复合材料改性城市路基土短龄期三轴力学特性

摘要:

为了探究纳米MgO对水泥路基土短龄期下的改性效果,分别对水泥改性路基土(简称“水泥土”)和1.5%掺量纳米MgO改性水泥路基土(简称“纳米水泥土”)试样进行不固结不排水(UU)三轴试验。结果表明：(1)水泥土和纳米水泥土试样的偏应力—轴向应变曲线均为软化型曲线,试样表现为脆性破坏。(2)水泥土和纳米水泥土试样力学特性的提升均对围压的升高具有较好的敏感性。(3)纳米MgO的掺入对水泥土试样的峰值应力、残余应力、黏聚力和内摩擦角均具有较好的提升效果。上述结果表明,掺入纳米MgO对水泥土试样进行力学特性改善是可行的,并且纳米MgO主要在于试样结构的改善。

Abstract:

In order to explore the effect of Nano-MgO on the modification of cement subgrade soil under short age, non-consolidation and non-drainage (UU) triaxial tests were carried out respectively on the samples of cement modified subgrade soil (referred to as "cement-soil Nano-MgO modified cement subgrade soil (referred to as "Nano-cement-soil The results show that: (1) the deviation-axial strain curves of cement-soil and Nano-cement-soil samples are softening curves, and the samples show brittle failure. (2) The improvement of mechanical properties of cement-soil and Nano-cement-soil have good sensitivity to the increase of confining pressure. (3) The addition of Nano-MgO has a good improving effect on the peak stress, residual stress, cohesion and internal friction Angle of cement soil samples.The above results show that it is feasible to improve the mechanical properties of cement soil samples by adding Nano-MgO, and Nano-MgO mainly focuses on the improvement of the sample structure.