不同含石量下土石混合体重型击实试验研究

A study on heavy compaction test of soil-rock mixtures under different rock contents

为研究含石量对于土石混合体击实效果的影响,对不同含石量的土石混合体进行室内重型击实试验.首先根据客运铁路路基碎石土级配,配置35%、45%、55%、65%含石量的土石混合体试样,进行室内击实试验,得出土石混合体含石量与最优含水量或最大干密度的关系曲线.结果表明:不同含石量的土石混合体最优含水量在(5.5±1.0)%之间,最大干密度在(2.40±0.05)g/cm3范围内,含石量对土石混合体最大干密度影响较小.最大干密度相似的两组土石混合体,其颗粒级配、含石量会相差很大,因此对于土石混合体这类级配多变的岩土复合材料不能单独根据干密度来判断其工程压实效果.研究结果可为土石混合体材料的工程应用提供借鉴和依据.

In order to study the effect of rock content on the compaction effect of soil-rock mixture,heavy compaction test was carried out on soil-rock mixtures with different rock content.Firstly,according to the gradation of the gravel soil of passenger railway subgrade,the soil-rock mixtures sampled with the rock content of 35%,45%,55%and 65%are allocated,respectively for the indoor compaction tests,and the relation curve between the rock content of the soil-rock mixtures and the optimal moisture content or the maximum dry density was obtained.The results show that:The optimal moisture content of soil-rock mixtures with different rock content is between(5.5±1.0)%,and the maximum dry density is in the range of(2.40±0.05)g/cm3,the influence of rock content on the maximum dry density of soil-rock mixture is small.Two groups of soil-rock mixtures with similar maximum dry density have great differences in grain gradation and rock content.Therefore,the degree of engineering compaction of geotechnical composites with variable gradation,such as soil-rock mixtures,can not be judged by dry density alone.The results can provide reference and basis for the engineering application of soil-rock mixtures.