Flexural Performance of Prestressed Composite Recycled Aggregate Slabs with Steel Tube Trusses

• Published in: KSCE journal of civil engineering 2022, 26(12), , pp.5253-5263
• Main Authors: Liu, Enming, Lin, Mingqiang, Xie, Qun, Zhang, Yue
• Format: Article
• Language: English
• Subjects: Aggregates; Bearing capacity; Bottom casting; Cast in place; Civil Engineering; Compression; Compression zone; Concrete; Concrete aggregates; Concrete slabs; Cracking (corrosion); Engineering; Failure; Geotechnical Engineering & Applied Earth Sciences; Industrial Pollution Prevention; Mechanical properties; Precast concrete; Prestressing steels; Reinforced concrete; Reinforcing steels; Slabs; Steel; Steel tubes; Steel wire; Strain; Structural Engineering; Trusses; Ultimate loads; Wire ropes; 토목공학
• ISSN: 1226-7988; 1976-3808
• DOI: 10.1007/s12205-022-0563-x

A new type of prestressed composite recycled aggregate floor slab was developed and its flexural performance was studied. The composite floor comprises a top cast-in-place slab made of recycled coarse aggregate concrete and a bottom precast concrete slab with grouted steel tube trusses. The cracking load, ultimate load, deflection, steel tube strain, concrete strain and failure process are studied for different contents of recycled coarse aggregates. Results show that the mechanical performance of the prestressed composite recycled aggregate slab has two distinctive stages. And the load bearing capacity decreases with the increase in the amount of recycled coarse aggregates. When the composite slab fails, the prestressed steel wires in the tension zone yield and concrete in the compression zone is crushed. This failure characteristic reflects that the reinforcement ratio of the component is appropriate. The cracking moment and ultimate moment calculation formulas of the composite slab are established and could predict the cracking and failure points. In the formulas, the influence of the amount of recycled coarse aggregates on the flexural capacity is considered. By controlling the content of recycled aggregates, the composite slabs with steel tube trusses can be sued in practical applications.