公路路基软岩质粗颗粒填料级配及力学性能研究

依托安徽枞阳长江北岸公路工程，开展天然软岩质粗粒土的级配组成分析和不同级配组成的压实土样室内模型动力加载试验，通过监测动态回弹模量变化来探究软岩质粗颗粒填料的力学性质。结果表明:软岩质粗颗粒填料力学性质的主要影响因素是颗粒的级配；对于软岩质粗颗粒填料，结构强度主要取决于其内粗颗粒特别是粗砾组颗粒（20～60 mm）构成的起决定作用的骨架强度，而填充于骨架空隙内的细颗粒对填料结构强度影响次之；软岩质粗颗粒填料在其最佳含水率和最佳P₅及以上粗颗粒含量（60 %～70 %）附近呈现出最高的动态回弹模量，此时填料的级配状况最好，易形成骨架密实型结构，可表现出最好的力学特性。

Study on Gradation and Mechanical Properties of Soft Rocky Coarse Grained Filler for Highway Subgrade

Based on the engineering of the north bank of the Yangtze River in Zongyang, Anhui Province, in this paper, the natural soft rocky coarse grained soil and a gradation composition analysis were carried out and an indoor model dynamic loading test was conducted on the compacted soil samples with different gradation. The mechanical properties of soft rocky coarse grained fillers were explored by monitoring dynamic resilient modulus changes. The results show that, the main factor affecting the mechanical properties of soft rocky coarse grained fillers is the gradation of particles. For soft rocky coarse grained fillers, the structural strength is mainly determined by the strength of the skeleton formed by the coarse particles, especially the coarse gravel group particles （20～60 mm）, which plays a decisive role, and the fine grains filled in the voids of the coarse particle skeleton play an influential role. Soft rocky coarse grained fillers exhibit the highest dynamic resilient modulus around the optimal water content and optimal coarse grain content （60 % to 70 %）, at this time, the gradation conditions of the filler are the best, a dense framework structure is easy to form and the best mechanical properties can be shown.