Currently, most research on prefabricated steel frame joints focuses on column-column or beam-column connections. However, there has been a lack of effective research on prefabricated column-beam-column joints with higher construction efficiency. In this paper, we present the construction and installation process and technical characteristics of a novel prefabricated column-beam-column joint (NPJ). Initially, we describe the technical specifications of the NPJ. Following this, we examine the mechanical performance of the NPJ using a validated finite element model and conduct a detailed analysis of various parameters affecting its performance. Subsequently, we propose a simplified method for calculating the performance of the NPJ, adhering to existing design codes. Our findings indicate that the NPJ exhibits robust mechanical properties, closely matching those of traditionally welded joints. Notably, the height of the beam emerges as a critical factor influencing the NPJ's load-bearing capacity, more so than the thickness of the lug. This research offers valuable insights and technical guidance for further exploration and practical application of prefabricated steel frame joints.

Current research on the effects of corrosion on the safety of steel members is primarily focused on the degradation of the ultimate bearing capacity, and there is a lack of research on the reliability-based service life assessment. In this paper, a modified reliability function and an uncertainty model for each parameter considering the effects of corrosion are established based on the reliability analysis method of the GB50068-2018 design specification. The effects of the corrosive environment category, wall thickness, and slenderness ratio on the time-varying reliability of axially compressed round tubes are analyzed. The results indicate that an increase in the corrosion duration and the environmental category can cause a decrease in the reliability index of the component, and the smaller the wall thickness, the faster the corrosion-related degradation of the reliability index. However, with the increase of the slenderness ratio, the corrosion-related degradation of the reliability index gradually decreases. In the end, a residual life prediction method and a design correction method for corroded components based on the reliability index are proposed. Moreover, the values of the corrosion life and corrosion coefficient of circular steel tubes for different environmental categories, slenderness ratios, and thicknesses are determined. This paper provides a technical reference for the residual life prediction and full life design of round steel tubes considering local corrosion.