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Laboratory tests have been conducted to investigate the effects of thermal damage on diorite under microwave irradiation. The sample rocks were heated to high temperature range of 300 to 800 ? in a single-mode microwave furnace. The experimental results show that the rocks started to crack at 500 ? and completely disintegrated at 700 ?. The intensities of quartz diffraction peaks were almost unchanged while the diffraction peak intensity of hornblende gradually decreased with temperature increasing. In addition, the chlorite diffraction peak disappeared at 500 ?. The compressive strength of the sample decreased to 40% at 600 ? and it approached zero at 700 ?. In this paper, the possible reasons for the thermal effects on the fracture of diorite were discussed, which can be related to water evaporation, thermal cracks and mismatch thermal expansion, and phase transition on quartz. The result indicates that diorite can be effectively destroyed under microwave irradiation

The WMI (weak muddy intercalation) is a typical weak structural surface in the red-bedded rock mass; ensuring slope stability by increasing the strength of the WMIs helps reduce project costs and carbon emissions. With the advantages of energy saving, high efficiency, and green, microwave technology has attracted scholars' attention to geotechnical material property improvement. However, the mineral composition of the WMIs is complex and variable, and the applicability of microwave technology needs further evaluation. In this paper, the effects of microwave temperature and clay mineral types and content on the physical and mechanical properties of the WMIs were evaluated. The results show that microwave heating can substantially improve the uniaxial compressive strength of the WMIs, regardless of the types and content of clay minerals. Dehydration, dehydroxylation of clay minerals, and local melting of albite occurring in the specimens under microwave heating enhanced the strength of the soil particles and the interparticle joints. The strength increase ratios of the WMI specimens increased with the temperature increase. With the increase in clay mineral content, the strength increase ratio of kaolinite WMIs and illite WMIs decreased, while the strength increase ratios of montmorillonite WMIs increased. The present multiple regression analysis methods are used to establish the strength prediction models of the WMI microwave-reinforced specimens, which can guide the engineering application. [ABSTRACT FROM AUTHOR]

The bearing stratum of high-rise and ultra-high-rise buildings in southwest China has inevitably faced moderately weathered red mudstone. It was a waste of the potential bearing stratum calculated according to the specification, as the bearing stratum obtained from laboratory and in situ tests was much higher than the values suggested by the specification. Rock mass surface deformation detection is of great significance in the safety management of a foundation project. Some correlation between surface deformation and failure characteristics may exist that could help to understand the bearing stratum of the moderately weathered red mudstone. This research was conducted to study the progressive failure characteristics of the moderately weathered red mudstone through surface deformation. In situ load, triaxial, and binocular visual technology were employed for data acquisition. The proposed conjecture was illustrated and verified by a group of experiments from three construction sites. Five stages could be described as the progressive failure of the moderately weathered red mudstone: compaction, elasticity, elastoplasticity, plasticity, and failure. Furthermore, the surface displacement increment fluctuates with the loading time and fades into the distance. Therefore, this research could provide a robust, practical application for analyzing the progressive failure of moderately weathered red mudstone. [ABSTRACT FROM AUTHOR]

It is shown that a weighted Hilbert inequality for double series can be established by introducing a proper weight function. Thus, a quite sharp result of the classical Hilbert inequality for double series is obtained. And a similar result for the Hilbert integral inequality is also proved. Some applications are considered.

It is shown that some new extensions of Hilbert's integral inequality with parameter λ(λ>1/2) can be established by introducing a proper weight function. In particular, when λ=1, a refinement of Hilbert's integral inequality is obtained. As applications, some new extensions of Widder's inequality and Hardy-Littlewood's inequality are given.