**5. Conclusions**

In this study, nine push-out specimens were designed to study the bond behavior and the bond slip between section steel and RAC, and four factor e ffects of the concrete strength were investigated. Numerical analysis was conducted, and the simulation and test data were analyzed. The results are summarized as follows:


**Author Contributions:** Writing—review and editing, C.L., L.X. and H.L.; Resources, Z.Q., G.F., J.W., Z.L. and C.Z. All authors have read and agree to the published version of the manuscript.

**Funding:** This research was funded by [the National Natural Science Foundation of China] gran<sup>t</sup> number [51878546], [the Innovative Talent Promotion Plan of Shaanxi Province] gran<sup>t</sup> number [2018KJXX-056], [the Key Research and Development Program of Shaanxi Province] gran<sup>t</sup> number [2018ZDCXL-SF-03-03-02], [the Key Laboratory Project of Shaanxi Province] gran<sup>t</sup> number [XJKFJJ201904], [the Science and Technology Innovation Base of Shaanxi Province "Technology Innovation Service Platform for Solid Waste Resources and Energy Saving Wall Materials"] gran<sup>t</sup> number [2017KTPT-19].

**Acknowledgments:** The authors would like to acknowledge the National Natural Science Foundation of China (Grant No. 51878546), the Innovative Talent Promotion Plan of Shaanxi Province (Grant No. 2018KJXX-056), the Key Research and Development Program of Shaanxi Province (Grant No. 2018ZDCXL-SF-03-03-02), the Key Laboratory Project of Shaanxi Province (Grant No. XJKFJJ201904), and the Science and Technology Innovation Base of Shaanxi Province "Technology Innovation Service Platform for Solid Waste Resources and Energy Saving Wall Materials" (2017KTPT-19) for financial support.

**Conflicts of Interest:** The authors declare no conflict of interest.
