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The application of fabricated segmental lining in deeply buried inclined shafts in complex strata has been significantly increased in recent years. However, the structural safety of the fabricated lining is vulnerable to high ground stress and high water pressure, as well as the vibration of mechanical equipment and ground disturbance caused by coal mining. Thus, applying an automatic load-monitoring system to the inclined shaft in coal mines has great engineering importance in evaluating structural safety. In this study, an automatic monitoring and data transmission system for the inclined shaft was developed. In addition, by considering the non-linear characteristics of segment joints and different working states of concrete segments, a more functional assessment method was proposed based on the limit state assessment theory. According to the in situ monitoring project in the number 2 inclined shaft of Bulianta coal mine in China, the calculated internal forces are in good agreement with the monitored data, and the proposed assessment method shows reliable results during the operation period. [ABSTRACT FROM AUTHOR]

Abstract: A structural-controlled synthesis of manganese oxide nanostructures from single Mn3O4 precursor via hydrothermal method is presented. The obtained products include α- and β-MnO2 nanorods, γ-MnO2 urchin-like microspheres, birnessite nanowires and nanosheets. The morphology evolution process and the effect of varying reaction parameter to the phase and morphology are systematically investigated. The formation mechanisms have been rationalized. The obtained nanostructures are as the model system for studying the electrochemical capacitance performances, which have been investigated by cyclic voltammetry. [Copyright &y& Elsevier]

• The influence mechanism of integral transverse passage on two parallel tunnels is studied. • A new-type assembled transverse passage is proposed in this paper. • The vibration attenuation effect of the assembled transverse passage is studied through experiments. Transverse passages are ubiquitous in urban subways, and they pose serious mutual threats to the two adjacent tunnels they connect. In this paper, the frequency sweep loads were applied in model tests and the influence mechanism of integral transverse passage (ITP) was studied by using the one-third octave of the frequency response function (FRF). Subsequently, a new assembled transverse passage (ATP) was proposed and its vibration attenuation effect was studied. The results showed that, when the frequency sweep load is applied to one tunnel, the adjacent tunnel is more susceptible to a load that has a central frequency of 12.5–80 Hz due to the existence of ITP. The closer the loading frequency is to 31.5 Hz, the greater the impact on the adjacent tunnel becomes. When an ATP is used, the vertical acceleration level (VAL) of the tunnel to which the load is applied will increase by 1.3 dB, while that of the adjacent tunnel will decrease by 7.2 dB, and the transverse passage will decrease by 8.7 dB. Compared to the ITP, when the lining structure of an adjacent tunnel is closer to the ATP, the reduction in the vibration response of the structure is more pronounced, and the vibration response is reduced over a larger central frequency range. [ABSTRACT FROM AUTHOR]