Abstract:

In order to determine the ratio of similar materials commonly used in physical simulation experiments, four raw materials including river sand, barite powder, gypsum and cement were selected, and orthogonal design was adopted. Bone glue ratio (ratio of river sand mass and  barite powder mass to gypsum mass and cement mass), water-paste ratio (ratio of cement mass to gypsum mass) and barite content (ratio of barite powder mass to aggregate mass), with five levels for each factor, were set to carry out density test and acoustic emission test under uniaxial compression. The sensitivity of different proportions to the physical and mechanical indexes of similar materials and the indexes of damage degree were determined. The experimental results show that the density, compressive strength and elastic modulus of similar materials under the influence of bone glue ratio have the largest range, which are 0.13 g/cm3, 2.60 MPa and 247 MPa, respectively, F-test has the largest value, and the significance is the highest. Poisson’s ratio has the largest range under the influence of barite content, which is 0.09, and has the highest significance. The relative cumulative damage degree (D) had the largest range (0.25) under the influence of bone glue ratio, and the F test value was the most significant. In general, the bone glue ratio controls the density, compressive strength, elastic modulus and D of similar materials.

Key words: physical model test, similar material, orthogonal design, sensitivity, characteristics of injury