In the study of the seepage characteristics of layered rock slope under rainfall conditions, the majority of previous research has considered the hydraulic conduction to be isotropic, or only considered the anisotropy ratio of the hydraulic conductivity, ignoring the anisotropy angle. In the current study, a layered rock slope in the Pulang region was selected as an example. Then, based on the fitting parameters of the Van Genuchten model, pore water pressure sensitivity analyses of the layered rock slope were carried out. The anisotropy ratio and anisotropy angle were used to analyze the sensitivity of the seepage and stability of the layered rock slopes. The results show that as the anisotropy angle of hydraulic conductivity of layered rock slope decreased, the maximum volume water content of surface (MWCS) of layered rock slope gradually increased. Additionally, as the anisotropy ratio decreased and the anisotropy angle increased, the rising heights of the groundwater (RHG) of layered rock slope gradually increased. When the hydraulic conduction of layered rock slope was considered isotropic, the factor of safety (FS) tended to be overestimated. As the anisotropy ratio decreased and the anisotropy angle increased, the factor of safety (FS) of layered rock slope decreased. Prevention should be the objective for rock slopes with larger dip angles in the bedding plane in the Pulang region. This study provides feasible schemes for the evaluation of the seepage and stability of layered rock slopes in Pulang region of southwestern China.

Compared with extrusion foaming, semi-solid-state batch foaming with CO 2 can produce foams with small bubble size and high expansion ratio using the polymers with regular melt strength as the raw material. However, due to the presence of crystal regions, semi-solid-state batch foaming of polypropylene (PP) is a challenge. In situ melting and rheological behaviors of PP were measured using high-pressure differential scanning calorimetry and high-pressure rheometer, respectively. Through the CO 2 pressure swing saturation strategy, the PP matrix can dissolve more CO 2 in a shorter time, thereby effectively widening the foaming temperature range, increasing the expansion ratio, and shortening the saturation time. The Gotsis' model was used to correlate the high-pressure rheological data to obtain the characteristic relaxation time and rigid modulus of PP, and then, the bubble growth stability during the foaming process was simulated. According to the Considere criterion, unstable growth factors were introduced to judge the quality of the foaming results. It was found that when the unstable growth factor was higher than 0.3, the bubbles began to collapse and rupture.

Shallow buried tunnels are commonly seen in engineering practice. To understand the failure mechanism of shallow buried tunnel is of significance in engineering practice. There is a reasonable judging index lacking in tunnel stability. The strength reduction method (SRM) gain limiting status of geotechnical materials by reducing the computation parameters. Then the failure zone can be obtained and showed. Finally, a safety factor can be obtained by this progress. This method has been used in slope stability analysis. The usage of this method is a new field. Based on shallow tunnel computation model under different cover depth, the SRM method is adopted in finding the safety factor of shallow buried tunnels. The displacement curve changing with the strength reduction factor is drawn and the catastrophe point is found as the safety factor. Further, by compared with the failure criteria of plastic zone connection and non-converge, also, compared with model tests, failure mechanism of shallow buried is analyzed. Specialty of these safety factors is discussed and it is proved that they maintain a accordance. This research is of significance for tunnels safety factors' study.

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