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The implementation of the urban underground logistics system (ULS) can effectively mitigate the contradiction between the surging logistics demand and the increased negativity of urban logistics. The widespread implementation of ULS still suffers from a lack of research into its operation in the marketplace, although the research on ULS system technology and network design appears to be sufficient. A new supply chain for logistics service based on ULS (ULS-SSC) was proposed, as ULS embedded in the urban logistics system could lead to the evolution of the role of supply chain participants. This article analyzed the organizational structure and operation characteristics of ULS-SSC and designed a top-down ULS-SSC operation process model based on the designed functional structure and subsystems relationship using the hierarchical colored Petri net (HCPN). The simulation results show that the integrated information management platform based on ULS can integrate urban logistics service supply chain resources and operate effectively under the two main service modes designed. The high-time delay intermediate links can be upgraded by system optimization, and the links with initial pickup and terminal distribution can be improved through outsourcing and supply chain collaboration. The findings provide new insights into the feasibility of the operation of ULS in the market and help stimulate the implementation of ULS.

Rock masses can be regarded as a blocky rock system. After a disturbance load is applied, the anomalously low friction phenomenon may take place and cause geological disasters. A series of impact experiments on granite blocks were conducted to investigate the anomalously low friction phenomena. Vertical vibration, Fourier frequency spectrum, and horizontal motions were investigated. It can be found that the tensile phases of vertical vibration can reduce the maximum static friction force, namely, the shear strength. The quasi-resonance operating mode of the rock blocks was observed. During the stress wave propagation, the vibration in the loading direction tends to transfer from high frequency to low frequency and the modes of stress wave propagation do not depend on disturbance energies. The observed translational and rotational motions were due to the initial shear force, which is less than the friction force with no disturbance load. Stability of the blocky rock system is very sensitive to the initial stress state. In the subcritical state, friction force reduction can easily break the equilibrium of forces along the contact surface and even a slight disturbance may make the horizontal motions happen, which may lead to geological disasters with great energy release.