**6. Conclusions**

In this paper, the interface bond mechanism between the CFRP grid–PCM reinforcing layer and concrete was investigated via pull-out tests, and a numerical simulation method based on the simplified mechanical model was proposed. The main conclusions can be drawn as follows:

(1) The tensile strength utilization ratio of the CFRP grid in specimen C6D50 was 81% higher than in specimen C6D100, and the tensile strength utilization ratio of the CFRP grid in specimen C8D50 was 23% higher than in specimen C8D100. Meanwhile, the maximum load of specimen C8D50 with the CR8@50-type CFRP grid was nearly 2.5 times higher than that of specimen C6D50 with the CR6@50-type CFRP grid, and the maximum load of specimen C8D100 with the CR8@100-type CFRP grid was 3.5 times higher than that of specimen C6D100 with the CR6@100-type CFRP grid. The use of a CFRP grid with a larger cross-sectional area and smaller grid interval

can significantly improve the interfacial bearing capacity between the CFRP grid– PCM reinforcing layer and the concrete. Moreover, the interfacial bond behavior between the reinforcing layer and the concrete can be effectively enhanced by using an interfacial binding agent;


**Author Contributions:** H.D. modeled the structure and wrote the paper; B.W. designed the study; J.Z. (Jiawei Zhang) contributed to the revision; J.Z. (Junlei Zhang) contributed to the fabrication of specimens and acquisition of data; K.U. designed the experimental program. All authors have read and agreed to the published version of the manuscript.

**Funding:** The authors gratefully acknowledge the Shaanxi Province Youth Science and Technology Rising Star Foundation (Grant No. 2021KJXX-17), the China Postdoctoral Science Foundation (Grant No. 2017M610616), and the Fundamental Research Funds for the Central Universities (Grant No. 300102280202) for supporting this research.

**Institutional Review Board Statement:** Not applicable.

**Informed Consent Statement:** Not applicable.

**Data Availability Statement:** Data available on request due to restrictions eg privacy or ethical. The data presented in this study are available on request from the corresponding author. The data are not publicly available due to the restriction of follow-up research.

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