Title: Permanent Participating FRP Formwork for Concrete Floor Slabs

Author(s): Xian Gai, Antony Darby, Tim Ibell and Mark Evernden

Publication: Symposium Paper

Volume: 275

Issue:

Appears on pages(s): 1-18

Keywords: Fiber reinforced polymer, GFRP dowels, moulded GFRP grating, putruded GFRP box sections, permanent participating formwork.

DOI: 10.14359/51682465

Date: 3/1/2011

Abstract:
This paper presents a new concept for an FRP-Concrete composite floor system. The system consists of a moulded glass fiber reinforced polymer (GFRP) grating adhesively bonded to rectangular pultruded GFRP box sections as structural formwork for a concrete slab. Holes cut into the top flange of the box sections at a variable spacing allow concrete ‘studs’ to form at the grating/box interface. During casting, GFRP dowels are inserted into the holes to further connect the grating and box sections. Following preliminary component tests on two concrete blocks, experimental results show that the concrete filled grating provides a 100% increase in strain capacity when compared to a plain concrete block. It is therefore feasible to provide ductility to the complete system through the concrete in compression. Four push-out GFRP grating-box section specimens were then tested in double shear to assess the shear behavior of the proposed GFRP dowel shear connector in both partially concrete-filled and fully concrete-filled box sections. From the resulting load-slip curves, a progressive longitudinal shear failure was seen to be provided by such a connection. The experimental results indicate that this type of shear connection can provide robustness and reasonable ductility to the system. Research is now underway to test a complete prototype system under variable load conditions to examine whether the behavior is as predicted.