An experimental investigation on longitudinal shear of composite slab based on eurocode 4

Abstract

There are generally four modes of failure for Composite Slabs – Longitudinal shear (shear bond) failure, Vertical shear failure, Flexural failure and Punching shear failure. Of the four modes, longitudinal failure is considered to be the governing criteria in the design of composite slabs as it yielded the lowest load that caused the composite slab to fail. In this project, verification of the longitudinal shear as the lowest failure load and distinct mode of failure in composite slab will be shown (in conjunction with project ST48AB). Interface between the concrete and the steel profiled sheet (metal decking) was studied with respect to BS EN 1994-1-1:2004 (Eurocode 4). Data analysis based on both Eurocode 4 and BS5950–4:1994 (BS5950) will be compared.

Full-scale experiment was carried out for 8 composite slab specimens – four of which were longer specimens (4x1x0.125m) and the remaining ones were shorter specimens (2.6x1x0.125m). Test setups were in accordance to Eurocode 4 due to the conciseness and systematic approach and data generated were analyzed by both standards from the Eurocode 4 and BS5950.

The design shear resistances (V1,Rd and Vut) from the full scale experiment were analyzed using Eurocode 4 and was found to be higher than BS5950 (Vs). This means that it is theoretically less conservative based on the Design shear resistance from Eurocode 4. Despite so, the design shear resistance obtained from m-k method (V1,Rd) is still below the actual shear (Vt) rendering it is safe to apply in design. However, when analysed using partial interaction method, it is found that the design shear resistance (Vut) is higher than both V1,Rd, Vs and Vt. Therefore, it is not recommended for use.

Keywords: Composite slab; longitudinal shear; shear resistance; m-k method; partial interaction method