Experimental study of prestressed steel-HFRC composite girders under hogging moment

Abstract

To alleviate cracks in the hogging region of continuous steel-concrete composite girders, the hybrid fiber reinforced concrete (HFRC) and prestressing technique were introduced to exploit a novel type of composite girders (prestressed steel-HFRC composite girders). Four specimens with different concrete slabs (normal concrete (NC) slab, prestressed NC slab, HFRC slab, prestressed HFRC slab) were tested under hogging moment to investigate their mechanical properties. The test results showed that the prestressed steel-HFRC composite girder could take advantage of the synergy of the prestressing technique and HFRC and, therefore, its ultimate capacity, cracking load and stiffness were the biggest while the crack width was the smallest among the specimens investigated. In addition, practical equations of ultimate/crack moment and crack width were obtained based on the test results. The proposed equations could provide the reference in the design of prestressed continuous steel-HFRC composite girders.

Keywords

• Prestressing
• Hybrid fiber reinforced concrete
• Composite beam
• Test