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This study evaluates the impact of compaction on the soil–water characteristic curve of unsaturated remodeled weakly expansive soils by assessing changes in soil pore structure resulting from variations in compaction. The remodeled weakly expansive soil in the Xinjiang Hami area is taken as the research subject to investigate how compaction affects microscopic pore structure using mercury intrusion testing. Subsequently, mercury intrusion porosimetry is employed to examine pore structure and distribution patterns at different dry densities. Based on the capillary principle and experimental methods (filter paper method and pressure plate method test), modified soil–water characteristic curves are obtained by fitting them with a three-parameter model law. The results indicate that higher dry density leads to an increased air intake value and significantly reduces the total volume of large pores within samples. Both the Fredlund and Xing model and the three-parameter model effectively capture the influence of initial dry density on the development pattern of the soil–water characteristic curve. [ABSTRACT FROM AUTHOR]

Abstract: An aluminum doped titanium silicon carbide with a composition of Ti3Si0.9Al0.1C2 was studied by neutron powder diffraction in comparison with the standard Ti3SiC2 and Ti3AlC2 compounds. The refinements of the diffraction data revealed the included impurity phases and the detailed structural information of these compounds. The analysis confirmed that the impurity phase TiC in Ti3SiC2 could be eliminated by the substitution of Si with a small amount of Al dopant, forming a solid solution of Ti3(Si1−x Al x )C2, with a unit cell slightly larger than that of Ti3SiC2, but smaller than that of Ti3AlC2. However, compared with the anisotropic structure change in Ti3AlC2, the structure change in Ti3Si0.9Al0.1C2 is basically isotropic, which is consistent with the structural optimization of the first principles calculation. [Copyright &y& Elsevier]