基于离心模型试验的砂土管涌特性研究

Piping characteristics of sand based on centrifugal model tests

根据离心模拟技术的特点,运用自行研制的离心模拟试验装置,对几种不同颗粒组成的砂土进行了1g重力加速度和Ng离心加速度下的室内管涌试验.在相同试验容器内进行相同颗粒含量、相同密度和相同尺寸的砂土常规试验和离心模拟试验.砂土离心模拟试验结果表明：离心模拟技术可以用来模拟砂土的管涌特性;砂土在Ng离心加速度下的临界水力梯度与1g重力加速度下的临界水力梯度之比为0.8~1.0.

According to the characteristics of centrifuge modeling technology,laboratory piping tests on sand composed by several kinds of particles were performed under gravitational acceleration of 1g and centrifugal acceleration of Ng by use of the self-developed experimental device.The routine tests and the centrifugal model tests on sand samples with the same grain size distribution,density and size were conducted in the same container.The test results show that the centrifuge modeling technology can be used to simulate the piping characteristics of sand.The ratio of the critical hydraulic gradient of sand under Ng to that under 1g is between 0.8 and 1.0.