Search

The precision and reliability of test findings are closely related to the uniformity of remolded loess samples. Although many methods to evaluate the uniformity of remolded loess have been proposed, they have not been widely accepted, due to the many defects. Therefore, it is necessary to explore the evaluation method and index of the uniformity of remolded loess samples in laboratory tests. In this paper, variations in shear strength and microscopic properties along the sample height were examined using the direct shear test and scanning electron microscopy (SEM) test. The feasibility and reliability of employing shear strength as an indicator to assess the uniformity of remolded loess samples were confirmed based on the test results. The results showed that the shear strength and shear strength parameters decreased from top to bottom along the sample height, and that the difference in the shear strength and shear strength parameters between the top and the bottom of remolded loess samples increased with the increase in the sample height. The variation tendency of the shear strength and shear strength parameters altered when the height–diameter (H/D) ratio exceeded 0.97. The SEM test results revealed that as the sample height increased, the disparity in microstructure and pore distribution in various portions of remolded loess samples became more apparent. The effect of sample height on the uniformity of remolded loess samples was mostly attributable to the variation in coating thickness and the content of clay particles on the surface of coarse particles, induced by a reduction in compactness from the top to the bottom of samples. The coefficient for evaluating the uniformity of the remolded loess sample was defined as the ratio of the shear strength at the top to that at the bottom of the remolded sample, and 0.8 was chosen as the threshold value. The shear strength reflected the uniformity of remolded loess samples as accurately as the microscopic test parameters. Furthermore, the direct shear test is the most classic and widely used laboratory test, with a low cost, easy accessibility, short test cycle, simple data processing and low environmental requirements, which provides another feasible method to evaluate the uniformity of remolded loess.

Aluminium Hybrid Composites are the new group of metal matrix composites (MMCs) due to their attractive properties like high ductility, high conductivity, light weight and high strength to weight ratio and is a response to the dynamic ever-increasing demand of these super material in the field of aircrafts and marines. Carbon Nanotube (CNTs) are also known for their high strength and stiffness and their low density which when combined together makes CNTs an ideal reinforcement. This work briefly reviews the research revelation of an Aluminium (Al-6061) based hybrid metal matrix composite reinforced with CNTs and TiO2. The Hybrid Aluminium Metal Matrix Composites (AMMCs) is prepared with various CNTs weight percentages (0, 0.5, 1 and 1.5 wt. %) and keeping TiO2 weight percentage fixed to 1%.Stir Casting (SC) is focused in general to successfully fabricate the MMCs. The discussion of this work revolves around tensile test, hardness test, and Scanning Electron Microscope (SEM) of the MMC. The mechanical properties of the fabricated MMCs materials like tensile strength, hardness and impact strength is found by using these experimental methods. It has been observed that the tensile strength of the MMCs increases in the presence of TiO2 and CNTs and increases even more with the increase in the weight fraction of CNTs. Same results have been obtained for hardness and impact strength where there is an increase in them in the presence of TiO2 and CNT and their value increases even further with increase in weight fraction of CNTs