Carbide slag has been used to prepare solidified soil to effectively reduce the stacking and disposal of carbide slag and achieve efficient resource utilization. Because of the significant brittleness and low strength of carbide-slag-stabilized soil, fibers were added to carbide-slag-stabilized soil in this experimental study. The effects of fiber length and fiber content on the unconfined compressive and indirect tensile strengths of carbide-slag-stabilized soil were investigated. The concepts of the density of fibers in solidified soil and the number of fibers in a unit volume solidified soil were proposed, and the effects of fiber distribution density on the mechanical properties of the solidified soil were evaluated. The fibers increased the indirect tensile strength of the carbide-slag-solidified soil, which was significantly higher than the unconfined compressive strength of the solidified soil. The fibers had no significant effect on the unconfined compressive and indirect tensile strengths of the 7 d carbide-slag-solidified soil but increased those of the 28 d carbide-slag-solidified soil. The enhancement effect was the most significant when a 0.3% content of 19 mm long fibers was incorporated into the carbide-slag-solidified soil.

In order to analyze the tension stress of Geomembrane in the seepage control system of a landfill in a heavy metal contaminated area under the action of the overlying landfill weight, the internal force of Geomembrane in a landfill is studied in this paper. Firstly, according to the internal force analysis of Geomembrane model, the basic equation of Geomembrane is obtained, and the equation is analyzed by finite difference numerical solution, so as to analyze the internal force of Geomembrane in a landfill. The method can analyze three stress states of Geomembrane-clay interface at different positions: elastic state, softening state and residual state, which makes the stress analysis of Geomembrane on landfill slope more reasonable. Parametric analysis shows that when the strength loss and the difference between residual displacement and peak displacement are small in the softening stage, the peak strength of Geomembrane-clay interface has little influence on the maximum tensile stress of Geomembrane and its residual strength is the main controlling factor, and when the softening characteristics of Geomembrane-clay interface are obvious, the influence of peak strength and residual displacement is more obvious. ABSTRACT Study on the Internal Force of Geomembrane of Landfill in Heavy Metal Contaminated AreaEstudio sobre la fuerza interna de la geomembrana del relleno sanitario en un área contaminada con metales pesados Con el fin de analizar el esfuerzo de tensión de la Geomembrana (una lamina geosintética que busca evitar la migración de contaminantes al suelo) en el sistema de control de infiltración de vertederos en áreas contaminadas con metales pesados bajo la acción del peso del vertedero suprayacente, en este documento se estudia la fuerza interna de la Geomembrana en los vertederos. En primer lugar, de acuerdo con el análisis de fuerza interna del modelo de la Geomembrana se obtiene la ecuación básica de la lámina, y la ecuación se analiza por solución numérica de diferencia finita para medir su fuerza interna en el relleno sanitario. El método puede analizar tres estados de tensión de la interfaz de Geomembrana-arcilla en diferentes posiciones: estado elástico, estado de reblandecimiento y estado residual, lo que hace que el análisis de tensión de la Geomembrana en la pendiente del vertedero sea más razonable. El análisis paramétrico muestra que cuando la pérdida de resistencia y la diferencia entre el desplazamiento residual y el desplazamiento máximo son pequeñas en la etapa de reblandecimiento, la resistencia máxima de la interfaz Geomembrana-arcilla tiene poca influencia en el esfuerzo de tensión máximo de la Geomembrana, y su resistencia residual es el principal factor de control; y cuando las características de ablandamiento de la interfaz Geomembranaarcilla son obvias, la influencia de la resistencia máxima y el desplazamiento residual es más obvia. RESUMEN Record

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A large number of sinusoidal fractures exist in the open-pit slopes of mines, and the mechanical properties of shear failure are of great significance to the stability of the open-pit slope. Sandstone specimens containing sinusoidal fractures with different undulated heights were prefabricated by the CNC sand-wire-electrode cutting technology to explore the effect of sinusoidal fractures on the mechanical properties of shear failure of rock masses. The TFD-20H/50J rock shear testing machine was used for shear tests on sinusoidal-fracture sandstone with different undulated heights. In the shear loading process, the prefabricated-fracture sandstone specimens with different undulated heights have the fracture-compacting stage, linear-elastic changing stage, bottom-up stage, and residual strength stage. Before peak strength, the sinusoidal prefabricated-fracture rock masses with different undulated heights have the precursory characteristics of decreased stress, which can provide an early warning for the instability and failure of rock masses. The undulated height of sinusoidal fractures significantly affects the fracture initiation and propagation of specimens. Fractures occur and develop from the prefabricated fractures at low undulated height (≤10 mm) to multiple ways under the high undulated height (>10 mm); that is, fractures occur at the prefabricated fractures and the end of specimens simultaneously. With the increased undulated height, the fractures expand from parallel to the slope of the prefabricated fractures to perpendicular to the prefabricated fractures. The fracture propagation direction of sinusoidal-fracture rock masses with different undulated heights is mainly from the middle of the slope surface of prefabricated fractures to the end. It is the main direction of the shear failure of sinusoidal prefabricated fractures, and the monitoring of weak planes should be strengthened in the actual slope engineering.