以峰值轴向应变评价麦秸秆和石灰加筋固化盐渍土的抗变形性能

Evaluation on anti-deformation capability of saline soil reinforced by wheat straw and lime on the basis of axial strain at failure

为了解决滨海盐渍土的低强度和大变形问题,利用麦秸秆和石灰对盐渍土加筋及固化。完成了直径152mm重型击实试样、直径102mm轻型击实试样的无侧限抗压试验以及直径61.8mm试样的三轴压缩试验,分析了加筋土峰值轴向应变的变化规律,并在此基础上评价了加筋土的抗变形能力。结果显示随着含水率增加,加筋土的抗变形能力减弱;随着加筋长度和质量加筋率增加,加筋土的抗变形能力逐渐增强,超过一定的加筋长度和质量加筋率,加筋土的抗变形能力又开始减弱。加筋土的最优抗变形性能与麦秸秆的加筋条件有关。重型击实试样的适宜加筋长度为50mm,适宜质量加筋率为0.25%。轻型击实试样分别为30mm和0.25%。上部均匀加筋、整体均匀加筋和下部均匀加筋的直径为61.8mm的加筋石灰土试样则分别为20mm和0.25%。麦秸秆和石灰共同加筋固化可以使滨海盐渍土的强度和抗变形能力增强。

In order to increase the strength and anti-deformation capability of seaside saline soil,it can be reinforced by wheat straw or solidified by lime respectively or jointly.Unconfined compressive test for heavy compaction samples of 152 mm in diameter and lightly compaction samples of 102 mm in diameter,as well as triaxial shear test for samples of 61.8 mm in diameter have been carried out in succession of axial strain at failure of reinforced saline soil and reinforced lime-saline soil be calculated for analyzing its anti-deformation capability.The results indicated that anti-deformation capability of reinforced soil gradually weakens with the increase of water content of soil,but enhances gradually with the increase of reinforced length and reinforced ratio of wheat straw,and then decreasing after surpassing certain reinforced length and certain reinforced ratio.The optimal anti-deformation capability of the reinforced saline soil depends upon the reinforcement conditions by wheat straw.The suitable length is 50 mm for the heavy compaction sample,its suitable reinforced ratio is 0.25%.For the lightly compaction sample,they are 30 mm and 0.25% respectively.For the reinforced by lime soil sample of 61.8 mm in diameter with uniform reinforcement in the upper part,entirely,and in the lower part,they are 20 mm and 0.25% respectively.The joint reinforcement by wheat straw and line enhances the strength and anti-deformation capability of the seaside saline soil.