Study on Longitudinal Deformation Profile of Rock Mass in a Subsea Tunnel

During tunnel excavation, the deformation of surrounding rock due to the unloading of rock mass will vary with time. However, the measured displacement of surrounding rock is only a part of the actual longitudinal deformation profile. There is a need to analyze the longitudinal deformation profile to identify the deformation state and evaluate the stability of surrounding rock mass. In the present article, the variation of pre-deformation of surrounding rock due to excavation was analyzed, and the release coefficient was obtained from the measured results. For the Qingdao subsea tunnel, the measured crown settlement of surrounding rock was analyzed using the regression analysis method, and the longitudinal deformation profile of rock mass was simulated using the numerical calculation method. Moreover, based on the conditions of the subsea tunnel, a solid-fluid coupling model test was carried out to check the reliability of the numerical calculation results. The results of the model test were consistent with the numerical calculation results.     

Effects of pre-deformation on the martensitic transformation and magnetocaloric property in Ni-Mn-Co-Sn ribbons

This paper investigates the martensitic transformation and magnetocaloric effect in pre-deformed Ni-Mn-Co-Sn ribbons. The experimental results show that the reverse martensitic transformation temperature T_M increases with the increasing pre-pressure, suggesting that pre-deformation is another effective way to adjust T_M in ferromagnetic shape memory alloys. Large magnetic entropy changes and refrigerant capacities are obtained in these ribbons as well. It also discusses the origin of the enhanced martensitic transformation temperature and magnetocaloric property in pre-deformed Ni-Mn-Co-Sn ribbons.