Study on a quantitative method for determining mixing proportion of transparent cemented soil for visual geotechnical model tests

An effective mixing of transparent cemented soil is necessary for visual
geotechnical model tests, so a quantitative method for determining mixing
proportion of transparent cemented soil was generated in this paper.
Firstly, quartz sand, Nanoscale silica powder and N-dodecane mixed 15#
white oil were selected as the raw materials, and a series of orthogonal
experiments were designed. Concurrently, the main physical and mechanical
parameters (volumetric weight γ, internal friction angle φ, cohesion c) of
transparent cemented soil were measured, caused by the change of
"particle size of quartz sand" and " mass ratios between
fumed silica and fused quartz". Subsequently, multiple linear
regression equations of various physical and mechanical parameters (γ, φ,
c) were obtained by fitting the original test data. Finally, the
rationality of multiple linear regression equations was proved. The
research results indicated: (1) the volumetric weight changes from
16.13kN/m3 to 12.53kN/m3, the Internal friction angle is between 27.07°
and 14.82°, and the cohesion varies from 31kPa to 2.3kPa, the parameters
meet the similar requirements of the surrounding rock (grade ⅳ and ⅴ) and
clay; (2) The values of Multiple R values (all greater than 0.88) and the
Significance F value (all close to 0) proves the three regression
equations were valid; (3) Combining the three regression equations and
particle size of quartz sand, the mass ratio between fumed silica and
fused quartz and geometry similarity constant were solved. All the
conclusions mentioned could provide theoretical support and data reference
for transparent soil model test implementation.