# Deep Embedment (DE) FRP Shear Strengthening of Concrete Bridge Slabs under Loads Close to Supports
## 3 Experimental Programme  
### Details of Test Slabs  
The experimental test specimens were created to investigate the behaviour of one-way slabs representative of the typical sections of full scale bridge deck slabs. According to previous tests of one-way shear behaviour of concrete deck slabs by the authors [15], the test slabs were 2400 mm long \(\times\) 400 mm width \(\times\) 200 mm depth, as illustrated in Figures 2 and 3. A summary of the experimental details is presented in Table 1 and Figure 2. It is shown that the experimental programme involves eight test slabs. As presented in Table 1, the name of the test specimen includes all of its structural variables. For example, for the test specimen S-C-2-9, C is the strengthening material of CFRP (Carbon Fiber Reinforced Polymer), 2 is the strengthening configuration of two rows of embedment bars (see Figure 2c), and 9 is the diameter of embedment bars. Therefore, the variables to be investigated in this test are as follows:  
* Influence of strengthening materials, including steel, BFRP (Basalt Fiber Reinforced Polymer), GFRP (Glass Fiber Reinforced Polymer), and CFRP (test specimens labelled as S-S-2-10, S-B-2-9, S-G-2-9, and S-C-2-9);
* Influence of quantity of strengthening embedment bars (test specimens labelled as S-C-2-9 and S-C-1-9). The strengthening configuration is shown in Figure 2c,d;
* Influence of diameter of embedment bars (test specimens labelled as S-C-2-9 and S-C-1-13). Figure 3: Details of test specimens in cross section. \begin{table} \begin{tabular}{c c c c c c c c c} \hline \hline \multirow{2}{*}{**Model**} & \multicolumn{2}{c}{**Reinforcement**} & \multirow{2}{*}{**fcu (MPa) \({}^{*}\)**} & \multicolumn{2}{c}{**Embedment**} & \multicolumn{2}{c}{**Embedment**} & \multicolumn{2}{c}{**Diameter of**} & \multirow{2}{*}{**Failure Load**} & \multirow{2}{*}{**Failure Mode \({}^{**}\)**} & \multirow{2}{*}{**Medium**} \\  & \multicolumn{2}{c}{**Percentage (\%)**} & & & & & & & \\ \hline S-Con & 1.1 & 24.5 & N/A & N/A & N/A & 130 & SF & 8.67 \\ S-D-1 & 1.1 & 27 & N/A & N/A & \(-\)/16 & 134 & SF & 8.34 \\ S-S-2-10 & 1.1 & 24.5 & Steel & 2 \(\times\) 2 & 10/16 & 142 & BF & 22.54 \\ S-B-2 & 1.1 & 25.1 & BFRF & 2 \(\times\) 2 & 9/16 & 144 & BF & 17.61 \\ S-G-2.9 & 1.1 & 25.6 & CFRP & 2 \(\times\) 2 & 9/16 & 140 & BF & 19.36 \\ S-C-2-9 & 1.1 & 25.3 & CFRP & 2 \(\times\) 2 & 9/16 & 142 & BF & 17.4 \\ S-C-1-9 & 1.1 & 25.4 & CFRP & 2 \(\times\) 1 & 9/16 & 142 & BF + SF & 18.7 \\ S-C-1-13 & 1.1 & 25.8 & CFRP & 2 \(\times\) 1 & 13/20 & 148 & BF & 20.58 \\ \hline \hline \end{tabular}   
* *In addition, the control specimen, not strengthened with embedded bars, is labelled as S-Con. An unstrengthened test slab with drilling holes coded as S-D-1 is adopted to investigate the structural damage degree from the drilling-hole process. The test slabs were constructed by using normal-weight ready mixed concrete. The concrete average compressive strength (_fcu_) of the test slabs was evaluated at 28 days by carrying out direct compression tests on cube specimens of 100 mm \(\times\) 100 mm \(\times\) 100 mm. We obtained _fcu_ values between 24.1 MPa to 26.1 MPa at 28 days. For the internal reinforcement of the slab strips, high bond steel bars of 16 and 18 mm diameter were used. The configuration of internal reinforcement in the test slabs is shown in Figures 4 and 5. The yielding stress and tensile strength were obtained by means of uniaxial tensile tests. We obtained an average of 438 MPa and 458 MPa, respectively. The test method for the embedded steel bars was the same as the internal reinforcement. The test method for the embedment FRP bars was carried out according to the requirement of ACI 440-R06 [16] with the loading rate of 0.2 N/s. The test results of embedment strengthening bars are shown in Table 2. To bond the ETS steel bars to the concrete substrate, an FY-Z epoxy based adhesive was used. The tensile behaviour and elastic modulus of this adhesive were obtained by carrying out direct tensile tests.