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Sulfuric acid corrosion is a non-negligible problem affecting the durability of concrete materials. To explore the mechanism of sulfuric acid corrosion on the fracture performance and microstructure of concrete, three-point bending test was utilized to analyze the evolutionary characteristics of the crack mouth opening displacement and the fracture toughness of concrete corroded by sulfuric acid. Scanning electron microscope and energy-dispersive spectrometer were utilized to analyze the characteristics of microscopic morphology and corrosion products of concrete corroded by sulfuric acid. The result shows that the fracture evolution of concrete can be divided into four stages: nonlinear development stage, linear development stage, deceleration expansion stage, and accelerated expansion stage. In purified water environment, the peak fracture load and fracture toughness of concrete is positively related to corrosion time. In sulfuric acid corrosion environment, the peak fracture load and fracture toughness of concrete are negatively related to corrosion time and concentrations of sulfuric acid solution. Microscopic experiments show that the interior of concrete is less affected by sulfuric acid corrosion, and the structure is relatively dense compared with the surface. The expansion crystal ettringite formed at the fracture surface of the concrete specimen during sulfuric acid corrosion was the main reason for the durability reduction of concrete. [ABSTRACT FROM AUTHOR]

Continuous and stepwise deformation of landslides occur widely during seasonal rainfall and reservoir operation. Therefore, it is important to develop resilient stabilizing structures to ensure that they continue to function even when large deformations occur. In this study, a new anchor cable with a high support and large shear deformation is proposed. The anchor cable primarily consists of free, grouting, and adaptive sections, which are connected using hinge connections. The adaptive section consists of an anchor with multiple trapezoidal gears, sleeve tube, connecting rod, and bearing balls. The adaptive section provides periodic working resistance to absorb and release energy and adapts to large deformations by continuously cutting gears with bearing balls. The working principle of the adaptive section was theoretically and experimentally analyzed. Its shear performance was compared to that of an ordinary cable under cyclic shear tests. The results indicated that: the ordinary cables broke after the first shear test; however, the new anchor cables still had high support after four shear tests (cumulative displacement: 0.8 m). Compared with ordinary cables, the new anchor cables experienced lower shear force, and provided higher working resistance with large shear displacement, because of the more uniform stress of the new anchor cable; energy was released in time under the action of the hinge connections and adaptive section. • A novel resilient cable with high working resistance and large shear deformation was proposed. • Adaptive section provides periodic resistance by continuously plastic flow. • The resilient behavior of the new cable is theoretically and experimentally analyzed. • New cable can bear larger shear displacement and uniform stress than ordinary cable. [ABSTRACT FROM AUTHOR]