# Tension Performance of Precast Bridge Deck Longitudinal Joints with Different Configurations
## 2 Materials and Methods  
Six test specimens were fabricated with the joint width, rebar type, and steel plate as the parameters, as presented in Table 1, to evaluate the effects of each parameter on the joint behavior under tension loads. Specimens J100-HB-SP and J150-HB-SP were compared to evaluate the effects of joint width, and specimen J100-NB-SP was evaluated to determine the effects of the presence of rebars. Specimens J0-LB-NP and J0-LB-SP were evaluated to determine the effects of looped rebars and were compared to determine the effects of the presence of steel plates. Finally, C-SB-NP was evaluated to provide a comparison with typical CIP construction. Figure 1 depicts a side and top view of J100-HB-SP, which represents a precast bridge deck joint with a hooked rebar, steel plate, and width of 100 mm. All rebars had an elastic modulus of 200,000 MPa and yield stress of 400 MPa, which met the SD400 specification, and had a diameter (d) of 32 mm, corresponding to the required anchorage development or lap splice length of 15 d = 480 mm. The compressive strength of the deck slab concrete was 43 MPa with an elastic modulus of 30,000 MPa. Figure 2 shows the specific configuration of each test specimen defined in Table 1. \begin{table}
\begin{tabular}{c c c c} \hline
**Test Unit Name** & **Joint Width** & **Rebar Type** & **Steel Plate** \\ \hline J100-HB-SP & 100 mm (J100) & Hooked rebar (HB) & Steel plate (SP) \\ J150-HB-SP & 150 mm (J150) & Hooked rebar (HB) & Steel plate (SP) \\ J100-NB-SP & 100 mm (J100) & No rebar (NB) & Steel plate (SP) \\ J0-LB-NP & NA (J0) * & Looped rebar (LB) & No plate (NP) \\ J0-LB-SP & NA (J0) * & Looped rebar (LB) & Steel plate (SP) \\ C-SB-NP & Cast-in-place (C) & Straight rebar (SB) & No plate (NP) \\ \hline \end{tabular}  
* The joint widths for the looped rebar specimens are as shown in Figure 2; these values are not applicable (NA) to the joint width comparison, given the differences between the hooked and looped rebar configurations and are indicated by the specimen nomenclature.  
\end{table} 
Table 1: Test parameters. Figure 1: Dimensions of the J100-HB-SP precast bridge deck longitudinal joint. **(a)** Side view. **(b)** Top view. Figure 3 shows the test specimen fabrication process. First, the formwork was constructed by fabricating the rebar (Figure 3a). Each rebar cage was first assembled and placed inside the fabricated formwork (Figure 3b). Next, the concrete for the slabs that represented  
Figure 2: Details of precast bridge deck longitudinal joint specimens. (**a**) J150-HB-SP. (**b**) J100-NB-SP. (**c**) J0-LB-NP. (**d**) J0-LB-SP. (**e**) C-SB-NP. the deck units was poured and cured for 28 d (Figure 3c). Finally, non-shrink concrete was cast in the joint section and cured for an additional 28 d before testing (Figure 3d). Figure 4 shows the test setup of this study. A longitudinal load was applied using an actuator to induce tension throughout the joint in each specimen. The capacity of the actuator was set to 200 t. The relative displacement of the joint under a tension load was measured using a displacement transducer connected to the data logger (Figure 4a). The attachment of bridge decks to actuators requires high-strength bolts with a minimum diameter of 24 mm, but the use of bolts to attach concrete specimens to rigid frames and actuators would not provide sufficient bearing strength. Hence, 32 mm diameter reinforcement was used for these joints. To secure the concrete specimens to the test frame and prevent deformation, five 250 mm spaced rebars were arranged in two rows, 200 mm and 700 mm from each specimen end. These bars were inserted into the ducts that were preinjected into the sample. The actuator joints were attached by arranging three rebars 180 mm apart in one row, 300 mm and 320 mm from the other end of each specimen. The bar was embedded in a 50 mm hole drilled in each test sample prior to the test (Figure 4b).