08.30: Experimental investigation and specific behaviour of X‐HVB shear connectors in prefabricated composite decks

Abstract

Construction industry is constantly facing new demands towards fast construction and smallest possibly quantity of work at the construction site. These increasing demands, in the field of composite construction of buildings and bridges, resulted in development of different types of prefabricated composite decks during decades and group arrangement of different types of shear connectors. Positioning of shear connectors into envisaged openings of prefabricated composite decks contributes to smaller quantity of concrete needed to infill openings of prefabricated composite decks. Composite action between steel profile and concrete decks can be achieved using X-HVB shear connectors with powder-actuated fasteners. Anchorage mechanisms developed between steel profile and fasteners during installation process of powder-actuated fasteners are resulting in composite action between steel and concrete. Relatively simple and fast installation process, without requirements for additional equipment and electrical power on the site is characteristic for this type of shear connectors. Experimental investigation of X-HVB shear connectors in prefabricated composite decks through standard push-out tests, according to EN 1994-1-1 is presented in this paper. Shear connectors are positioned at the envisaged openings of prefabricated composite decks at the minimal longitudinal and transversal distances, recommended by the manufacturer. Two different orientations of shear connectors, forward and backwards to shear force direction are experimentally investigated and presented in this paper. Experimentally obtained characteristic shear resistance are compared with recommendations given by manufacturer. Characteristic slip at failure obtained from experimental investigation is compared with requirements given in EN 1994-1-1 in order to determine if this type of shear connector is considered as ductile. Eight specimens in two series are experimentally investigated through standard push-out test. Different characteristic shear resistance and different failure modes are obtained for forward and backward orientation of shear connectors. Experimentally obtained results from standard push-out tests for different orientations of shear connectors are compared with results obtained from extensive numerical analysis performed in Abaqus.

The performance of composite beams with X-HVB shear connectors after being subjected to fire exposure

“…The shear connecter (X-HVB) is an L-shaped shear connector that comes in various heights (from 40 to 140 mm). Hilti DX 76 or DX 76 PTR powder-actuated tools and Hilti DX cartridge equipment were used to attach two XENP-21 HVB nails to the composite constructions with or without profiled steel sheeting [13]; Fig. 2 depicts all of these components.…”

“…(a) X-HVB shear connector with two X-ENP-21 HVB nails [15] (b) DX 76 PTR tool, equipped for X-HVB installation [16] (c) cartridges [16] Fig. 2: Hilti X-HVB System.…”

Experimental investigation of influence parameters on cartridge fired pin resistance

“…Pull-out, coming together with tilting of fasteners, is also characteristic of shear connectors fastened to the steel base material with the same cartridge fired pins and placed in solid or composite concrete slabs [4,5,12]. The average shear force per one fastener, when they are applied for utilization of shear connection with X-HVB shear connectors in solid concrete slabs, is between 17.79 kN and 20.96 kN.…”

“…The average shear force per one fastener, when they are applied for utilization of shear connection with X-HVB shear connectors in solid concrete slabs, is between 17.79 kN and 20.96 kN. The shear force range is captured for various specimen layouts [5,12] and energy driven through fastening. The lower value of shear force is achieved for specimens where fasteners were installed with the settlement of 2.0 power level on the power regulation device, while higher force is obtained for 3.5 power level, which is the same value used for installation of shear test specimens -ST.…”

Review of Various Shear Connectors in Composite Structures

“…X-HVB shear connectors prevent vertical uplift forces by using the X-HVB head and nails and are designed to resist desired shear forces with suitable ductility (Hilti X-HVB System [94]). Gluhović et al [95] tested the prefabricated composite deck by conducting push-out tests pursuant to Eurocode 4 [10] to assess the shear capacity of X-HVB connectors with powder-actuated fastener X-ENP-21 HVB nails. Their results showed that 26% higher slip to failure and 16% higher ultimate shear resistance to forward orientated shear connectors.…”