Longitudinal shear in composite deck slabs using corrugated steel sheets

Profile deck steel sheets are used in composite deck slabs. These sheets are standard in dimensions and shapes besides they are supplied with embossments and indentations. Such sheets are not available in Iraqi markets nowadays therefore people used another type of sheets which are corrugated without embossments or indentations in very wide range. This study covers the use of such sheets in composite slabs as decks instead of standard profiled steel sheets. The study comprises testing slabs of dimensions 0.9 × 2.5 m reinforced by steel fabric mesh and rested on corrugated sheets. Two types of shear spans are selected shorter and longer to study the longitudinal shear force transmitted due to the applied loads according to the Eurocode 4. The shorter shear spans are 600, 500 and 400 mm while longer one is 800, 750 and 700 mm. The study extended to support the requirements of design equation of the Eurocode by shear bond method also known as m–k method. The evaluated values of m and k are 0.094 and 65 respectively. The result of k which plays a very important role in shear transfer is small compared to what available in literature, therefore it is recommended to make use of shear connectors in such construction or any else method.

The Effect of Adding Shear Connectors to the Composite Slabs with Different Geometry of Profile Steel Sheet

The aim of this research is to investigate experimentally the effect of adding shear connectors to the composite deck slabs which have various geometries of steel sheeting. The behavior and resistance of composite slab is basically depending on the development of longitudinal shear resistance. In this study six specimens of composite deck slabs which have different types of geometries of steel sheets (trapezoidal, triangle and T-shapes) with dimensions (1850mm x 500mm x 110mm) were casted and tested under four-point load in presence and absence of shear connectors in order to evaluate the behavior and longitudinal shear resistance of composite slabs. The results show that the adding shear connectors to composite slabs with trapezoidal shape and triangle shape act to increase ultimate load capacity by 22.2% and 17.8% respectively as compared with composite slabs without shear connectors while effect of adding shear connectors to the composite slab with T-shape was very little or can be neglected. As well as the adding shear connectors to composite slabs with trapezoidal shape and triangle shape act to decreasing the deflection as compared with the same load also act to enhance the general performance of slabs

Development of sustainable concrete bridge deck slab systems using corrosion-resistant GRFP bars

This research investigates the use of glass fiber reinforced polymer (GFRP) bars to reinforce the bridge deck slabs as well as jointed precast bridge deck slab in prefabricated bulb-tee pre-tensioned bridge girders. The experimental program included two phases. In phase (I), six precast slab joint details between flanges of precast bulb-tee girders were developed incorporating GFRP bars with straight ends, L-shaped ends and headed ends, embedded in a closure strip filled with non-shrink cement grout or ultra-high-performance concrete (UHPC). A total of 11 actual-size specimens representing the one-way slab system with the proposed joint details, in addition to 5 cast-in-place control specimens, were built and tested to failure to examine the structural adequacy of the proposed joint details. Based on the results from Phase (I), the best joint was selected for further tests in Phase (II) to examine its fatigue life and ultimate load carrying capacity under vehicular wheel loading. A total of 8 actual-size, GFRP-reinforced, 3500 X 2500 X 200 mm concrete deck slabs were designed for this purpose according to CHBDC specifications. Ultimate strength, fatigue behavior and fatigue life of the GFRP-reinforced deck slabs were investigated using different schemes of fatigue loading, namely: accelerated variable amplitude fatigue loading and constant amplitude fatigue loading. Overall, the experimental results indicated that GFRP-reinforced deck slabs showed high fatigue performance. A new prediction model for fatigue life of the GRFP-reinforced deck slabs was developed. The failure mode of the tested composite slabs was punching shear. Correlation between the experimental findings and the prediction models for punching shear resistance available in the literature showed that the prediction models by CSA S806-12 (2012) and El-Gamal et al. (2005) can accurately predict the punching shear capacity of the cast-in-place and precast jointed bridge deck slabs reinforced with GFRP bars. In addition, the average observed mid-depth punching shear perimeter for the cast-in-place deck slabs and the precast jointed deck slabs were measured to be 1.25 d and 1.33d away from the sides of the loaded area, respectively, which are more than twice the corresponding distance specified in ACI 440.1R-06 and CSA S806-12 for calculating the critical punching shear perimeter.

Development of sustainable concrete bridge deck slab systems using corrosion-resistant GRFP bars

This research investigates the use of glass fiber reinforced polymer (GFRP) bars to reinforce the bridge deck slabs as well as jointed precast bridge deck slab in prefabricated bulb-tee pre-tensioned bridge girders. The experimental program included two phases. In phase (I), six precast slab joint details between flanges of precast bulb-tee girders were developed incorporating GFRP bars with straight ends, L-shaped ends and headed ends, embedded in a closure strip filled with non-shrink cement grout or ultra-high-performance concrete (UHPC). A total of 11 actual-size specimens representing the one-way slab system with the proposed joint details, in addition to 5 cast-in-place control specimens, were built and tested to failure to examine the structural adequacy of the proposed joint details. Based on the results from Phase (I), the best joint was selected for further tests in Phase (II) to examine its fatigue life and ultimate load carrying capacity under vehicular wheel loading. A total of 8 actual-size, GFRP-reinforced, 3500 X 2500 X 200 mm concrete deck slabs were designed for this purpose according to CHBDC specifications. Ultimate strength, fatigue behavior and fatigue life of the GFRP-reinforced deck slabs were investigated using different schemes of fatigue loading, namely: accelerated variable amplitude fatigue loading and constant amplitude fatigue loading. Overall, the experimental results indicated that GFRP-reinforced deck slabs showed high fatigue performance. A new prediction model for fatigue life of the GRFP-reinforced deck slabs was developed. The failure mode of the tested composite slabs was punching shear. Correlation between the experimental findings and the prediction models for punching shear resistance available in the literature showed that the prediction models by CSA S806-12 (2012) and El-Gamal et al. (2005) can accurately predict the punching shear capacity of the cast-in-place and precast jointed bridge deck slabs reinforced with GFRP bars. In addition, the average observed mid-depth punching shear perimeter for the cast-in-place deck slabs and the precast jointed deck slabs were measured to be 1.25 d and 1.33d away from the sides of the loaded area, respectively, which are more than twice the corresponding distance specified in ACI 440.1R-06 and CSA S806-12 for calculating the critical punching shear perimeter.

Development of Empirical Equations and Tables For the Design of Bridge Cantilever Deck Slabs Under CHBDC Truck Loading

This study recommends new simplified equations for the transverse moment and shear force at the base of the cantilever overhang due to applied vertical truck loading. This was made possible through a parametric study that utilized finite-element modelling on bridge deck cantilevers with variable lengths and slab thicknesses. Different end stiffening arrangements were considered that are encountered in practice, and included but were not limited to the PL-1, PL-2 and PL-3 New Jersey-type barriers walls, a PL-2 parapet, and a curb supporting intermittent steel posts carrying a guardrail. The barrier length changed from 3 to 12 m and the cantilever length ranged from 1.0 to 3.75 m. Further to the empirical expressions that had been developed, the study is supported by tables that were developed to readily design the cantilever slab, based on vertical loads due to vertical truck loading, as well as horizontal railing loads against the barrier wall.

Development of Empirical Equations and Tables For the Design of Bridge Cantilever Deck Slabs Under CHBDC Truck Loading

This study recommends new simplified equations for the transverse moment and shear force at the base of the cantilever overhang due to applied vertical truck loading. This was made possible through a parametric study that utilized finite-element modelling on bridge deck cantilevers with variable lengths and slab thicknesses. Different end stiffening arrangements were considered that are encountered in practice, and included but were not limited to the PL-1, PL-2 and PL-3 New Jersey-type barriers walls, a PL-2 parapet, and a curb supporting intermittent steel posts carrying a guardrail. The barrier length changed from 3 to 12 m and the cantilever length ranged from 1.0 to 3.75 m. Further to the empirical expressions that had been developed, the study is supported by tables that were developed to readily design the cantilever slab, based on vertical loads due to vertical truck loading, as well as horizontal railing loads against the barrier wall.