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A corrugated grouted sleeve (CGS) made of a seamless tube, which is easy to produce at low cost, is presented. To investigate the connection behavior of CGS splices, a total of 33 specimens are manufactured and tested under monotonic loads. The effects of the corrugation number, groove depth, and steel bar diameter on the connection performance of the CGS are examined. The test results show that the proposed CGS is deemed an effective and reliable steel bar connector for precast structure buildings due to the groove in the corrugation, which plays a key role as a wedge to prevent bond failure of the steel bar splice and enhance the confinement action of the sleeve; one corrugation formed by the roll extrusion method at the end of the seamless tube is sufficient to provide a wedge action to ensure steel bar failure first; the depth of the groove is suggested to be more than 2 mm to ensure that the bond strength is sufficient before steel bar fracture. Finally, an analytical model is proposed to predict the tensile resistance of the CGS considering the influence of confinement caused by the corrugations, and the predictions are in good agreement with the experimental data.

The physical and mechanical parameters and degradation mechanisms of red sandstone in the Mount Wuyi scenic area were studied under the action of dry–wet cycles. Dry–wet cycle, acoustic wave velocity, water saturation rate, and triaxial compression tests were conducted, aided by scanning electron microscopy and X-ray diffraction testing techniques. The study’s results show that the dry–wet cycle effect on red sandstone is a major factor in the degradation of its physical and mechanical parameters and that its microstructural characteristics are significantly affected. The P-wave velocity, peak strength, elastic modulus, internal friction angle, and cohesion decreased, the water content and peak strain increased, and the elastic modulus was the most sensitive to dry–wet cycles. A dry–wet cycle’s action severely damages the microstructural integrity of the red sandstone. After 15 dry–wet cycles, the interstitial fillings between the skeletal grains are dissolved over a large area, microfractures are interwoven throughout, and the structure is severely fragmented. The microstructural degradation of the red sandstone by dry–wet cycles mainly manifests in the dissolution of the interstitial filler, and the relative content of calcite as an interstitial filler is reduced by 46.6% after 15 dry–wet cycles. The proposed strength decay prediction equation has reference significance for the strength prediction of the red sand conglomerate in the project. This study’s results can provide theoretical support for the landscape protection of rock masses and the prevention of engineering geological hazards.