不同改良剂对不同含砂率粉土改良性质研究

Study on improving properties of different modifiers on silt with different sand content

通过人工室内配制不同含砂率(10%、20%、40%)粉土,对其进行改良试验,研究在不同改良剂(石灰+水玻璃、石灰+粉煤灰)、不同配比作用下3种含砂率粉土的改良效果,研究结果表明:随着含砂率的增加,无论是素土还是改良土,其最大干密度均增大;对于石灰+水玻璃改良土,其最大干密度较素土有明显的降低,而石灰+粉煤灰改良土与之相反;石灰+水玻璃改良土最优含水率与素土略有差别,而石灰+粉煤灰改良土与素土最优含水率基本一致;在同一含砂率下,对于不同配比的石灰+水玻璃改良土,其最大压实度和最优含水率并未发生较大变化,10%石灰+20%粉煤灰的压实度高于其他配比情况;在恒定压实度(95%)下,改良土的无侧限抗压强度明显高于素土的无侧限抗压强度,改良剂对粉土起到一定的"维稳"效果,改良剂掺量才是决定无侧限抗压强度的关键因素。

A series of artificial silt with different sand ratios （10% ,20%, 40%） is prepared, with the improvement tests, the improvement effect of different modifiers（lime and sodium silicate, lime and fly ash） with different proportion on silt has been investigated, the results show that with the increase of sand rate, either soil or modified soil, the maximum dry density increases; contrary to the lime and fly ash modified soil, the maximum dry density of lime and sodium silicate modified soil is significantly reduced; the optimum moisture content of lime and sodium silicate modified soil and soil is slightly different, however, for lime, fly ash modified soil and soil, the optimum moisture content is basically the same; with the same sand ratio, the maximum degree of compaction and the optimum moisture content of the lime and sodium silicate modified soil with different ratios have not changed greatly, the compaction ratio of 10% lime and 20% fly ash is higher than the others; at a constant degree （95%） of compaction, the unconfined compressive strength of modified soil is significantly higher than silt, and plays a ＂stable＂ effect, the modified additive quantity is the key factor of the unconfined compressive strength.