Characterisation of nano magnesia–cement-reinforced seashore soft soil by direct-shear test
Characterisation of nano magnesia–cement-reinforced seashore soft soil by direct-shear test
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DOI：
10.1080/1064119x.2018.1515283
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发表时间：
2019-01
影响因子：
2.2
通讯作者：
Wei Wang-;Chen Zhang;Na Li;Feifei Tao;Kai Yao
中科院分区：
文献类型：
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作者：
Wei Wang-;Chen Zhang;Na Li;Feifei Tao;Kai Yao
摘要通过对海滨软土（3S）、水泥加固海滨软土（C3S）和纳米镁水泥加固海滨软土（NmC3S）的直剪试验，对纳米镁水泥加固海滨软土（NmC3S）的力学性能进行了评价和表征。对比结果表明，NmC3S比C3S和3S具有更大的抗剪强度和变形模量。在剪切位移达到1.0 mm之前，C3S和NmC3S的剪应力均显著增加，在达到临界状态之前，剪应力急剧下降。破坏位移随施加法向应力的增大而增大。NmC3S的摩擦角大于C3S和3S；但其衔接程度介于C3S和3S之间。此外，提出了描述剪切应力-位移曲线的数学模型，可以有效地模拟这三种黏土的应变硬化和应变软化曲线。最后，提出了一个用于捕获这三种材料的应力-位移行为的广义公式，并解释了每个参数的物理含义。
Abstract In this study, the mechanical behaviour of nano magnesia–cement-reinforced seashore soft soil (NmC3S) was evaluated and characterised by the direct-shear testing of seashore soft soil (3S), cement reinforced seashore soft soil (C3S) and NmC3S. The comparison among these three types of soils indicates that NmC3S has greater shear strength and deformation modulus than C3S and 3S. The shear stress of both C3S and NmC3S increase significantly prior to a shear displacement of 1.0 mm, followed by a sharp decline before reaching the critical state. The failure displacement increases as the applied normal stress increases. NmC3S demonstrated greater friction angle than both C3S and 3S; however, the magnitude of its cohesion lies between that of C3S and 3S. Moreover, a mathematical model that describes the shear stress–displacement curve was proposed, which can effectively model the strain-hardening and strain-softening curves of these three types of clays. Finally, a generalised formula for capturing the stress–displacement behaviour of these three materials is presented with the explanations for the physical meaning of each parameter.