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In the process of excavation of hydraulic tunnels across the fault zone, the surrounding rock often lose steady and collapse, which will threaten the personal security. In this paper, a 3D model was established according to Hami pumped storage power station in Xinjiang. The variation of surrounding rock stress, deformation and plastic zone under the condition of full section excavation without support and timely support after excavation are compares and analysis. The calculated results indicate that the initial ground stress decreases along the axis of the tunnel in fault zone. In the case of excavation without support, the stress of surrounding rock in the fault zone will be released completely. The maximum deformation of tunnel vault along the axis is located in the left affected zone. In the case of timely support after excavation, the stress of surrounding rock in the fault zone will be partially retained. The deformation of tunnel vault is much smaller than that without support after excavation and the upper part of tunnel in fault zone basically has no plastic failure.

The exploitation of bio-based foams implies an increase in the use of renewable biological resources to reduce the rapid consumption of petroleum-derived resources. Both tannins and furfuryl alcohol are derived from forestry resources and are therefore considered as attractive precursors for the preparation of tannin-furanic foams. In addition, toughening modification of tannin-furanic foams using polyvinyl alcohol (PVOH) resulted in a more flexible network-like structure, which imparts excellent flexibility to the foams with acquirement of relative properties that are even close to those of polyurethane foams, which are the most used polymers for fabrication of insoles for athletes. In addition, the addition of PVOH did not affect the thermal insulation of the foams, resilience and elongation at break, while reducing the brittleness of the samples and improving the mechanical properties. Also the observation of the morphology of the foam indicated that the compatibility between PVOH and tannin-furanic resin is good, and the cured foam does not show fragmentation or collapse, while the bubble pore structure is uniform. The developed flexible foam derived from biomass resources endowed the foam good thermal insulation properties and high mechanical properties, and the samples exhibited suitable physical parameters to be used as flexible insoles for athletes.