This study tests the physical and mechanical properties of fresh bamboo to explore its suitability for reinforcing the embankment of a highway. A series of experiments is performed using a bamboo species (Sinocalamus affinis) and soil specimens with bamboo grids that are similar to geogrids. The testing indexes include the natural density, water content, wall thickness, and the outer perimeter of bamboo culm. The mechanical property tests include a uniaxial compression test on bamboo culm, tensile and flexural tests on bamboo strips, a friction test on the bamboo–soil interface, a pullout test on a single bamboo strip in a soil specimen, and a triaxial compression test on a soil specimen with a bamboo grid. The results show that the density and water content of fresh bamboo become relatively stable after growing for 2 years and the bamboo strips can satisfy the specification requirement for a traditional geogrid because of their excellent mechanical properties. Based on the physical and mechanical test results, appropriate cutting age of fresh bamboo is 2 years and more. In addition, the compressive strength for bamboo grid–reinforced soil is significantly greater than that of prime soil, and could effectively prevent filling embankments from settling. In addition, its increased shear resistance could suppress a slip shear failure in the filling embankment.

Rock fractures always influence the hydrological properties of a rock mass. To investigate the seepage characteristics of a rock mass with partly filled fractures, a mathematical model is established. In this model, the clear fluid in fractures is governed by the Navier-Stokes equation, and the fluid both in the porous medium and rock matrix are subjected to the Brinkman-Extended Darcy equation. The analytic solution of an equivalent permeability coefficient for a rock mass with partly filled fractures is solved, and it could be reduced to some special known results. Comparisons with experimental data show good agreement, thus verifying the validity of the present computations.

The linearisation of the Hoek–Brown failure criterion is a commonly encountered problem in rock mechanics. The fact that the minor principal stress used for estimating the equivalent Mohr–Coulomb parameters is the stress at failure cannot be ignored. This article proposes a method for estimating the most likely position of any arbitrary stress point that corresponds to the minimum shear strength on the Hoek–Brown curve. The interval of the minor principal stress at failure, which is employed in the existing equivalent estimation methods, is determined from the actual stress level of the rock mass. The Hoek–Brown failure envelope is divided into several zones, which enables its actual stress gradient variation to better match its curvature. The proposed method is applied to analysis of a slope example. The results show that, as the actual Hoek–Brown strength curve of each material is more finely divided, both the safety factor of the slope and the location of the slip surface based on the equivalent Mohr–Coulomb model agree more closely with those obtained from the Hoek–Brown model.