**Appendix A**

The cement was made of local brand of 52.5 grade OPC, and Ganjiang river medium sand was used for fine aggregate with a fineness modulus of 2.8; well-graded basalt was used for coarse aggregate with a maximum particle size less than 16mm. The main chemical composition for bonding properties of the constituent materials are shown in Table A1. The average fineness of the slag powder, density, water reduction rate, activity index on 28d, and activity index on 56d were 3 microns, 2.40 g/cm<sup>3</sup> , 10–15%, 105–110% on 28d, and 110–125%, respectively.

**Table A1.** Chemical constituents of Diatomite, SiO<sup>2</sup> and mineral powder (%).


Silicon Powder was made by local Building Materials Co., Ltd. according to GB/T176-1996 [55]. The test results of Silicon powder measured by GB/T18736/2002 [56] is reported in Table A2.


**Table A2.** Silicon powder performance index.

Steel fibers: Straight copper-plated steel fibers with a diameter of 0.2 mm, length of 13 mm, tensile strength of 2000 MPa, and volume fraction of 1.5% were used as steel fibers. Figure A1 shows the steel fibers mixed with C80 high-performance concrete. Table A3 shows the physical properties of the steel fibers utilized in the experimental test.


**Figure A1.** Steel fiber in concrete. **Figure A1.** Steel fiber in concrete.

Water reducer: Superplasticizer of a local chemical company was used. The index parameters are listed in Table A4. Water reducer: Superplasticizer of a local chemical company was used. The index parameters are listed in Table A4.


**Table A4.** Performance index of water reducer.

Index 2 0.02 21±1 ≤ 0.2 ≤ 3.0 40 ≥<sup>25</sup> Water: Ordinary tap water was used in the experiment.

**Cement Slag** 

**powder** 

coarse aggregate = 1.83, steel fiber = 0.15, water = 0.27, and water reducer = 0.018.

**Concrete** 

**Water binde r ratio**  **Sand rate**  (**%**)

Test result 6.5 1.046 21.5 0.05 0.12 23 30.4 C60 concrete and C80 concrete were tested, and each concrete was designed with three mixing ratios. Three sets of test pieces were made for each combination, and each group had three cube test pieces. After conducting the strength test, the design mix ratio was optimized. The concrete mix of C60 and C80 is shown in Table A5.

Water: Ordinary tap water was used in the experiment. C60 concrete and C80 concrete were tested, and each concrete was designed with three mixing ratios. Three sets of test pieces were made for each combination, and each group had three cube test pieces. After conducting the strength test, the design mix ratio was optimized. The concrete mix of C60 and C80 is shown in Table A5. **Table A5.** Benchmark mixture proportion of C60 and C80 high-performance concrete. **The amount of raw material used per concrete**  When the C60 high-performance concrete bridge deck of the test beam was prefabricated, eight groups of 150 mm cubic test blocks and two groups of 150 × 150 × 300 mm prism test blocks were made. Four groups of cube blocks with the same curing conditions of the bridge deck were tested. For two groups of cubes, compressive strength was measured when the cumulative temperature reached 600 ◦C. One group was tested for cube compressive strength on the test day, and the other was preserved. The remaining four groups were them used for standardization; among them, two groups were used for measuring 7-day compressive strength, one group was used for measuring 28-day compressive strength of concrete cube, and one group was used for testing splitting strength. The prismatic test block is standard for testing the 28-day axial compressive strength of concrete and elastic modulus. Three groups of 150 mm cubic test blocks and two groups of 150 × 150 × 300 mm prismatic test blocks were made when C80 steel fiber high-performance concrete was poured into the reserved holes. Two

C80\*\* 0.25 38 435 87 652 1063 157 10.44 58 87 \*Cement = 0.75, slag powder = 0.25, fine aggregate = 1.35, coarse aggregate = 2.03, water = 0.3, Admixture = 0.012. \*\*Cement = 0.75, slag powder = 0.15, Silica powder = 0.1, fine aggregate = 1.124,

When the C60 high-performance concrete bridge deck of the test beam was prefabricated, eight groups of 150 mm cubic test blocks and two groups of 150 × 150 × 300 mm prism test blocks were made. Four groups of cube blocks with the same curing conditions of the bridge deck were tested. For two groups of cubes, compressive strength was measured when the cumulative temperature reached 600 °C. One group was tested for cube compressive strength on the test day, and the other was preserved. The remaining four groups were them used for standardization; among them, two groups were used for measuring 7-day compressive strength, one group was used for measuring 28 day compressive strength of concrete cube, and one group was used for testing splitting strength.

**Fine aggregate**  **Coarse** 

**aggregate Water Water** 

**reducer** 

**Silica fume** 

**Steel fiber**  groups of cubic specimens were used to obtain the 28-day cubic strength and splitting strength of C80 steel fiber high-performance concrete and the remaining one group was preserved. At the same time, two groups of prism specimens were used to test the 28-day axial compressive strength and elastic modulus of concrete. Both cube and prism specimens were loaded by universal testing machine. The test results and elastic modulus of C60 high-performance concrete cube under standard curing and actual curing condition (i.e., the same curing condition with bridge deck) are shown in Tables A6–A8. The test results of C80 steel fiber high-performance concrete cube and elastic modulus are shown in Tables A9 and A10.


\* Cement = 0.75, slag powder = 0.25, fine aggregate = 1.35, coarse aggregate = 2.03, water = 0.3, Admixture = 0.012. \*\* Cement = 0.75, slag powder = 0.15, Silica powder = 0.1, fine aggregate = 1.124, coarse aggregate = 1.83, steel fiber = 0.15, water = 0.27, and water reducer = 0.018.

**Table A6.** Concrete strength obtained from the experimental test on standard C60 HPC cubic specimen.


**Table A7.** Concrete strength obtained from experimental test on C60 HPC cubic specimen at the same condition with bridge deck.


\* Strength measured at the same curing condition with bridge deck.



**Table A9.** Concrete strength obtained from the experimental test on standard C80 HPC cubic specimen.



**Table A10.** Elastic modulus and Poisson's ratio obtained from the experimental test on C80 HPC.
