对提高整个系统抵抗渗透能力作用不大;水力梯度增加较快不利于系统的稳定。

By using visual tracing techniques, real-time digital process techniques and non-target measuring techniques,the lab model tests on base soil-filter of broadly graded sandy soil were carried out. The applicability of the filter-layer standard has been discussed; different filter layer thickness and compression rate on piping development influence has invested. The resuits proved that： the traditional Terzaghi filter guideline is improper for broadl graded sand, d85 of moving particles can be used in the design guideline; Increasing filter layer thickness could improve that the system of the seepage failure, but the system penetration ability only improved a little; hydraulic gradient increases faster is not conducive to the stability of the system.