Experimental research on interfacial bonding performance of high‐strength steel pipe and surrounding concrete/grout for assembled composite columns

Abstract

High‐strength steel pipe joints are proposed for assembled composite columns. The steel pipe extends into the upper and lower prefabricated columns and is anchored by poured concrete or grout to realize the connection of the prefabricated columns. Bonding performance of high‐strength steel pipe and surrounding concrete/grout is critical to the joint reliability. Steel pipe push‐out test was carried out, considering parameters of steel pipe section specification, bonding length, bonding material, and outer wall treatment of the steel pipe. Comparative analysis of measured load–displacement/slip curves and calculated bond strength were conducted. Bonding length of 600 mm could provide sufficient bond strength. Increasing bonding length could delay the slippage, but the bond strength decreased. High‐strength grout significantly increased the peak load size. The slenderness ratio and diameter–thickness ratio of the steel pipe had no obvious influence on the bonding performance. Steel pipe with D114*25 section obtained higher bonding strength with smaller ratio of bonding area to cross‐sectional area. Spiral ribs welded to the outer wall of the steel pipe could effectively improve the bonding strength and delay the interface slip. With easy construction and reliable performance, spiral ribs were recommended to be applied in prRactical projects.

Utilizations of Steel-Reinforced Concrete-Filled Steel Tubular (SRCFST) Constructions

“…This effect substantially elevates the ultimate compressive strain and ultimate compressive strength of the concrete. In comparison to conventional carbon steel, steel-reinforced concrete boasts several advantages, including simplified structural configurations, convenient construction, reduced section dimensions, exceptional ductility, high load-bearing capacity, and the ability to effectively address a wide array of modern building requirements [4][5][6][7] .…”