压实黄土变形特性研究与应用

黄土高填方成为岩土工程领域新的研究课题，研究前景非常可观。针对延安新区黄土高填方工程做了大量的室内压缩固结试验和增湿变形试验，讨论了压实黄土的变形特性，构造了压实黄土应力-应变关系的最佳拟合模型，并且利用试验数据对百米高填方在不同压实度条件下的压缩固结变形量及增湿变形量进行了预测，分析了各种变形量所占的比例。结果表明，（1）压实黄土在侧限条件下的应力-应变关系可以用Gunary模型拟合；（2）压实黄土在低压实度时低压下产生湿陷变形，高压不产生，中等压实度时低压下不产生湿陷性变形，但高压产生；随着压实度的继续增大，低压及高压下均不产生压实黄土的湿陷性变形；（3）在最优含水率条件下，利用试验数据对百米高填方在不同压实度下的工后沉降量进行预测，可指导现场施工并检验施工质量；（4）压实黄土压实度越高，总变形量越小，遇水增湿变形量占总变形量的比例越大，压缩固结变形量占总变形量的比例越小。

Study and application of deformation characteristics of compacted loess

The high loess-filled project research is a new research topic in the field of geotechnical engineering with impressive prospects. In this paper, indoor compression consolidation and moistening tests are carried out for high loess-filled project researches in Yan’an new district; the influence factors of deformation characteristics of compacted loess are analyzed; the best fitting model of vertical pressure and strain of compacted loess is built; and also, the consolidation and moistening settlements of the 100 m high project are predicted under different compactnesses. The results show that: (1) The vertical pressure-strain curves of compacted loess can be expressed with Gunary model. (2) The lower compactness of compacted loess will produce collapsibility deformation under lower pressure, higher pressure does not; the moderate compactness does not produce collapsible deformation under lower pressure, but higher pressure does; with the continued increase of compactness, the compacted loess does not produce collapsibility deformation under both lower and higher pressure. (3) Under the condition of optimum water content, the settlements of the 100 m high project are predicted under different compactnesses, so as to guide the field compaction and test the quality of construction. (4) The higher the compactness of compacted loess is, the smaller the total amount of deformation is, the greater the amount of water moistening deformation ratio of the total amount of deformation is, the lesser the consolidation compression deformation ratio of the total amount of deformation is.