The floor heave is one of soft rock roadway distortion. Based on soft rock supporting theory and engineering practice, the program bolt-mesh-anchors and floor corner, bolts coupling support to control floor heave of the soft rock roadway is proposed. Numerical simulation results show that bolt-anchors can mobilize the strength of the deep adjacent rock, at the same time, and properly arranged floor corner bolts with high bending rigidity can cut the slip-line field and achieve the goal of controlling floor heave effectively.
The yttria-stabilized zirconia (YSZ) is a famous thermal barrier coating material to protect hot-end components of the engine. As a characteristic feature of the YSZ, the surface roughness shall play an important role in the interface thermal conductance between the YSZ and gas, considering that the gas is typically at an extremely high temperature. We investigate the effect of the surface roughness on the thermal conductance of the YSZ-gas interface with surface roughness described by nanoscale pores on the surface of the YSZ. We reveal two competitive mechanisms related to the microstructure of the pore, i.e., the actual contact area effect and the confinement effect. The increase of the pore depth will enlarge the actual contact area between the YSZ and gas, leading to the enhancement of the solid-gas interface thermal conductance. In contrast to the positive actual contact area effect, the geometry-induced confinement effect greatly reduces the interface thermal conductance. These findings shall offer some fundamental understandings for the microscopic mechanisms of the YSZ-gas interface thermal conductance.
Because of crossing point’s large span, stress concentration clearly, result in parts of the intersection of poor support, construction and maintenance difficult, especially Y-Intersection is more serious part of deformation and failure. Through situ investigation and theoretical research, summarize the typical failure modes of the deep large Y-intersection, analyze the main reasons for destruction of the crossing point that is both sides of Bovine unconstrained and supported respectively. The new coupling supporting design—bolt-mesh-cable + truss to control the top of crossing point , while the key technology of the double control bolt is used to control the Crossing point.—is proposed.
High temperature tensile tests of novel developed Nb-microalloyed weathering steels were carried out with a constant true strain rate of 0.001/s at 650°C-1300°C using Gleeble3500 thermo-mechanical simulator. The tensile strength (TS) and reduction in area (RA) were calculated afterwards to obtain hot ductility curve and hot strength curve of the steel. The hot ductility behaviors were studied in detail under optical microscope (OM), scanning electron microscope (SEM) and transition electron microscope (TEM). The third brittle zone of the studied steels was between 650°C-800°C. SEM fractographs and microstructures of the tensile specimen showed that the occurrence of the third brittle zone was mainly related to the formation of pro-eutectoid ferrite film along the prior austenite grain boundaries, and secondly to the precipitation of second phases. Therefore, it was recommended that the straightening temperature of the studied steel after casting should be kept over 800°C to get crack free continuous casting (CC) slabs.
scite is a Brooklyn-based organization that helps researchers better discover and understand research articles through Smart Citations–citations that display the context of the citation and describe whether the article provides supporting or contrasting evidence. scite is used by students and researchers from around the world and is funded in part by the National Science Foundation and the National Institute on Drug Abuse of the National Institutes of Health.
hi@scite.ai
10624 S. Eastern Ave., Ste. A-614
Henderson, NV 89052, USA
Copyright © 2024 scite LLC. All rights reserved.
Made with 💙 for researchers
Part of the Research Solutions Family.