研究了风化砂改良膨胀土的无侧限抗压强度与风化砂掺量、冻融循环次数之间的定性和定量关系。在膨胀土中分别掺入0,10%,20%,30%,40%,50%的风化砂,在经过0,1,3,6,9,12次冻融循环后,在万能试验机上进行无侧限抗压强度测试。试验结果表明在同一冻融循环次数下,风化砂改良膨胀土的无侧限抗压强度随掺砂比例的增大总体呈现先增大后减小的趋势,当掺砂比例为10%时,风化砂改良膨胀土试样的无侧限抗压强度最大;在同一掺砂比例下,风化砂改良膨胀土的无侧限抗压强度随冻融循环次数的增大而减小,其降低的幅度随冻融循环次数的增大也呈减小的趋势;对试验数据进行回归分析,建立无侧限抗压强度与冻融循环次数之间的数学模型,二者之间表现出良好的自然对数关系,且无侧限抗压强度与冻融循环次数的自然对数呈线性负相关关系。

Qualitative and quantitative relationships among unconfined compressive strength of expansive soil improved by weathered sand, weathered sand content and freeze-thaw cycle were researched. Expansive soil samples were improved by weathered sand with different blending ratios (0, 10%, 20%, 30%, 40%, 50%) and were put in universal testing machine to test the unconfined compressive strength after different cycles (0, 1, 3, 6, 9, 12) of freezing and thawing. Test results showed that with the increasing of weathered sand ratio, the unconfined compressive strength of expansive soil improved by weathered sand first increased and then decreased at the same cycles of freeze-thaw. When sand ratio was 10%, the unconfined compressive strength reached the maximum. With the increasing of freeze-thaw cycles, the unconfined compressive strength decreased in the presence of the same sand ratio, and the magnitude of the decrease also reduced with the increasing of freeze-thaw cycles. After regression analysis of test data, the mathematical model between unconfined compressive strength and freeze-thaw cycle was established. These two variables showed a natural logarithmic relationship, and this natural logarithm between unconfined compressive strength and freeze-thaw cycle displayed a linear negative correlation.