基于离心模型试验的黄土湿陷试验新方法研究

黄土湿陷试验方法主要有室内试验和现场浸水试验两种:室内试验方法,大部分情况试验结果很难反映工程实际;现场浸水试验,试验周期长,费用昂贵,因此需要另辟蹊径。以新疆伊犁强烈自重湿陷性黄土为对象,开展了湿陷特性的离心模型试验,并将离心模型试验成果与现场浸水试验成果以及室内试验成果进行了对比,提出了一个基于离心模型试验的黄土湿陷试验新方法。研究表明:黄土湿陷的离心模型试验同样可以采用双线法和单线法进行,离心模型试验得到的侧压力系数变化规律同室内试验得到的侧压力系数变化规律相一致,通过离心模型试验求得的修正系数β_0值与现场浸水试验得到的值相近,证明了基于离心模型试验的黄土湿陷试验新方法可以得到与现场大型浸水试验相近的结果。

New experimental method for loess collapsibility using centrifugal model tests

The methods for loess collapsibility mainly include field immersion testing method and laboratory testing method. A majority of the results of laboratory testing method differ greatly from the engineering practice. The disadvantages of field immersion testing method are high cost and long testing period. Therefore, a different approach is required. A type of strong collapsible loess under overburden pressure from Ili, Xinjiang is tested based on centrifugal model tests. The results of centrifugal model tests are compared with those of field immersion tests and conventional laboratory collapsible loess tests. The experimental study demonstrates that the Single-line and double-line methods are applicable in measuring the loess collapsibility using centrifugal model tests. The coefficient of lateral earth pressure obtained from the centrifugal model tests is comparable with the value measured by the conventional laboratory tests. The results obtained from the centrifugal model tests are proposed using the correction parameter . The good agreement in the experimental study using centrifugal model tests and the field immersion tests shows that the proposed method can be used as an effective method in measuring loess collapsibility.