干湿循环对原状膨胀土强度变化的影响

为了研究自然条件下原状膨胀土经干湿循环过程后的强度变化趋势,以一系列室内试验模拟自然条件下的干湿循环过程为研究基础,通过直剪试验确定膨胀土强度变化趋势。试验结果表明,原状膨胀土经干湿循环后,土体内部形成了不同等级裂隙,土体结构遭到破坏,强度大幅度降低;但随着干湿循环次数的增加,膨胀土强度基本趋于稳定,并与胀缩率的变化趋势基本保持一致。

Effect of Wet-dry Cycling on Undisturbed ExpansiveSoil Strength Variation

In order to study the undisturbed expansive soil strength trend variation,a series of experiments to simulate the dry-wet cyclic process are designed as the research base,and direct shear test is applied here to determine the soil strength variation trend.Experiment results indicate that a series of different size fissures appear,and soil structure is destroyed along with strength greatly being reduced.However,with the dry-wet cyclic times increasing,expansive soil trends to a stable level and almost keeps the same trend with swelling and shrinkage rate.