Unbonded Steel Strand for Pre-stressed Concrete

I. Product Introduction 1. Definition and Structure Unbonded Steel Strand is a special steel strand used in prestressed concrete structures. Its core feature is that the steel strand is not directly bonded to the concrete. The specific structure is as follows:   Core Steel Strand: Usually made of 7 high-strength steel wires, made of high-carbon steel, with a tensile strength grade of 1860MPa, with high strength and low relaxation performance. Wrapping layer: The outer layer of the steel strand is wrapped with a layer of high-density polyethylene (HDPE) sheath, and the sheath is filled with anti-corrosion lubricating grease to form a completely isolated "unbonded" state. 2. Key Features Unbonded performance: The sheath is separated from the concrete, and the steel strand can slide relative to the concrete when subjected to force, avoiding the stress transfer failure problem caused by concrete cracking in traditional bonded steel strands. Anti-corrosion ability: HDPE sheath and grease l…