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Tunnel face stability is significant to the safety in constructing soil tunnels. Based on the analysis of controlled deformation in rocks and soils (ADECO-RS), a quantitative method was developed to determine the required number of fiberglass anchors (FGA) for the soil tunnel utilizing both analytical and numerical methods. As an application example, the tailrace tunnel in the Israel K project employed 25 fiberglass anchors based on an analytical method to increase the safety factor of the tunnel face to 1.5, which is close to the result of the numerical method by FLAC3D. The effects of fiberglass anchor type and construction equipment on the required number of fiberglass anchors in the tunnel face were also analyzed. The results benefit the optimized support design of the tunnel face for similar tunnels in soil.

Observations of marble brittle failure at the laboratory scale indicates that the failure process involves the initiation, growth and accumulation of micro-cracks. With the micro-cracks increasing, marble subjected to long-term loading will be damaged. The rate of cracking is sensitive to the magnitude of long-term loading. The static-failure tests were conducted and the test results indicate that the time-dependent is being. Process simulation tests have been conducted to investigate the time-dependent failure in JPII marble. The static-failure data were used to match the parallel-bonded stress corrosion (PSC) model parameters which based on PFC2D (Particle Flow Code in 2 Dimension). The time-dependent failure was simulated. The response was characterized by a creep curve. The damage mechanisms and deformation behavior of marble were discussed. The model exhibits damage mechanisms and deformation behavior that are similar to those of the rock.