# Study on Bending Performance of Tightly Spliced Truss-Reinforced Plate-Honeycomb Flat Beam
## 5 Conclusions  
In this study, based on the experimental research on the bending capacity of the tightly spliced truss-reinforced plate-honeycomb flat beam, the effects of the size of the opening of the H-shaped steel beam, the spacing of the opening, and the height of the web are explored. The difference between the splicing of composite plates and cast-in-place was compared and studied. The validated numerical model was used for parametric analysis. The calculation formula for the bending capacity of this type of composite flat beam was proposed and the design method was suggested. The following conclusions were obtained:  
1. The failure of the specimen is mainly divided into two states: the deflection exceeds the limit, and the concrete flange plate is separated from the steel beam. The honeycomb holes can effectively connect the concrete flange plates on both sides of the steel beam web by passing through the steel bars and concrete inside and can better disperse the stress of the concrete in the middle of the span so that the stress distribution of the concrete flange plates is more uniform. The concrete flange plate in the honeycomb composite flat beam, including its steel bars, has a shear lag effect along the width direction after the specimen yields.
2. The process of the honeycomb composite flat beam under bending load is mainly divided into two parts: the elastic stage and the plastic deformation stage. When the bearing capacity reaches 0.75 times the ultimate bearing capacity, the structure exhibits significant damage and degradation. The pure bending section of the specimen forms a plastic hinge in the plastic stage, and the average ductility of the specimen reaches 8.2, which has good ductility.
3. The simplified method proposed in this article for calculating this type of honeycomb composite beam has an error of less than 10% in terms of bending bearing capacity, which has advantages over the DT method. The calculation method and design suggestions proposed in this study provide a basis for the research and application of this type of composite flat beam.  
**Author Contributions:** Conceptualization, X.M. and X.L.; methodology, X.M. and J.L.; formal analysis, X.M. and S.Z.; investigation, X.M. and H.L.; resources, X.M. and H.L.; data curation, J.L.; writing--original draft preparation, X.M. and S.Z.; writing--review and editing, H.L. and X.L.; visualization, X.M.; supervision, H.L.; funding acquisition, H.L. All authors have read and agreed to the published version of the manuscript.  
This research was funded by the National Key R&D Program (2018 YFD1100203) and Research Funds for Jiangsu Collaborative Innovation Centre for Building Energy Saving and Construction Technology (SJXTZD2102, SJXTBS2118).  
Not applicable.  
The data used to support this study are available from the corresponding author upon request.  
The experimental work described in this paper was conducted at the Jiangsu Key Laboratory of Environmental Impact and Structural Safety in Civil Engineering at the China University of Mining and Technology. The help received during the testing from staff and students at the laboratory is greatly acknowledged. All authors have read and agreed to the published version of the manuscript.  
The authors declare no conflict of interest.